Three Atlantic threat areas may develop; a record fire season for the U.S.

By: Dr. Jeff Masters , 2:43 PM GMT on August 20, 2012

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A large tropical wave (Invest 94L) located about 1100 miles east of the Lesser Antilles Islands is headed west at 20 - 25 mph, and is showing increasing organization today. The storm is under light wind shear of 5 - 10 knots, and is over waters of 27°C. A large area of dry air lies just to the north of 94L, as seen on the latest Saharan Air Layer (SAL) analysis and water vapor satellite loops. This dry air is interfering with development, and this morning's visible satellite loop shows that 94L's heavy thunderstorm activity is sparse. However, the satellite loops do show that 94L has now separated from the clumps of heavy thunderstorms to its south, and a pretty well-defined surface circulation has developed. Heavy thunderstorms are now attempting to fire up around this circulation center, but are being hampered by dry air. The center of 94L was about 80 miles to the north of buoy 41041 at 10 am Monday morning, and the buoy recorded SW winds of 10 mph, confirming that 94L probably does have a closed surface circulation. The disturbance will have to build and maintain more heavy thunderstorms than it has now to be considered a tropical depression, though. The first hurricane hunter mission into 94L is scheduled for Tuesday afternoon.


Figure 1. Morning satellite image of Invest 94L.

Forecast for 94L
The latest 8 am EDT run of the SHIPS model predicts that wind shear will be low, 5 - 10 knots, for the next five days. Ocean temperatures will warm from 27°C this morning to 28.5°C by Wednesday morning, and the total heat content of the ocean will increase sharply during that period, as well. The main impediment to development will be dry air to the north, and the SHIPS model predicts the amount of dry air will change little over the next five days. I expect that 94L will continue to struggle with dry air through Wednesday, when it will probably have had enough time to moisten the surrounding atmosphere and protect itself against the dry air. The models have shown increasing unity in taking 94L through the Lesser Antilles on Wednesday, and I expect the storm will be a tropical depression or weak tropical storm with 40 - 50 mph winds at that time. In their 8 am EDT Tropical Weather Outlook, NHC gave 94L a 80% chance of developing into a tropical depression by Wednesday morning. None of the reliable models predict that 94L will reach hurricane strength over the next five days, and it is unlikely that 94L will be able to organize quickly enough to become anything stronger than a 60 mph tropical storm before reaching the Lesser Antilles, given the storm's current struggles with dry air, and the lack of model support for intensification. However, once 94L enters the Eastern Caribbean, wind shear will be low, oceanic heat content high, and the storm should have had enough time to moisten the atmosphere to allow steady strengthening to occur. The main factor that might prevent intensification into a hurricane late this week would be a close pass by the island of Hispaniola. Our top models for long-range 4 - 5 days forecasts all show a path for 94L very close to the island.

Will 94L hit the U.S. mainland?
This storm is a long-range threat to the U.S., as historically, 16% of storms in 94L's location have gone on to hit the U.S., with North Carolina the preferred target (10% chance.) A trough of low pressure capable of pulling 94L to the north enters Western Canada Thursday night, and the exact timing and amplitude of this trough will determine the ultimate landfall location of 94L. The long range 7 - 14 day runs of the GFS model over the past three day have all predicted an eventual landfall for 94L in the U.S., though these long-range runs are notoriously unreliable. The predicted landfall locations have ranged from New England to Texas--which isn't much help. The past three runs beginning on Sunday afternoon have all taken 94L over Florida during the August 27 - 29 time frame, which I'm sure is making organizers of the Republican National Convention uncomfortable, since the convention is in Tampa August 27 - 30. However, 94L could miss Florida completely, as the average error in model forecasts going out 7 days is in excess of 500 miles. We can't rule out a North Carolina landfall, but the pattern we've seen so far this year is for landfalls in Mexico's Yucatan Peninsula, so a more southwards path for 94L into the Yucatan is definitely a possibility. Also, we have that huge drought region in the Midwest, which tends to create its own high pressure bubble, which reduces the odds of storms making the turn and hitting the Central or Western Gulf Coast. If 94L makes it to the Western Caribbean, I see the two most likely options as a landfall in Mexico's Yucatan Peninsula (and then westwards into Mexico south of the Texas border), or recurvature into the Florida Gulf Coast.


Figure 2. MODIS satellite image of Hurricane Gordon taken on Sunday August 19, 2012, at 11:55 am EDT. At the time, Gordon was a Category 2 hurricane with 100 mph winds. Image credit: NASA.

Gordon hits the Azores
The eye of Hurricane Gordon passed over Santa Maria Island in the eastern Azores Islands near 1:30 am EDT this morning. Gordon was a Category 1 hurricane with 75 - 80 mph winds at landfall. Winds at the Santa Maria airport reached a sustained 49 mph at 3 am EDT, but the airport did not report winds during passage of the eyewall at 1:30 am. Reuters reported that Gordon caused only minor flooding and power outages. The hurricane is being sheared apart by strong upper-level winds, and the extratropical remnants of Gordon will not bring any strong winds or significant rain to Europe.

Disturbance 95L in the Gulf near the Texas/Mexico border
A region of disturbed weather (Invest 95L) has developed in the Gulf of Mexico off the coast, just northeast of Tampico, Mexico. The disturbance is due to a trough of low pressure and its associated cold front which moved off the coast over the weekend, but has been fortified via moisture from Tropical Storm Helene, which made landfall Saturday near Tampico. If 95L were to develop into a tropical storm, it would receive a new name. In their 8 am EDT Tropical Weather Outlook, NHC gave 95L a 30% chance of developing into a tropical cyclone by Wednesday morning. An Air Force hurricane hunter aircraft is scheduled to investigate 95L this afternoon. Winds at Tampico this morning were light out of the northeast, which implies that no surface circulation is forming at this time. Radar out of Altamira, Mexico does show some banding to the precipitation echoes, though, which may be indicative of something trying to spin up. The computer models show that 95L should move little over the next few days.


Figure 3. Radar out of Altamira, Mexico at 9:45 am EDT August 20, 2012, shows some banding to the precipitation echoes in association with 95L.

Disturbance 96L off the coast of Africa
The tropical Atlantic is very busy this third week of August, and this is the week of the year that we typically see a major ramp-up of tropical storm activity in the Atlantic. A new tropical wave that emerged from the coast of Africa Sunday (Invest 96L) is headed west at 15 - 20 mph. This disturbance has a modest amount of spin and heavy thunderstorm activity, and is under a moderate 10 - 20 knots of wind shear. In their 8 am EDT Tropical Weather Outlook, NHC gave 96L a 20% chance of developing into a tropical cyclone by Wednesday morning. This disturbance does not have much model support for development.


Figure 4. The new Suomi National Polar-orbiting Partnership satellite (S-NPP) carries an instrument so sensitive to low light levels that it can detect wildfires in the middle of the night. On August 17, 2012, the Visible Infrared Imaging Radiometer Suite (VIIRS) on Suomi-NPP acquired this image of the wildfires blazing in Idaho. The images were created with data from the instrument’s "day-night band," which sensed the fire in the visible portion of the spectrum. The Halstead Fire, centered about 18 miles northwest of Stanley, was sparked by lightning on July 27, and is burning in an area with large numbers of trees killed by the mountain pine beetle. As of Sunday afternoon, the fire had burned 92,000 acres was only 5% contained, according to InciWeb. The fire prompted the evacuation of the town of Featherville on Saturday night. Red flag warnings for adverse fire weather were posted in the region yesterday, and temperatures reached the low 90s with 16% humidity and winds of 10 mph. Image credit: NASA.

A record fire season in the U.S.
Massive fires continue to burn in Nevada, Idaho and California, and fires that are currently active in the Western U.S. have consumed over 1.3 million acres of land--an area approximately the size of Delaware. Thanks to widespread drought and unusually high temperatures over the past month, 3 million acres have gone up in flames since mid-July, and the fire season of 2012 now ranks in first place for the most acreage burned at this point in the year. According to the Interagency Fire Center, 6.8 million acres have burned as of August 19 this year, beating the previous record set just last year (6.5 million acres for the year-to-date period.) The Interagency Fire Center shows year-to-date records just for the past ten years. The 2012 fire season is well ahead of the pace of 2006, which was the worst fire year in the U.S. for total acreage burned in a year (records began in 1960). In 2006, 9.9 million acres burned, and 6.4 million acres had burned by August 19. With drought conditions far more widespread this year compared to 2006, and the latest forecasts calling for little drought relief over the coming two months, 2012 is likely to surpass 2006 as the worst fire year in U.S. history before the end of the year.


Figure 5. Comparison of drought conditions between the previous record fire year in the contiguous U.S. (2006) with 2012. Drought is much more widespread in 2012 compared to 2006, and 2012 will likely finish ahead of 2006 for the most acreage burned since record keeping began in 1960. Image credit: U.S. Drought Monitor.

Global warming expected to increase fire activity in the Western U.S.
As I blogged about in June, the severe fire seasons of 2012 and 2011 fit the pattern of what we expect to see more of with global warming. Hotter heat waves dry out vegetation more readily, resulting in increased probability of more acreage burned. A study published in the Journal Ecosphere in June 2012 used fire models driven by the output from sixteen climate models used in the 2007 IPCC report and found that while 8% of the planet should see decreases in fire activity over the next 30 years, 38% should see increases. By the end of the century, 20% of the globe should see decreased fire activity, and 62% increased fire activity. In the U.S., the regions most at risk of increased fires are the tundra regions of northern Alaska, and the West, with Arizona and Colorado at particularly high risk.

Jeff Masters

hugh blanket of smoke (got2dogs)
blew in about an hr after my last upload here - I thought I was done for the nite, but this smoke was incredible! made for some awesome light - sooooo eerie!
hugh blanket of smoke
Smoke! What smoke ?? (saltydawgg)
12th Ave road South looking north. Nampa Idaho full of smoke from 7 fires at last count with more dry lightning on the way.
Smoke! What smoke ??
Temecula Fire (photoandy)
This is just two hours after ignition! It quickly became a PYROCUMULUS...
Temecula Fire

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Quoting sunlinepr:


LLCOC is right under the most intense convection. Should see Issac by 11am. Also the is nothing compare to the size it could get down the road
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Quoting Hurricanes305:


Naw not really it should weaken some


Hope you are correct.... For sure this is not Ernesto...
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Quoting Thewatchcontinues:
looks like i might have been right all along it looks like our td storm will go passed florida to the south


If it becomes close to the strength the NHC has it should have a right turn to the NW-NNW. If its much weaker a WNW track over Cuba into the gulf.
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3177. LargoFl
first warning going up.....WTNT64 KNHC 210910
TCUAT4

TROPICAL DEPRESSION NINE TROPICAL CYCLONE UPDATE
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092012
510 AM AST TUE AUG 21 2012


...TROPICAL STORM WARNING ISSUED FOR ANGUILLA...

THE GOVERNMENT OF ANTIGUA HAS ISSUED A TROPICAL STORM WARNING FOR
ANGUILLA.

$$
FORECASTER STEWART
Member Since: August 6, 2011 Posts: 4 Comments: 36615
Closed core was consolidated...

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Quoting sunlinepr:
Ugly situation for us... That low N of PR, extracting the Dry air to the N, could influence Isaac to the NW.... that will put the storm over PR....





Naw not really it should weaken some
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These intensity forecasts will be updated today...

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Ugly situation for us... That low N of PR, extracting the Dry air to the N, could influence Isaac to the NW.... that will put the storm over PR....



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Caribbean

AN AREA OF 1007 MB LOW PRES IS E OF THE TROPICAL N ATLC NEAR
15N50.5W WITH A TROPICAL WAVE EXTENDING NORTHWARD FROM THE LOW
CENTER TO 21N47W. CONVECTION IS INCREASING NEAR THIS LOW AND IT
HAS A VERY HIGH PROBABILITY OF TROPICAL CYCLONE DEVELOPMENT AND
IT COULD BECOME A TROPICAL DEPRESSION LATER TODAY. 20-30 KT
WINDS ARE ALREADY OCCURRING IN THE NE SEMICIRCLE OF THE LOW WITH
A TIGHT PRES GRADIENT IN PLACE BETWEEN THE LOW/TROPICAL WAVE AND
HIGH PRES TO THE NW. THIS LOW IS FORECAST TO IMPACT THE E
CARIBBEAN WATERS BY EARLY WED AND INTO THE E CARIBBEAN LATE WED
AND THU...THEN CENTRAL CARIBBEAN FRI.

INTERESTS IN THE CARIBBEAN SHOULD CONTINUE TO MONITOR ANY
DEVELOPMENTS OF THIS LOW THROUGH THE WEEK INTO THE WEEKEND.

Atlantic


WINDS WILL INCREASE AND
SEAS WILL BUILD BEGINNING IN AMZ125 LATER TODAY...SPREADING W-NW
AS A DEVELOPING AREA OF 1007 MB LOW PRES CURRENTLY NEAR 15N50.5W
MOVES CLOSER TO THE SOUTHERN WATERS. THIS FEATURE HAS A VERY
HIGH PROBABILITY OF TROPICAL CYCLONE DEVELOPMENT AND IT COULD
BECOME A TROPICAL DEPRESSION LATER TODAY. THE LOW IS EXPECTED TO
IMPACT THE NE CARIBBEAN BY LATE WED...THEN POTENTIALLY THE
GREATER ANTILLES BY THE END OF THE WEEK. REGARDLESS OF THE EXACT
TRACK...A TIGHT PRES GRADIENT WILL REMAIN OVER THE SOUTHERN
WATERS BETWEEN THE HIGH...WHICH WILL BE RETREATING NORTHWARD...
AND THE LOW.

INTERESTS FROM THE NE CARIBBEAN TO ACROSS THE GREATER
ANTILLES...TURKS AND CAICOS...AND THE BAHAMAS SHOULD CONTINUE TO
MONITOR ANY DEVELOPMENTS OF THIS LOW THROUGH THE WEEK INTO THE
WEEKEND.
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3168. SLU
Quoting SLU:
Maybe I just need some coffee but earlier morning visible imagery shows that the center could be further south of the NHC position near 14.8n 52w and that TD 9 could be much stronger than 35mph and starting to undergo some RI.



This could also be a logical explanation as to why the winds at the buoy just ahead of the system have not backed towards the west yet but instead have veered back to the north-northeast.
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3167. LargoFl
Man we had one Powerful storm blow thru here last night,lightning and wind like you would not believe..I lost power for over a half hour, just around 9 15 or so....Big Boomers, tons of rain etc...did damage in clearwater etc
Member Since: August 6, 2011 Posts: 4 Comments: 36615
Quoting LargoFl:
yesterday it was 3.59 a gallon
omg dats horrible! if dat storm comes that way its gonna be hell! make sure u fill up largo
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early.morning.vis.can.be.misleading..strenghtening. for.sure
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Where to start...

MARINE WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
257 AM EDT TUE AUG 21 2012

MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA
AND TROPICAL N ATLC...AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W.

GULF

A SEPARATE SURFACE TROUGH IS JUST E OF THE MEXICAN COAST
FROM NEAR 24N97W TO 19N96W. THIS FEATURE IS FORECAST TO LINGER
OVER THE SAME GENERAL AREA THROUGH THU...MOVING INLAND OVER
MEXICO FINALLY BY THE END OF THE WEEK AS THE HIGH MENTIONED
ABOVE PUSHES IN FROM THE NE. THIS TROUGH HAS A MEDIUM
PROBABILITY OF TROPICAL CYCLONE DEVELOPMENT DURING THE NEXT 48
HOURS. ALSO...A TROPICAL WAVE CURRENTLY IN THE NW CARIBBEAN MAY
CLIP THE SW GULF AND MERGE WITH THIS TROUGH LATER THIS WEEK.


THE HIGH WILL RETREAT TO THE NE FRI AND SAT POTENTIALLY ALLOWING
FOR AN AREA OF LOW PRES AND ATTENDANT TROPICAL WAVE CURRENTLY E
OF THE CARIBBEAN ISLANDS TO MOVE TOWARD THE SE GULF. THIS LOW
HAS A HIGH PROBABILITY OF BECOMING A TROPICAL CYCLONE DURING THE
NEXT 48 HOURS. IF THIS SCENARIO OCCURS...EXPECT DETERIORATING
CONDITIONS (INCREASING WINDS AND SEAS) IN THE SE GULF LATE SAT
INTO SUN.
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3162. LargoFl
Quoting bigwes6844:
speaking of gasoline. how high is gas in florida by u?
yesterday it was 3.59 a gallon
Member Since: August 6, 2011 Posts: 4 Comments: 36615
3161. SLU
Maybe I just need some coffee but earlier morning visible imagery shows that the center could be further south of the NHC position near 14.8n 52w and that TD 9 could be much stronger than 35mph and starting to undergo some RI.

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Quoting LargoFl:
Gasoline for a hurricane alright and the sun isnt up yet and already high 80's............
speaking of gasoline. how high is gas in florida by u?
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3159. LargoFl
Member Since: August 6, 2011 Posts: 4 Comments: 36615
big.ones.dont.like.the.big.bend.area..more.west.or. south
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3157. LargoFl
Gasoline for a hurricane alright and the sun isnt up yet and already high 80's............
Member Since: August 6, 2011 Posts: 4 Comments: 36615
Thanks Tom. Your explaination was wonderful. I'll just sit back and watch.
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Quoting AussieStorm:

Thanks, I was more wondering what intensity they had it at. but that looks like a East GOM/W Fla. hit. Worse case scenario is Isaac goes right up the west coast of Florida then follows the same path Debby took as she went NE.


Yeah and that looked like the way it was headed on the EURO.
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3154. LargoFl
Quoting clwstmchasr:


Kinda reminds of Charlie right now.
..sure does, one good thing..so far, no track has it going into say..miami, then traveling across florida, then out tampa bay...thats the WORST track we can have..for us in pinellas..that pushes the whole bay..towards us
Member Since: August 6, 2011 Posts: 4 Comments: 36615
Quoting islander101010:
right.in.the.middle.of.that.narrow.cone..cuba.won t. slow.it.much


Yeah, just depends where/how if it were to hit Cuba. Going along the length and over the mountainous area would likely cause a lot of weakening. But could easily go right across or the COC stay offshore. So many variables.

I agree with Athome and Bigwes, 95L is really a pressing concern being so much closer and just sitting there trying to strengthen!
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Quoting AtHomeInTX:


Probably something like this. They said they coordinated with NHC.


Thanks, I was more wondering what intensity they had it at. but that looks like a East GOM/W Fla. hit. Worse case scenario is Isaac goes right up the west coast of Florida then follows the same path Debby took as she went NE.
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There's a lot to look at on the 00z ECMWF Ensembles. The consensus seems to be centered around Florida in 7 or 8 days. But again, a lot will depend on the storms intensity when it reaches the weakness in the ridge. At 192 hrs, the weakness is clear. But if the storm stays weaker prior to this it will head further west and end up in the Gulf where it will have time to fester...For example, if we look at the 168 hrs MSLP ECMWF Ensembles we see most of the Ensemble members are around Cuba heading towards the vicinity of Florida. However, when we look at 240 hrs we see plenty of purple showing up across the Gulf indicating some members are keeping the system in the Gulf and allowing Isaac to intensify.

For now, models seem to be in fairly good agreement on track for the next 5 days. The real challenge is beyond 5 days when the storm will begin to turn in response to the weakness. Just how much it will turn will depend greatly on the strength of the system. Unfortunately, our models are very poor at long range intensity forecasts, so we are seeing highly divergent model solutions beyond 7 days. People from New Orleans to Cape Hatteras should be prepared.



Quoting Levi32:


It's the fact that he's stronger, but simultaneously farther south, that bothers me. Stronger should mean farther north in this situation. It will be an interesting storm to track, for sure.

I must get my 4 and 1/2 hours of sleep now before I get to work on my update for later this morning. Night all.
Exactly.

I'm out for the night too, later y'all
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x
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Quoting AussieStorm:
I wonder what the NHC in house 7 day track looks like. That would be interesting.


Probably something like this. They said they coordinated with NHC.

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3146. LargoFl
Quoting clwstmchasr:


The big question for us here in the Tampa area is does it ride up the West or East coast of FL. The RNC must have gone into alert mode about a half an hour ago.
yes this could be very dangerous..if..it goes up the east coast, we on the west side should be ok, if it goes up the spine of florida we got trouble..if it goes UP the west coast of florida we got trouble ..if it goes thru lower south florida and into the middle of the gulf..Tampa area should be ok...so which way does it go..nobody knows for sure yet
Member Since: August 6, 2011 Posts: 4 Comments: 36615
Quoting LargoFl:
......funny thing is..my local mets say this could be a cat 2...even Before it gets into the gulf


That's the view of the NHC in their intensity forecast...a strengthening Category 2 hurricane approaching Cuba in the 5 day time period. I admit that even for Stewart who likes to produce more aggressive intensity forecasts, I was surprised to see him go much higher than the global model consensus and more in line with SHIPS.
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3143. LargoFl
......funny thing is..my local mets say this could be a cat 2...even Before it gets into the gulf
Member Since: August 6, 2011 Posts: 4 Comments: 36615
Thanks for your response Largo! :)
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Quoting LargoFl:
27th thru the 30th
Aww man thats horrible! Maybe Dr masters could be right about the chances of a storm interrupting the RNC
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I wonder what the NHC in house 7 day track looks like. That would be interesting.
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3138. LargoFl
Quoting Sunbeam81:
Are the tracks still kind of all over the place? I live in SC and to be honest I'm a little worried. I remember Hugo. It was very scary. I was only 8 at the time but now i have children of my own and I'm a bit worried for them going through a hurricane. :)
yes NOT set in stone yet, east and west needs to watch this one closely..looks right now like it could go either way, my hunch is..into the gulf
Member Since: August 6, 2011 Posts: 4 Comments: 36615
Quoting AtHomeInTX:


Yeah, I don't think it's right. lol But I still watch.
I hope so because anything in the GOM will be worth watching especially with those warm temps!
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Are the tracks still kind of all over the place? I live in SC and to be honest I'm a little worried. I remember Hugo. It was very scary. I was only 8 at the time but now i have children of my own and I'm a bit worried for them going through a hurricane. :)
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3135. LargoFl
Quoting bigwes6844:
when is the convention?
27th thru the 30th
Member Since: August 6, 2011 Posts: 4 Comments: 36615
3134. Levi32
Quoting TomTaylor:
Evening/morning night shift. See we got TD9, not sure I really like the Stewart's intensity forecast, just comparing his forecast to the global models. Also interesting how he takes the storm further south than most of the model guidance while intensifying it more than the global models predict.


It's the fact that he's stronger, but simultaneously farther south, that bothers me. Stronger should mean farther north in this situation. It will be an interesting storm to track, for sure.

I must get my 4 and 1/2 hours of sleep now before I get to work on my update for later this morning. Night all.
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3133. LargoFl
0
WTNT44 KNHC 210858
TCDAT4

TROPICAL DEPRESSION NINE DISCUSSION NUMBER 1
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092012
500 AM AST TUE AUG 21 2012

THE LARGE LOW PRESSURE SYSTEM THAT HAS BEEN TRAVERSING THE CENTRAL
TROPICAL ATLANTIC FOR THE PAST FEW DAYS HAS ACQUIRED ENOUGH
ORGANIZED DEEP CONVECTION NEAR THE CENTER TO BE CLASSIFIED AS A
TROPICAL DEPRESSION. THE INITIAL INTENSITY OF 30 KT IS BASED ON A
SATELLITE INTENSITY ESTIMATE OF T2.0/30 KT FROM TAFB AND T1.5/25 KT
FROM SAB. SINCE THE 0600 UTC SATELLITE CLASSIFICATIONS...
CONVECTION HAS CONTINUED TO INCREASE WITH SOME CLOUD TOP
TEMPERATURES COLDER THAN -80C NOTED JUST SOUTHWEST OF THE LOW-LEVEL
CENTER.

THE INITIAL MOTION ESTIMATE IS 270/17 KT. THE DEPRESSION IS LOCATED
SOUTH OF A DEEP-LAYER SUBTROPICAL RIDGE THAT IS FORECAST TO REMAIN
INTACT FOR THE NEXT FOUR DAYS...WHICH SHOULD KEEP THE CYCLONE
MOVING IN A WESTWARD TO WEST-NORTHWESTWARD DIRECTION THROUGH 96
HOURS. BY DAY 5...HOWEVER...THE GLOBAL MODELS ARE FORECASTING A
SHORTWAVE TROUGH TO DIG SOUTHWARD OVER THE SOUTHEASTERN U.S. AND
THE GULF OF MEXICO...WHICH IS EXPECTED TO WEAKEN THE RIDGE ACROSS
FLORIDA AND THE BAHAMAS. THIS SHOULD ALLOW THE CYCLONE TO TURN
NORTHWESTWARD AND SLOW DOWN ACROSS THE NORTH-CENTRAL CARIBBEAN SEA.
THE OFFICIAL FORECAST TRACK IS CLOSE TO THE MULTI-MODEL CONSENSUS
TVCA...WHICH IS A COMPROMISE OF THE FASTER GFS MODEL AND SLOWER
ECMWF MODEL.

OTHER THAN SOME MODEST NORTHEASTERLY VERTICAL WIND SHEAR FOR THE
NEXT 24 HOURS OR SO...ENVIRONMENTAL CONDITIONS ARE EXPECTED TO BE
QUITE FAVORABLE FOR INTENSIFICATION TO OCCUR. DURING DAYS 2-3...THE
VERTICAL SHEAR IS FORECAST TO BE THE WEAKEST AND WATER TEMPERATURES
THE WARMEST...AND THAT IS WHEN THE MOST SIGNIFICANT STRENGTHENING
SHOULD OCCUR. AT DAYS 4 AND 5...POSSIBLE INTERACTION WITH LAND
MASSES OF HAITI AND CUBA...RESPECTIVELY...IS THE PRIMARY REASON
FOR THE LEVELING OFF IN THE INTENSITY. THE OFFICIAL INTENSITY
FORECAST CLOSELY FOLLOWS THE TREND OF...BUT IS LOWER THAN...THE
SHIPS AND LGEM INTENSITY MODELS...ESPECIALLY AT DAYS 3 AND 4.

AN AIR FORCE RESERVE RECONNAISSANCE AIRCRAFT WILL INVESTIGATE THE
CYCLONE THIS AFTERNOON.

FORECAST POSITIONS AND MAX WINDS

INIT 21/0900Z 15.2N 51.2W 30 KT 35 MPH
12H 21/1800Z 15.3N 53.8W 35 KT 40 MPH
24H 22/0600Z 15.7N 57.2W 40 KT 45 MPH
36H 22/1800Z 16.0N 60.5W 50 KT 60 MPH
48H 23/0600Z 16.3N 63.6W 65 KT 75 MPH
72H 24/0600Z 16.9N 69.3W 80 KT 90 MPH
96H 25/0600Z 18.0N 74.0W 95 KT 110 MPH
120H 26/0600Z 20.0N 77.3W 95 KT 110 MPH

$$
FORECASTER STEWART


Member Since: August 6, 2011 Posts: 4 Comments: 36615
Quoting LargoFl:
yep..looks like we will be getting hit..so far at least
when is the convention?
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Quoting Levi32:


The ECMWF has the best solution of any global model. Sometimes I think that can be a detriment, if that is actually possible. Too much feedback of small-scale wavelets within the circulation that cause the model to choke, perhaps.


That's a great point actually. I do think it is the quickest model to pick up on small and shallow features and mesoscale influences and thus we usually see problems when a synoptic scale system hasn't consolidated yet.
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About

Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.