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Grading the forecasts for Irene; Katia organizing; threat of a Gulf of Mexico storm

By: Dr. Jeff Masters, 4:38 PM GMT on August 31, 2011

Recovery from the destruction left behind by Hurricane Irene continues in the mid-Atlantic and New England states today. Irene's storm surge, winds, and record rains likely did $3 - $6 billion in insured damage to the U.S., according to AIR-Worldwide. Since actual damages are typically double insured losses, Irene's total price tag will likely be $6 - $12 billion, making it one of the top 20 most expensive hurricanes to hit the U.S. Irene will be one of the most expensive Category 1 hurricanes ever; the record is held by 1972's Hurricane Agnes, which did $11.8 billion in damage (2010 dollars.) As AIR Worldwide notes in their press release, part of this damage is due to the costs of evacuation for the 2 million people that were evacuated. It costs approximately $1 million to evacuate each mile of U.S. coast warned (Aberson et al., 2006). This number will be higher for more densely populated areas of the coast, such as Miami, and may be a factor of six lower for the North Carolina coast (Whitehead, 2003). So were we over-warned during Irene? Could the costs of the storm been lower due to better forecasts and fewer evacuations?


Figure 1. The National Hurricane Center forecast for Hurricane Irene issued five days before it hit Long Island, NY, compared with the actual track of Irene. The landfall locations along the coasts of North Carolina, New Jersey, and New York were pretty much spot-on, though the time of arrival was off by a few hours. The NOAA Environmental Visualization Laboratory has a nice satellite animation of the storm's track superimposed on the NHC's cone of uncertainty forecast.

Well, the official NHC track forecast for Irene was remarkably good; the 5-day forecast was pretty much spot-on for landfall locations, though the timing of when the storm would arrive at the coast was off by a few hours (Figure 1.) This remarkably accurate forecast undoubtedly reduced the costs of unnecessary preparations, and probably saved many lives. NHC track forecasts have improved by over 50% since 1990. The average error in a 24-hour forecast was about 105 miles in 1990, and has averaged near 50 miles the past few years. NHC director Bill Read stated in a interview this week that had Hurricane Irene come along before the recent improvements in track forecasting, hurricane warnings would have been issued for the entire Florida, Georgia, and South Carolina coasts. At an average cost of $1 million per mile of coast over-warned, this would have cost over $700 million. We can credit the investments made in hurricane research, improved satellites, and better computer models for the majority of this improvement. When we consider that government funding for hurricane research has averaged $20 million per year during much of the past two decades, the roughly $200 million spent on hurricane research over the past 20 years was paid back by over a factor of three during just one storm. According to a 2007 presentation at the 61st Interdepartmental Hurricane Conference, the improved hurricane forecasts between 2000 - 2006 resulted in savings of $3 billion compared to what the forecasts of the 1990s would have cost.

What about intensity forecasting?
Progress in making better intensity forecasts of hurricanes, though, has lagged. Over the past twenty years, there has been virtually no improvement in forecasting how strong or weak a hurricane will grow. NHC predicted Irene would hit North Carolina as a Category 3 storm, but it hit at Category 1 strength. Had the intensity forecast been better, many evacuations that were done for Irene could have been avoided. The failure of the intensity forecast led to many accusations that the storm was over-hyped, and an unnecessary amount of expensive preparations and evacuations were done. While I did see some over-hype by the media, I did not think it was more excessive than what has been the case for previous hurricanes. Nate Silver of the New York Times makes some interesting comparisons of the media attention given to Irene versus previous storms, and finds that Irene had about the same amount of media attention as hurricanes Ike and Gustav of 2008. Given in inexperience of the mid-Atlantic and New England coasts with hurricanes, our lack of skill in making intensity forecasts, and the potential for high storm surge damage due to the size of Irene and its landfall during the highest tides of the month, I thought that the overly-cautious approach to evacuations along the coast was warranted.

Better intensity forecasts threatened by budget cuts
Better intensity forecasts of hurricane are possible, but it will take a large investment in hurricane research over an extended time to do that. Such an effort is underway; we are currently in year three of a ten-year program called the Hurricane Forecast Improvement Project (HFIP), funded at just over $1 million per year. The goals of the HFIP are to reduce the average errors of hurricane track and intensity forecasts by 20% within five years and 50% in ten years with a forecast period out to 7 days. In an interview I did last fall with the leader of the project, Dr. Frank Marks of NOAA's Hurricane Research Division, he expressed to me optimism that the program could meet its objectives, provided it remains fully funded. Some of the experimental computer models developed by HFIP have done very well so far during the 2011 hurricane season, so I see reason for optimism, too. However, this project is in serious danger of failure, due to the current budget-cutting emphasis in Washington D.C. A key tool we need to make better intensity forecasts is to have detailed measurements inside the core of the hurricane from instrumented aircraft. Without detailed observations, there is no hope of making a good intensity forecast, no matter how good your model is. During Hurricane Irene, the two P-3 hurricane hunter aircraft and G-IV jet operated by NOAA's Aircraft Operations Center flew continuously into the storm, taking detailed measurements via dropsonde and Doppler radar that were fed in real time to the experimental HFIP computer models. In theory, these measurements by the Hurricane Hunters should be able to significantly improve our intensity forecasts over the coming years. However, the current proposed budget from the House of Representatives mandates a $400 million cut for NOAA, and the NOAA Hurricane Hunters are slated to have their budget cut by 40%, from $29 million to $17 million per year. If these cuts materialize, the ability of the NOAA Hurricane Hunters to continue to aid improvements in hurricane forecasting will be seriously impacted. Many of the critical technologies used operationally now by the Air Force Hurricane Hunters and NOAA jet to improve hurricane forecasts--dropsondes, real-time high-density observations, and the SFMR surface wind measuring instrument--were developed on the NOAA P-3s as research projects, then were migrated to operational use once they proved their worth. The cost of hurricane damages in the U.S. has been doubling every ten years since the 1960s, and is expected to continue to double every ten years, even without the likely coming increase in storm surge damages due to accelerating sea level rise. A Category 1 hurricane doing $10 billion in damage should be a wake-up call that we need to continue our investments in hurricane research to reduce the costs of the inevitable coming storms. Slashing funding by 40% for a research group that was instrumental in saving $700 million in costs from just one storm makes no sense, and I hope Congress will reconsider the proposed cuts for NOAA's Aircraft Operations Center.

References
Whitehead, J.C., 2003: "One million dollars per mile? The opportunity costs of Hurricane evacuation", Ocean and Coastal Management 46, 1069.

Tropical Storm Katia
Tropical Storm Katia continues its long trek across the Atlantic Ocean today, and is expected to arrive at a position several hundred miles north of the Northern Lesser Antilles Islands by Monday. At this time, it appears unlikely that the islands will receive tropical storm-force winds from Katia. Satellite images show that Katia is a well-organized storm with plenty of heavy thunderstorms. The storm has good upper-level outflow channels to the north and south, is under light wind shear, and is traversing warm waters, so it should be able to overcome any dry air problems by Thursday and intensify into a hurricane. It is looking less likely that Katia will affect land. Dr. Bob Hart's Historical Tropical Cyclone Probability web page suggests shows that tropical storms in Katia's current position have an 11% chance of hitting North Carolina, a 12% chance of hitting Canada, a 5% chance of hitting Florida, and a 62% chance of never hitting land. It will be two more days before our computer models will be able to assess the threat to land, though, as Katia is currently still very far out at sea.


Figure 2. The morning run of the GFS Ensemble prediction. The ensemble prediction was done by taking a lower-resolution version of the GFS model and changing the initial distributions of temperature, pressure, and humidity randomly by a few percent to generate an ensemble of 20 different computer projections of where Katia might go. The operational (highest-resolution) version of the GFS model (white line) is usually more accurate, but the ensemble runs give one an idea of the uncertainty in the forecast. Very few of the ensemble members are currently showing a threat to the U.S. Canada is more at risk than the U.S., according to this model.

Gulf of Mexico disturbance a threat to develop
Surface winds over the Gulf of Mexico are rising today in advance of the approach of a tropical wave currently over the Western Caribbean, western tip of Cuba, and Mexico's Yucatan Peninsula. This wave is headed west-northwest at 10 - 15 mph, and is under a high 20 - 30 knots of wind shear. The wave is slowly beginning to build an increased amount of heavy thunderstorms, and this process will accelerate on Thursday when the wave enters the Gulf of Mexico. By Friday, when the wave will be near the Louisiana or Texas coast, wind shear is expected to drop to low to moderate levels, and the wave may be able to organize into a tropical depression. This process will likely take several days, and formation of a tropical depression is more likely Saturday or Sunday. NHC is giving the wave just a 10% chance of developing into a tropical depression by Friday morning. Regardless, this system will spread heavy rains to portions of the Gulf Coast by Friday, with the Upper Texas coast and the coast of Louisiana the most likely recipients of heavy rain. Strong onshore winds raising tides to 1 - 2 feet above normal are likely over Louisiana beginning on Friday, and coastal flood statements have been issued for the region. Three of our four top models for predicting tropical cyclone development forecast that a tropical depression will form this weekend or early next week, and I think it is at least 50% likely we will have Tropical Depression 13 on our hands by Monday. However, steering currents will be weak in the Gulf, and it is difficult to predict where the storm might go.The GFS model has a possible tropical depression forming by Sunday off the coast of Mississippi, then moving east-northeast over the Florida Panhandle on Monday. The ECMWF model forms the storm on Monday off the coast of Texas, and leaves the storm stalled out there through Wednesday. The UKMET model forms the storm Saturday off the coast of Louisiana, and leaves it stalled out there through Monday. If the storm did remain in the Gulf of Mexico for three days as some of the recent model runs have been predicting, it would be a threat to intensify into a hurricane.

Related posts:
Big money for hurricane research? My October 27, 2006 post.

Jason Samenow at the Washington Post has an excellent post, Hurricane Irene hype: over the top media coverage or justified?

Andrew Freedman at the Washington Post talked earlier this month how lack of funding to replace an aging weather satellite may degrade weather forecasts beginning in 2016. Michael Conathan at climateprogress.org had a more detailed analysis of the issue in a February blog post.

Andy Revkin at the New York Times discussed in his Dot Earth blog yesterday how cuts in the USGS stream gauge network will hamper flood forecasting.

Jeff Masters
Lincoln Road
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Hurricane

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

Reader Comments

12z NAM brings 10-20 inches of rain to Southern parts of Louisiana, Mississippi, and Alabama.

P451 "For those following Katia.... that is a fairly hostile environment she's heading into. Also note the large system off of NC moving SE towards her...and not NE the way the models had it heading as of yesterday.
We could see some changes here for Katia's track and intensity forecasts.
."

Already seen Katia's path shift evermore westward over the past 24hours,
from 287degrees(WNW) between 6amGMT and 12pmGMT on 31August...

to 277.1degrees(W) between 6amGMT and 12pmGMT on 1September.

Both of the 4 eastern line-segments represent HurricaneKatia's path
and both of the westernmost line-segments are the straightline projections.
Quoting Patrap:
Orleans
Flash Flood Watch, Coastal Flood Statement
Statement as of 4:03 AM CDT on September 01, 2011

... Flash Flood Watch in effect through Sunday evening...

The National Weather Service in New Orleans has issued a

* Flash Flood Watch for portions of southeast Louisiana and
southern Mississippi...


Bingo!
3004. Patrap
NOLA can Handle a Inch per hour rate the first 2 hours ,after that,,the Pumps can Handle a Half inch rate per hour,,anything more than that rate and street flooding becomes a issue.

I suggest reading up on Juan 1985 to see that scenario,or Allison 2001
A nice big bowl of spaghetti.

3006. HCW
I know that you are dry Texas but you don't need a slow moving or stalled storm like this . I can't imagine 12 to 30 inches on top of surfaces that haven't seen rain in 8 months . Hopefully the models end up being wrong about this system but I have a feeling that next week at this time we will be tired of talking about Lee and wishing that he would go away
Quoting HCW:
I know that you are dry Texas but you don't need a slow moving or stalled storm like this . I can't imagine 12 to 30 inches on top of surfaces that haven't seen rain in 8 months . Hopefully the models end up being wrong about this system but I have a feeling that next week at this time we will be tired of talking about Lee and wishing that he would go away


Yea, mind as well let Louisiana have it all
Interesting wind shift from the SE in the last half hour.Link

Conditions at 42363 as of
(9:30 am CDT)
1430 GMT on 09/01/2011:
Unit of Measure: Time Zone:
Click on the graph icon in the table below to see a time series plot of the last five days of that observation.

Wind Direction (WDIR): W ( 280 deg true )
Atmospheric Pressure (PRES): 29.97 in
Air Temperature (ATMP): 78.1 °F
Dew Point (DEWP): 73.0 °F
Heat Index (HEAT): 80.6 °F
3009. JNCali
Quoting HCW:
I know that you are dry Texas but you don't need a slow moving or stalled storm like this . I can't imagine 12 to 30 inches on top of surfaces that haven't seen rain in 8 months . Hopefully the models end up being wrong about this system but I have a feeling that next week at this time we will be tired of talking about Lee and wishing that he would go away

Morning all!... With heavy rain in TX, at least the reservoirs and lakes would be helped -right?
Wishcasters?  LOL  This is a big weekend for the tourist industry, my only wish is that the storm would disappear or make a beeline for TX - I have family near the fires...  Regardless we  on the FL Pandhandle will most likely see coastal flooding & beach erosion.
Quoting Junior88:
Lots of Eastern GOM States wishcasters in here when only a few models show it. Texas needs the rain more than you.

$$
FORECASTER CANGIALOSI/ZELINSKY

Nice to have some new, young blood in there. Don't worry though. As Katia begins her westward job closer to land, forecasters Avila and Stacy Stewart will be back manning the controls...
FIM shows Katia making landfall near Cape Hatteras, NC on the 10th of September! WOW DEJA VU?

3013. ackee
KATIA seem to weaking and moving west at least for now mother nature is so hard to predict at times
I wish WeatherUnderground had a feature where you can read all the comments you have posted (just you).

11:00am Advisory
*Click graphics to magnify (Graphics can also be magnified more by clicking on them in the Link window)


3015. HCW
Quoting Beachfoxx:
Wishcasters?  LOL  This is a big weekend for the tourist industry, my only wish is that the storm would disappear or make a beeline for TX - I have family near the fires...  Regardless we  on the FL Pandhandle will most likely see coastal flooding & beach erosion.



And don't forget that you will also see lots of Oil washing up but nobody wants to talk about that :(
Just looking at the latest NGP Hurricane model run,the Bermuda High close all the way into the USA at the end of the run when Hurricane Katia still below Longitude 26 is this is the case it will probably block Katia from going North and send it into a more West track.Any comments about this observation please.Thanks!!!
3017. 996tt
Quoting Junior88:
Lots of Eastern GOM States wishcasters in here when only a few models show it. Texas needs the rain more than you.


Haha, getting territorial with the storm. It's mine . . . You cannot have. I think we need a good swell here in Destin area so I can surf at home instead of so much travel so I think I need it worse than you. Kidding aside, we should get our swell even better if it just stays down that direction and spins in the GOM for a while.
3018. P451
Quoting Joshfsu123:


True - and the current ULL near Katia is pushing the dry air into the core - similar to what the ULL in the Gulf did to Irene. That is always hard to forecast.


Very.

One outlier could be that Katia weakens and slips more southerly/westerly underneath those ULLs. She could get left behind by the trof. She would be very weak but would be left to possibly restrengthen and be a player for the SE US/Mid Atlantic.

I could see that, but I wouldn't expect it at this time.

Have to see how the ULLs progress today before making that type of call - specifically the NC entity.

To a degree I think this may be what some have been saying about giving Katia 2-3 days (as of yesterday morning) before the models would have a good handle on her. Perhaps this was foreseen by some.
Allison turned the GOM red here in Destin... from the rivers & streams north of us, I remember seeing rabbits, squirrels and other things floating in that red tainted water...
Quoting Patrap:
NOLA can Handle a Inch per hour rate the first 2 hours ,after that,,the Pumps can Handle a Half inch rate per hour,,anything more than that rate and street flooding becomes a issue.

I suggest reading up on Juan 1985 to see that scenario,or Allison 2001

Quoting redwagon:

Is anybody analyzing the Panama system yet?


Morning, Redwagon....just came on....I see what your talking about....wish I had more skills to analyze,.... but I'm sure some of these guys that do, are on top of it.
That's a train of thought I would like to avoid... but it is a major concern.  Friends recently did a dive expedition & their results were quite disturbing.
Quoting HCW:


And don't forget that you will also see lots of Oil washing up but nobody wants to talk about that :(

3022. Patrap
3023. 7544
katia is moving due west at 20 mph hmmmmm
3024. MahFL
Quoting thewindman:
Question, Would New Orleans go underwater again with Lee? Not from the wind but the amount of rain possibly 20 inches in 3-4 days.


If you mean like with Katrina, no, unless a canal wall or levee fails like last time, then yes...sadly....
3025. Patrap
Quoting Hurricane1956:
Just looking at the latest NGP Hurricane model run,the Bermuda High close all the way into the USA at the end of the run when Hurricane Katia still below Longitude 26 is this is the case it will probably block Katia from going North and send it into a more West track.Any comments about this observation please.Thanks!!!


I asked the same question 3 days ago but nobody answered me so I thought I was not reading the models correctly and was asking a stupid question
3027. Jax82
There is a circulation directly south of Louisiana, and it appears there is another one under the convection to the Southeast of that circulation. You can see the clouds streaking north at the bottom of this zoomed in visible animation

GOES Zoomed In Vizzy
3028. Patrap
3029. angiest

Quoting JNCali:

Morning all!... With heavy rain in TX, at least the reservoirs and lakes would be helped -right?
It has to fall at least a hundred miles inland (roughly, and in some instances much further) to make it into the reservoirs for south Texas.
Looks like 93L is going to be quite a soaker for NOLA, leaving Texas hot n' dry.

I've made the decision to rip out my dead grass and replace with rock. It'll be the only yard in Houston with desert landscaping!
3031. Patrap
New Orleans
NEXRAD Radar

Type
Velocity Azimuth Display Wind Profile ° Elevation
Range
124 NMI

Note the Winds and Heights last Frame


3032. Jax82
Ummm, thats alotttttta rain. 5 day QPF, taste the rainbow.



GOES Zoomed In Vizzy
Quoting Patrap:


Wow, look at all that shear out ahead of Katia.
Quoting Jax82:
There is a circulation directly south of Louisiana, and it appears there is another one under the convection to the Southeast of that circulation. You can see the clouds streaking north at the bottom of this zoomed in visible animation

GOES Zoomed In Vizzy


It is an eddy, this thing is just starting to get organized, this is very typical of tropical storms forming from upper-level lows.
3035. russm1
Quoting Beachfoxx:
Friends recently did a dive expedition & their results were quite disturbing.



Care to expand on that please?
3036. 996tt
Quoting Patrap:
NOLA can Handle a Inch per hour rate the first 2 hours ,after that,,the Pumps can Handle a Half inch rate per hour,,anything more than that rate and street flooding becomes a issue.

I suggest reading up on Juan 1985 to see that scenario,or Allison 2001


Yes. Not a good scenario for you guys.
Any chances that West Central FL (St Petersburg) stays dry this weekend if the system stays far enough to our West?
Quoting Beachfoxx:
make a beeline for TX - I have family near the fires...

Careful what you wish for. The winds will probably make the fires worse before the rain gets there, if it gets there at all. I had a nerve wracking experience with a neighbor trying to dispose of a horse carcass by setting it on fire the day before Rita's arrival.
3039. HCW
Nobody is talking about this but it's going to be a major problem is all the oil that is on the floor of the GOM from the oil spill . It's still there don't let B.P brainwash you into thinking that it's all gone. I have friends who dive and there is lots of it still out there and it's still washing up on our beaches. Lee will bring it up into bays and rivers and other places that never expected to see oil
Quoting TXMegaWatt:


We need the rain so bad though. Could do without the wind and storm surge though. I'm afraid all of the dying trees in Texas might not withstand hurricane force winds.


Didn't think about that....lots of dead & dying trees would uproot with minimal gusts. But without rain...they'll keep dying anyway. Don't need 20".....just some moist air, something! I'll be eating crow if we get a major storm, but at this point it's hard not to wish for it to come our way.
3041. Drakoen
Things getting very interesting with 93L. Satellite images show a broad area of low pressure forming south of Louisiana oriented SW to NE. Water vapor imagery shows a small upper level cyclone over Louisiana moving westward and as it does so conditions will gradually become more favorable for 93L to develop into a tropical cyclone. The potential exists for a significant home-grown cyclone to form as the the steering becomes weak causing variable motion of 93L. I counted about two loops on the ECMWF with 93L before it finally makes landfall along the northern Gulf Coast. Both the track forecast and the intensity will be highly uncertain with this system with reliable models going through day to day changes on both the track and intensity of 93L. I think there is a good chance for a significant cyclone to form and impact the U.S.
I'd rather not, at this time...  from what I understand they are waiting for some results from labs.  Apparently *shock & surprise* there is a layer of oil on the GOM floor in some areas.
Quoting russm1:


Care to expand on that please?

ASCAT caught 94L this morning..
Quoting Beachfoxx:
Morning Viking,

Yep, looks like our boating & Crab Island plans are kaput... dang, I was looking forward to a boat meet!



Yeah me too, we really need this mess to push West and give TX the relief it needs. Didn't our Labor Day weekend get messed up last year too or was it the year before?
Quoting HCW:
Nobody is talking about this but it's going to be a major problem is all the oil that is on the floor of the GOM from the oil spill . It's still there don't let B.P brainwash you into thinking that it's all gone. I have friends who dive and there is lots of it still out there and it's still washing up on our beaches. Lee will bring it up into bays and rivers and other places that never expected to see oil


How deep is the water out there? I wouldn't expect a hurricane to affect it if it's deeper then 200 feet.
Quoting 996tt:


Yes. Not a good scenario for you guys.
I think we all remember Juan, and if you go back a few pages there was some discussion of whether the Corps of Clowns Engineers will close the storm gates on the outfall canals, severely restricting that half an inch an hour capability. The promised "efficient and torrential" rains forecast for NOLA are going to make a mess. Better grab your parking spot on the neutral ground while you still can.

No, NOLA will not go under like Katrina. We there will be significant street flooding and a lot of cars and slab-on-grade homes in trouble if we get substantial rain.
Quoting bluheelrtx:
Careful what you wish for. The winds will probably make the fires worse before the rain gets there, if it gets there at all. I had a nerve wracking experience with a neighbor trying to dispose of a horse carcass by setting in on fire the day before Rita's arrival.


Post of the day!
3048. beell
As would be expected, rig locations S and E of the Mississippi River reporting S/SE winds. West of the river, NE/ENE winds.

Most all of them around 25 knots, gusting up to 35 knots.

Google earth KML file (rigs, buoys, coastal stations, etc)
3049. Patrap
BP's Macondo Well is 5000 ft below the surface,,no entity is saying the well is Leaking,,we have seepage all the Time, so take any reports of the BP well with a grain o tabasco.

Billy Nunguesser would be on them Like white on Rice if they thought that.
Oceansat's pass of Talas about to smack Japan..

Quoting HCW:
I know that you are dry Texas but you don't need a slow moving or stalled storm like this . I can't imagine 12 to 30 inches on top of surfaces that haven't seen rain in 8 months . Hopefully the models end up being wrong about this system but I have a feeling that next week at this time we will be tired of talking about Lee and wishing that he would go away


At this point, we will take anything we can get. Talking to farmers in the area is so depressing. Hay crops have turned out to be a true disaster this year. They have no crop to sell or feed their own animals with. It's a sad sight to see.

If we can get some heavy rains now, a late fall hay cut may prove to be fair instead of non-existant.
Quoting Drakoen:
Things getting very interesting with 93L. Satellite images show a broad area of low pressure forming south of Louisiana oriented SW to NE. Water vapor imagery shows a small upper level cyclone over Louisiana moving westward and as it does so conditions will gradually become more favorable for 93L to develop into a tropical cyclone. The potential exists for a significant home-grown cyclone to form as the the steering becomes weak causing variable motion of 93L. I counted about two loops on the ECMWF with 93L before it finally makes landfall along the northern Gulf Coast. Both the track forecast and the intensity will be highly uncertain with this system with reliable models going through day to day changes on both the track and intensity of 93L. I think there is a good chance for a significant cyclone to form and impact the U.S.


Certainly are a lot of variables. I had to chuckle a bit when I saw the Euro bombed the pressure down to 930mb before making landfall in Central Louisiana.
Quoting cat5hurricane:
$$
FORECASTER CANGIALOSI/ZELINSKY

Nice to have some new, young blood in there. Don't worry though. As Katia begins her westward job closer to land, forecasters Avila and Stacy Stewart will be back manning the controls...
Katia is moving west?For how long? Is that the case the northern islands could be in trouble.
How will 93L "bomb out" if the shear looks like this:

3055. Patrap
Tracking Information from the NHC

NHC Advisory : 14
Name : KATIA
Type : HURRICANE (Category 1)
Position : 15.5, -47.5
Heading (degrees) : 280
Motion Speed (kts) : 16
Central Pressure (mb) : 987
Maximum Sustained Winds (kts) : 65
Maximum Wind Gusts (kts) : 80
Valid time : 15:00:00 GMT, September 01, 2011
Quoting Junior88:
Lots of Eastern GOM States wishcasters in here when only a few models show it. Texas needs the rain more than you.


Shows how clueless you are. None of us here in the Eatern GOM care to see 93L come our way. We live on the beach and have a 3 day weekend coming up, we want to take out boats and enjoy one of the last weekends of the summer WITHOUT rain! Go to Texas 93L, NOW!
Looking at the latest model runs for 93l it seems that most of the main ones other than the HWRF are now in agreement with what the ECMWF has been predicting since yesterday. The storm forms and approaches Louisiana and then runs SW along the Texas coast before moving inland over central to S. Texas.

Hopefully whatever forms stays near land. If it sits out over open water for any amount of time it's going to become big and scary.
With all that shear out ahead of Katia, it may hamper her intensification, which will keep it more south on a westerly track.
3059. Jax82
11am update. She's not going anywhere fast, next Tuesday she's only forecasted to be north of PR.

Quoting weathers4me:
Any chances that West Central FL (St Petersburg) stays dry this weekend if the system stays far enough to our West?


It will not be dry in West Central Florida this weekend. Even disregarding 93L, we are forecast to have afternoon thunderstorms each and every day through the seven day period.40-50% chance.
When will they be flying into 93L to get a better look?
3062. HCW
Quoting nolacane2009:
When will they be flying into 93L to get a better look?


After 1pm today
You guys must have seen a later run of the ECMWF. I'm just repeating what the local NWS office has stated. Do you have a link?
Starting to see that troublesome bend back left in the 5 day for Katia
Quoting HCW:


After 1pm today


Thank you
38mph gust offshore SE of LA
3067. nash28
Hmmmmm...

Will be curious to see if the trough flattens out and scoots out thereby not having much of an affect on Katia.
Quoting E46Pilot:
With all that shear out ahead of Katia, it may hamper her intensification, which will keep it more south on a westerly track.
Who said that.Shear may cause a different track?
Morning everyone!

Just a reminder, you can check out photos of Irene's flooding in NJ that I posted yesterday on my blog.

Also, the term of the day is squashed spider.

3070. cmagag
Quoting Fraidycat:
Looking at the latest model runs for 93l it seems that most of the main ones other than the HWRF are now in agreement with what the ECMWF has been predicting since yesterday. The storm forms and approaches Louisiana and then runs SW along the Texas coast before moving inland over central to S. Texas.

Hopefully whatever forms stays near land. If it sits out over open water for any amount of time it's going to become big and scary.


Hopefully it stays close to land because WE NEED FREAKING RAIN!!!!!!!
Someone please consider my thoughts and let me know if you think they have any merit.

Katia weakens considerably due to dry air, shear; whatever, it just weakens. The through to her north weakens as well and the high builds in. Ok, with all that, should it happens, a weakened Katia is not picked up by the hypothetical weakened trough, and since she is blocked north by the ever-expanding Bermuda High. she therefore she continues west, I mean Islands or FL west. Anyone care to comment, if I am talking out my rear? or is there any merit to my assessment.
3072. Jax82
KATIA IS MOVING WESTWARD OR WWW TOWARD CAYMAN AT 16 KT TO THE SOUTH OF A SUBTROPICAL
HIGH. THE HURRICANE IS EXPECTED TO SLOW DOWN AND TURN TO THE
WEST-NORTHWEST DURING THE NEXT 12-24 HOURS AS IT APPROACHES A
WEAKNESS IN THE RIDGE. THE MODEL GUIDANCE BECOMES VERY DIVERGENT IN
4 TO 5 DAYS WITH THE UKMET...NOGAPS...AND GFDL MODELS ON THE SOUTH
SIDE OF THE ENVELOPE AND THE GFS...ECMWF...AND HWRF MODELS ON THE
NORTH SIDE. THIS SPREAD APPEARS TO BE ASSOCIATED WITH THE STRENGTH
OF A TROUGH MOVING OVER THE NORTHEASTERN UNITED STATES AND THE
POSITION OF THE SUBTROPICAL HIGH. THE OFFICIAL TRACK FORECAST IS
ONLY NUDGED A LITTLE TO THE LEFT...IN PART BECAUSE OF THE INITIAL
MOTION AND POSITION...AND IS VERY NEAR THE MULTI-MODEL CONSENSUS.

FORECAST POSITIONS AND MAX WINDS

INIT 01/1500Z 15.5N 47.5W 65 KT 75 MPH
12H 02/0000Z 16.1N 49.5W 70 KT 80 MPH
24H 02/1200Z 17.0N 51.7W 75 KT 85 MPH
36H 03/0000Z 18.0N 53.4W 85 KT 100 MPH
48H 03/1200Z 19.0N 55.0W 95 KT 110 MPH
72H 04/1200Z 20.8N 58.0W 100 KT 115 MPH
96H 05/1200Z 22.3N 61.0W 105 KT 120 MPH
120H 06/1200Z 23.8N 64.0W 105 KT 120 MPH
Ditto!
Quoting 69Viking:


Shows how clueless you are. None of us here in the Eatern GOM care to see 93L come our way. We live on the beach and have a 3 day weekend coming up, we want to take out boats and enjoy one of the last weekends of the summer WITHOUT rain! Go to Texas 93L, NOW!

Quoting HCW:


After 1pm today


LOCAL mets are saying they are taking off at 1030am cdt...
3075. BrandiQ
Quoting wxobsvps:
Starting to see that troublesome bend back left in the 5 day for Katia


Ya I'm not liking that at all... I'm hoping it will rebend out to sea...
Quoting prcane4you:
Who said that.Shear may cause a different track?


Shear itself wouldn't cause a different track. Shear would stop intensification, which would tend to cause more of a westerly track.
They're topping off the tank and checking the oil on the 12Z GFS, should get the green flag in about 10 minutes or so. After the 6Z flop in track from 00Z, will be an interesting run to see if comes back in line with 00Z Euro, which also flopped.
3078. nash28
Quoting Clearwater1:
Someone please consider my thoughts and let me know if you think they have any merit.

Katia weakens considerably due to dry air, shear; whatever, it just weakens. The through to her north weakens as well and the high builds in. Ok, with all that, should it happens, a weakened Katia is not picked up by the hypothetical weakened trough, and since she is blocked north by the ever-expanding Bermuda High. she therefore she continues west, I mean Islands or FL west. Anyone care to comment, if I am talking out my rear? or is there any merit to my assessment.


Well, not THAT far west. I don't see the AB High nosing itself into the CONUS preventing any poleward movement. Having said that, I also do not see the ridiculous trough amplification in August that the GFS is in love with. Much closer approach to the ECONUS.
Quoting HCW:
Nobody is talking about this but it's going to be a major problem is all the oil that is on the floor of the GOM from the oil spill . It's still there don't let B.P brainwash you into thinking that it's all gone. I have friends who dive and there is lots of it still out there and it's still washing up on our beaches. Lee will bring it up into bays and rivers and other places that never expected to see oil


There may be areas of the ocean floor that still have Oil but I don't see a tropical system bring the oil up from 100' - 1000' below the surface. I've also seen studies done where a tropical system now could actually benefit by breaking up the oil and further helping to disolve and evaporate it. I patrol the beaches for Sea Turtle nests and trust me when I say there isn't any oil washing up on the beaches as of late. There may be an isolated incident ocassionally but our beaches are as white and beautiful as ever! Despite the scare tactics by some it appears the tourists have returned to our area. Go West 93L, Go West!
Looks like LLC south of NOLA moving westbound on visibles
You know, I think it did - last year.  Let me check...

Quoting 69Viking:


Yeah me too, we really need this mess to push West and give TX the relief it needs. Didn't our Labor Day weekend get messed up last year too or was it the year before?

Opinion wanted: Is it just me or does it appear Katia has been going more West the past few days than expected? It does appear that it will not affect the Leewards, but not so sure on a sharp Northerly turn. Anyone have any thoughts or facts about its motion in the next few days (preferably North)?
ECMWF 168hrs.


CMC 96hrs


GFS 114hrs


UKMO 120hrs


GOM System has all the models confused.
Quoting Clearwater1:
Someone please consider my thoughts and let me know if you think they have any merit.

Katia weakens considerably due to dry air, shear; whatever, it just weakens. The through to her north weakens as well and the high builds in. Ok, with all that, should it happens, a weakened Katia is not picked up by the hypothetical weakened trough, and since she is blocked north by the ever-expanding Bermuda High. she therefore she continues west, I mean Islands or FL west. Anyone care to comment, if I am talking out my rear? or is there any merit to my assessment.
Agree.If Bermuda High continue to expanding to the west Katia will go west to the islands.
Quoting Fraidycat:
You guys must have seen a later run of the ECMWF. I'm just repeating what the local NWS office has stated. Do you have a link?


Link
I agree!  Go west!  Yes, our beaches are sugar white... tourist are back & we really were hoping for a good weekend. 
Quoting 69Viking:


There may be areas of the ocean floor that still have Oil but I don't see a tropical system bring the oil up from 100' - 1000' below the surface. I've also seen studies done where a tropical system now could actually benefit by breaking up the oil and further helping to disolve and evaporate it. I patrol the beaches for Sea Turtle nests and trust me when I say there isn't any oil washing up on the beaches as of late. There may be an isolated incident ocassionally but our beaches are as white and beautiful as ever! Despite the scare tactics by some it appears the tourists have returned to our area. Go West 93L, Go West!

Pressures are not noticeably dropping in the Eastern Gulf.

Quoting EYEStoSEA:

Yep, that Panamanian system already has spin.
Quoting MississippiWx:
12z NAM brings 10-20 inches of rain to Southern parts of Louisiana, Mississippi, and Alabama.

Yeah, not liking this NAM run...go west, please.

I need rain, but not that much and preferably not this weekend.
3091. 996tt
Quoting JupiterFL:


Post of the day!


I know. So true. Their fires will get spread by winds and rain will skirt them.

Burning a horse carcus. What the . . .? Sounds like some back woods hillbilly stuff not to mention nasty smell I bet. I thought people got back hoes and hurried dead horses or something in the 21st century.
Quoting E46Pilot:


How deep is the water out there? I wouldn't expect a hurricane to affect it if it's deeper then 200 feet.


You hit 100' 10 miles or less offshore and then 200' when you approach 20 miles offshore. Shortly after that the GOM drops to several hundred feet off our shores in NW FL. I honestly don't think the oil is going to be a problem, I'm more worried about coastal flooding and the risk to Sea Turtle nests that still haven't hatched.
Katia's center is on the verge of becoming exposed and is now outrunning what remains of the storm's CDO. If this continues the system may wind up being downgraded to a TS at 5 today. There is no question that the deep convection is all but gone and a decoupling of the low and mid level centers later today is also a possibility if current trends continue IMO.
Man, look at the Yucatan Channel...

3095. usa777
I think god has finally begin to watch over me..lol. I left to go on vacation last Tuesday the 23rd and we had a 5.8 magnitude quake here and follow that up with Irene and I was on vaction the whole time. Here is the kicker. My power was out for 4 days and just as I pull up in my driveway the power comes back on. Tell me that man is looking out for me. lol. I got tested in Katrina so he must be thinking "that dude has been dealt quite enough"..lol
Quoting naplesdreamer28:
Opinion wanted: Is it just me or does it appear Katia has been going more West the past few days than expected? It does appear that it will not affect the Leewards, but not so sure on a sharp Northerly turn. Anyone have any thoughts or facts about its motion in the next few days (preferably North)?

well, the CMC ensemble has another east coaster in 216hrs.

Quoting Patrap:
BP's Macondo Well is 5000 ft below the surface,,no entity is saying the well is Leaking,,we have seepage all the Time, so take any reports of the BP well with a grain o tabasco.

Billy Nunguesser would be on them Like white on Rice if they thought that.


Nunguesser has aspirations for higher office, and by now must realized you can't be elected constable on an anti-oil platform in Louisiana. Now that Corporations Are People, Too, they will bury anyone who stands up to them in money.

And I have zero confidence in the CG command structure since they made themselves BP's security mercenaries last year, so anything the CG says is as discounted as if it came from the mouth of BP.

But put aside the current large slick and sheen that will be washing ashore in the next few days. Think about all the oil the Corexit cleverly deposited on the bottom or in subsurface plumes so we wouldn't see it. And the Corexit.

Thinking of picking up a Tyvex suit this afternoon.

Viking,

How many nest have you seen on the area you patrol?
Quoting 69Viking:


You hit 100' 10 miles or less offshore and then 200' when you approach 20 miles offshore. Shortly after that the GOM drops to several hundred feet off our shores in NW FL. I honestly don't think the oil is going to be a problem, I'm more worried about coastal flooding and the risk to Sea Turtle nests that still haven't hatched.

Quoting TerraNova:
Pressures are not noticeably dropping in the Eastern Gulf.



CMC 06Z analysis shows a broad low with a 1008 mb centre over the central gulf...no obs in the vicinity, though, to support it. Link
3100. Drakoen
It is interesting to see how some of the models have shifted to the south and west with Katia. The UKMET, NOGAPS, GFDL, and HFIP-hWRF on the south and west side of the track and the ECMWF, GFS, and HWRF on the north and right side of the track. Katia's low level center is struggling to maintain convection as she is encountering the region of upper level confluence between her upper level high and the upper level low to her northwest. This may keep Katia on a more westerly based track since a weaker system would be less prone to the Beta effect. It should be noted that there is a high standard deviation with the ECMWF ensemble members as the operational lies on the northern side of the individual ECMWFEPS members.
3101. linkays
Quoting TXMegaWatt:


At this point, we will take anything we can get. Talking to farmers in the area is so depressing. Hay crops have turned out to be a true disaster this year. They have no crop to sell or feed their own animals with. It's a sad sight to see.

If we can get some heavy rains now, a late fall hay cut may prove to be fair instead of non-existant.


I couldn't agree more. People with livestock (also wildlife) are desperate for rain that it doesn't matter how we get it. Recently had someone dump a newborn donkey (we raise them) on me and sadly it died. The last round hay bales I bought were $100 each and even higher now. So tired of seeing dead deer (adults & fawns) hit by cars and killed because they're seeking water. There is a huge pond in the pasture next to ours that is completely dry! Maybe I'm wish casting but at this point I don't care....I'll take whatever will come here to South Texas!
Quoting TerraNova:
Morning everyone!

Just a reminder, you can check out photos of Irene's flooding in NJ that I posted yesterday on my blog.

Also, the term of the day is squashed spider.

Dunno, looks like slug tracks to me. Maybe we should all sprinkle some salt in front of the storm.
The 26 degree isotherm extends more than 100 meters below the surface of the sea in the Yucatan Channel.

If we ever have a system shooting the Channel from the south this year, things could get ugly.

3105. duranta
Wetbankguy, you speak the truth. Massive amounts of oil and corexit sit on the Gulf floor. The well is still leaking, so you know they are still applying the corexit. They never stopped. This is going to wash up into the marsh with these flood warning. The disaster is not over.

I live on the West Bank in Gretna. Where are you?
Quoting kmanislander:
Katia's center is on the verge of becoming exposed and is now outrunning what remains of the storm's CDO. If this continues the system may wind up being downgraded to a TS at 5 today. There is no question that the deep convection is all but gone and a decoupling of the low and mid level centers later today is also a possibility if current trends continue IMO.
Is that due to shear and dry air Kman?
3107. HCW
93L 12Z model runs from the NHC... What a mess !


Quoting linkays:


I couldn't agree more. People with livestock (also wildlife) are desperate for rain that it doesn't matter how we get it. Recently had someone dump a newborn donkey (we raise them) on me and sadly it died. The last round hay bales I bought were $100 each and even higher now. So tired of seeing dead deer (adults & fawns) hit by cars and killed because they're seeking water. There is a huge pond in the pasture next to ours that is completely dry! Maybe I'm wish casting but at this point I don't care....I'll take whatever will come here to South Texas!


The other day, UK or some European country shipped dogs by plane to Houston, they were to be transferred to San Antonio by truck for training. 2 died in the back when the AC went out and most of them were almost dead by the time they found out when pulled over on I-10 just outside of Houston, never even made it past Columbus I think.
Quoting TerraNova:
Morning everyone!

Just a reminder, you can check out photos of Irene's flooding in NJ that I posted yesterday on my blog.

Also, the word of the day is squashed spider.

Geepers.

It's a good reminder that until there's a well-defined center of circulation, the models are of decidedly little use. Models rely on data, and at the moment, they're using projections of where the storm will form instead of an actual storm.

It'll be very interesting to see if anything actually coalesces out of this mess, and if so, where it moves. For now, it's best to ignore these models altogether, at least until they start to come into line. They plainly have no handle on the situation.
Quoting HurricaneNewb:
Is that due to shear and dry air Kman?


Yes, plus the fast forward speed to the West
Quoting 69Viking:


You hit 100' 10 miles or less offshore and then 200' when you approach 20 miles offshore. Shortly after that the GOM drops to several hundred feet off our shores in NW FL. I honestly don't think the oil is going to be a problem, I'm more worried about coastal flooding and the risk to Sea Turtle nests that still haven't hatched.


It's not just the tarballs we're looking for, it's the hydrocarbon components:

http://www.scientificamerican.com/article.cfm?id= masive-oil-plume-confirmed-in-gulf-of-mexico

And what exactly happens to Corexit after its sprayed?

The corporate media aren't interested in telling you the stuff that makes your SUV go is killing people down here, but there's an Agent Orange scale health crisis brewing among response workers, and we don't need a whole lot of other goodies getting blown inland.

Kman,

probably a crazy question but do you see Katia moving west towards the Florida peninsula or somewhere on the SE coast with it being a weaker system and a building bermuda high above? thanks
3113. WxLogic
12Z GFS Init:
3114. Levi32
What a headache 93L is going to be to forecast lol. At any rate let's hope for a quick movement inland into Texas or Louisiana before the weekend is out, or else we may be dealing with a significant tropical cyclone early next week after the system has been sitting over 31C water for 4-5 days.
Getting N and NE breeze here in SE TX, clouds coming from that direction as well, usually the sign of something offshore
Quoting TerraNova:
Morning everyone!

Just a reminder, you can check out photos of Irene's flooding in NJ that I posted yesterday on my blog.

Also, the term of the day is squashed spider.



Ok, but that's two words, "squashed spider" but who's counting.

I was born in in VT, Rutland, where some very heavy flooding occurred, like in NJ. Very bad scene for all my remaining family there. The last thing anyone needs, baring a good soaking for TX is another Irene type storm, this season.

RE: edit, I now see, term of the day.
3117. Jax82
Ok fine i'll do it. NEW BLOG
Something low level trying to form south of LA, moving west
3119. jpsb
Quoting nash28:


Well, not THAT far west. I don't see the AB High nosing itself into the CONUS preventing any poleward movement. Having said that, I also do not see the ridiculous trough amplification in August that the GFS is in love with. Much closer approach to the ECONUS.
Looks to me like K is 12 hrs away from meeting a huge ULL that is feeding her dry air (she is already ingesting some dry air) and shearing her to pieces, once she get by that there is another big ULL. If she is not pulled north there will not be much left of her to go west.
Quoting kshipre1:
Kman,

probably a crazy question but do you see Katia moving west towards the Florida peninsula or somewhere on the SE coast with it being a weaker system and a building bermuda high above? thanks


Several of the models show Katia pushing much closer to the Bahamas than before with a bend back to the West just N of PR. A lot can, and likely will happen, with Katia before 60W that could influence whether it recurves as expected or makes its way farther West before recurving. With the deterioration we are seeing now, if Katia becomes a much weaker TS with an exposed low level center trucking off to the West the models will likely respond in kind once again.

The next 12 to 24 hours will be critical in determining whether Katia recovers, deepens and pushes poleward as per the GFS or weaknes further, pushes more to the W and possibly threaten the Leeward Islands first.

As far as Florida is concerned Katia is still too far out and in too much a state of flux to draw any conclusions regarding the SE coast of the US.
Quoting nash28:


Well, not THAT far west. I don't see the AB High nosing itself into the CONUS preventing any poleward movement. Having said that, I also do not see the ridiculous trough amplification in August that the GFS is in love with. Much closer approach to the ECONUS.


I think the chances of Katia coming anywhere near the CONUS are getting even slimmer than yesterday. It would not surprise me to see a track farther SW in the day 3-6 period given some of the model guidance on track and strength of the ridge - but given increasing consensus toward a big positively tilted longwave trough developing over the eastern CONUS toward the end of the period, it is hard to see how even with a farther SW track in the shorter term this system can avoid full recurvature well E of the East Coast.
3122. CJ5
Quoting 69Viking:


There may be areas of the ocean floor that still have Oil but I don't see a tropical system bring the oil up from 100' - 1000' below the surface. I've also seen studies done where a tropical system now could actually benefit by breaking up the oil and further helping to disolve and evaporate it. I patrol the beaches for Sea Turtle nests and trust me when I say there isn't any oil washing up on the beaches as of late. There may be an isolated incident ocassionally but our beaches are as white and beautiful as ever! Despite the scare tactics by some it appears the tourists have returned to our area. Go West 93L, Go West!


Thanks for that. I agree, the scare tactics by many, especially the media is to blame for much of the economic loss in the gulf states.
well, the 12z gfs is displaying it's data. Let's see the latest it has in store for us.
Lol don't think this one will go to Texas .. Looking at maps Texas will be spared IMO. Anyone from louisianna to Florida need to watch carefully. Texas too but the way it is setting up (everything in eastern gulf) I highly doubt it will make it to Texas.
Quoting Levi32:
Good morning.

Blog update:

Tropical Tidbit for Thursday, September 1st, with Video


Great briefing, Levi. To paraphrase Churchill, the evolution of potential Lee remains an enigma wrapped in a mystery. One thing i'd like to see reviewed is the track problem with a weakened Katia. Cheers.
thanks Kman! what about the changing upper level high pressure pattern evolving towards mid september?

probably a better chance for the SE CONUS

11:00am Advisory
*Click graphics to magnify (Graphics can also be magnified more by clicking on them in the Link window)

I know I have been downcasting 93L as far as tracking into Texas and I still believe that to be the case. Of course I SWORE to my wife that Ike was no threat to us as it would curve out to sea or be an East coast hit.

So even though I believe 93L will be going east to Louisiana or even as far as the Florida Panhandle it would be foolish of me not to take stock and be prepared and I would suggest everyone along the Gulf Coast does as well. Stuff in the Gulf has to hit somewhere.

So I will make sure the cars are full of gas tonight but hold off on the generator gas, water and food we always have with day one of the season. And if this thing comes even close to me, I have a tree that I HATE that I have a feeling will go down in a safe direction in the storm. (No matter what wind direction that baby is falling) My wife likes the tree but it is a Tallow which is a weed here in TX and while the shade is nice it is starting to effect my Magnolia which I like much more.

I counted 3 dead Magnolia trees this morning within 3 blocks of my house and I do not want to be number 4.
3130. IKE
102 hr. 12Z GFS...


Rigs in the GOM are starting to shut down and evacuate which means gas will be more expensive tomorrow. I would fill up today and save a few bucks.
Quoting IKE:
102 hr. 12Z GFS...




with the trough in front right ike
Quoting Levi32:
Good morning.

Blog update:

Tropical Tidbit for Thursday, September 1st, with Video
Just got a chance to watch the video today. Thank you Levi, absoultely fantastic explanation on the trough/ridge setup and how it could effect these storms. Keep up the excelent work, you make Mets wish they had skills like that! =)
Seems the models are clustering on LA,MS and FL now?
3135. SLU
3136. SLU
3137. Inyo
I live in Vermont and we just drove through an area today where Irene's effects are still VERY evident. It was not good, not good at all.

Sadly, peoples attempts to 'fix' the rivers after the flooding did a ton more damage, and made future flood risk even worse.

People are dumb. Most people in Vermont have a lot of down-to-earth common sense, but after a disaster, when people are panicked, people make dumb decisions.