Alex continues to slowly organize

By: Dr. Jeff Masters , 7:17 PM GMT on June 28, 2010

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Tropical Storm Alex continues to slowly grow more organized as it steams away from Mexico's Yucatan Peninsula. Satellite loops show that Alex's heavy thunderstorms continue to increase in areal extent, and low level spirals bands are slowly building to the south and north. The clockwise flow around an upper-level high pressure system a few hundred miles west of Alex is bringing about 15 knots of wind shear to the storm, which is slowing intensification. Heavy thunderstorm activity is limited on the storm's northwest side, thanks to the shear and some dry continental air flowing off the coast of North America. Sea Surface Temperatures are very warm, 29°C. The latest Hurricane Hunter center fix, at 12:07 pm CDT, showed a central pressures of 990 mb, a 1 mb rise in six hours. Top winds were holding steady near 60 mph. Alex has stalled out the last few hours, as it began to "feel" the trough of low pressure to its north breaking down the high pressure ridge that has been pushing the storm to the west-northwest. This stall has allowed the storm to churn up cold water from the depths, which is probably interfering with development. Satellite loops show that Alex has a very large circulation covering about 2/3 of the Gulf of Mexico. We can expect that should Alex become a Category 2 or stronger hurricane, its storm surge will affect a much wider stretch of coast than Hurricane Dolly of 2008 did.


Figure 1. Afternoon satellite image of Alex.

Track forecast for Alex
The latest 12 UTC (7am CDT) runs of our most reliable computer models have come into much better agreement. A consensus forecast arrived at by averaging together most or all of the tracks of our top models--the GFS, ECMWF, GFDL, NOGAPS, HWRF, UKMET, and GFDN--is pretty much what NHC always uses as the basis of their forecast. This consensus forecast has narrowed in on the region just south of the Texas/Mexico border as being the most likely landfall location, with the usual cone of uncertainty surrounding it. The computer model that had been making the northernmost landfall predictions, the Canadian model, is now projecting a landfall 100 miles south of the Texas/Mexico border. There has been a general southward shift of the models in their latest runs, and the most northerly landfall location, near Port Mansfield, is now being predicted by the HWRF model. The earliest landfall time is Wednesday morning, and the latest is Thursday morning. Which model should you trust? Last year, the best performing models at the 3 day forecast period were the GFS, Canadian, ECMWF, and GFDL.

With steering currents relatively weak, the uncertainty in landfall location is high. The average error in an NHC 72-hour track forecast last year was 230 miles, which is about the distance from Brownsville to Port O'Connor. Consider also that the NHC cone of uncertainty is the region where 2/3 of the time (using the last 5 years of statistics) the center of a storm will go. Forecast errors tend to be equally large along track (speed errors) and cross-track (deviations from side-to-side), so that means that about 20% of the time a storm will not be in the cone of uncertainty. Given the slow motion of Alex and the recent uncertainty of the computer models, people living just beyond the edge of the cone of uncertainty should not be confident yet that Alex will miss them.

To get the probability of receiving tropical storm force winds or hurricane force winds for your location, I recommend the NHC wind probability forecasts. The 10am CDT (15 UTC) wind probability product predicted that Brownsville, Texas had the highest odds of getting a direct hit from Alex:

Brownsville, TX: 67% chance of tropical storm conditions (winds 39+ mph), 16% chance of hurricane force winds (74+ mph). This is the cumulative probability through Saturday morning. The wind probability forecasts also include separate probabilities for each 12-hour period between now and three days from now, and each 24 hours for the period 4 - 5 days from now.

La Pesco, MX: 49% tropical storm, 6% hurricane.

Tampico, MX: 31% tropical storm, 4% hurricane.

Corpus Christi, TX: 45% tropical storm, 6% hurricane.

Freeport, TX: 23% tropical storm, 2% hurricane.

Galveston, TX: 21% tropical storm, 1% hurricane.


Figure 2. Skill of computer model forecasts of Atlantic named storms during 2009. OFCL=Official NHC forecast; GFS=Global Forecast System model; GFDL=Geophysical Fluid Dynamic Laboratory model; HWRF=Hurricane Weather Research Forecasting model; NOGAPS=Navy Operational Global Prediction System model; UKMET+United Kingdom Met Office model; ECMWF=European Center for Medium Range Weather Forecasting model; CMC=Canadian GEM model; TVCN=one of the consensus models that lends together all (or most) of the above models; BAMM=Beta and Advection Model (Medium Layer.) Image credit: National Hurricane Center 2009 verification report.

Uncertainty in the NHC Cone of Uncertainty
A research project funded by NOAA known as the Joint Hurricane Testbed has produced a remarkable number of tools now in operational use at the National Hurricane Center to improve hurricane forecasts and warnings. One of these projects, called "Prediction of Consensus TC Track Forecast Error and Correctors to Improve Consensus TC Track Forecasts", was an effort by Dr. Jim Goerss at the Navy Research Lab to improve the accuracy of the NHC "cone of uncertainty" (AKA the "Cone of Death") showing where a storm is expected to track 2/3 of the time. The radius of the circles that make up the cone are based on error statistics of the official NHC forecast over the past five years. We can expect in certain situations, such as when the models are in substantial disagreement, a consensus forecast made using these models will have much greater than average errors. Since the NHC typically bases their forecast on a consensus forecast made using a combination of reliable hurricane forecasting models, it is instructive to view the "GPCE" (Goerss Prediction Consensus Error) circles to see if the uncertainty cone should be smaller or larger than usual. The consensus forecast I'll look at is called "TVCN", and is constructed by averaging the track forecasts made by most of (or all) of these models: GFS, ECMWF, NOGAPS, GFDL, HWRF, GFDN, and UKMET. In the case of this morning's 12 UTC (7am CDT) June 28 run of these models, here is what the radius of the "cone of uncertainty" should be, in nautical miles:

12 hours: 42 nm
24 hours: 73 nm
36 hours: 96 nm
48 hours: 112 nm
72 hours: 173 nm
96 hours: 327 nm
120 hours: 376 nm

And here is the radius of NHC's "cone of uncertainty" for their official forecast, based on the average errors for the past five years:

12 hours: 36 nm
24 hours: 62 nm
36 hours: 85 nm
48 hours: 108 nm
72 hours: 161 nm
96 hours: 220 nm
120 hours: 285 nm

So, the GPCE error estimates are showing that the latest forecasts for Alex out to 72 hours are 4% - 17% higher in uncertainty than average. The 4 - 5 day forecasts are 32% - 49% more uncertain than average--but of course, we expect Alex to be inland at those times.

Intensity forecast for Alex
Alex is currently over a region of ocean with relatively low total ocean heat content (about 10 - 30 kJ/cm^2). By Tuesday and Wednesday, the heat content will increase to 40 - 70 kJ/cm^2, which is high enough to allow Alex to rapidly intensify. Wind shear is currently a moderate 15 knots, and is projected by the SHIPS model to decrease to the low range, below 10 knots, on Tuesday and Wednesday. The combination of low wind shear and high ocean heat content should allow Alex to intensify into a hurricane. NHC is giving Alex a 78% chance of being a hurricane on Wednesday morning, and a 16% chance it will be a major hurricane at that time. Water vapor satellite images, though, show plenty of dry air over Texas and the adjoining waters, and this dry air may turn out to be a significant detriment to Alex. Another factor limiting Alex's intensification may be that the atmosphere is more stable than usual right now--temperatures at 200 mb are a rather warm -50°C, and are expected to warm an additional 1 - 2 degrees by Wednesday. Another factor limiting Alex's intensification may be its slow forward speed. Alex has already stalled out once, and may stall out later in its path, as well. A stalled-out storm tends to pull up cold water from the depths, limiting intensification. In short, Alex has the potential to intensify into a major hurricane, but there are enough roadblocks that I give a 20% chance of this happening.

Elsewhere in the tropics
None of the reliable computers models is calling for tropical storm formation over the the next seven days in the Atlantic.

Wind and ocean current forecast for the BP oil disaster
It currently appears that Alex will not directly affect the oil slick location, other than to bring 2 - 4 foot swells to the region on Wednesday. However, because Alex is such a deep low pressure region, strong southeast winds of 15 - 25 knots will blow over the oil slick region today through Wednesday, according to the latest marine forecast from NOAA. The resulting currents should act to push oil to the west and northwest onto portions of the Louisiana, Mississippi, and Alabama coasts, according to the latest trajectory forecasts from NOAA and the State of Louisiana. Oil will also move westward along the central Louisiana coast towards the Texas border.

Resources for the BP oil disaster
Map of oil spill location from the NOAA Satellite Services Division
My post, What a hurricane would do the Deepwater Horizon oil spill
My post on the Southwest Florida "Forbidden Zone" where surface oil will rarely go
My post on what oil might do to a hurricane
NOAA's interactive mapping tool to overlay wind and ocean current forecasts, oil locations, etc.
Gulf Oil Blog from the UGA Department of Marine Sciences
Oil Spill Academic Task Force
University of South Florida Ocean Circulation Group oil spill forecasts
ROFFS Deepwater Horizon page
Synthetic Aperture Radar (SAR) imagery from the University of Miami

Portlight continues its Haiti response
Hurricane season is here, and Haiti is not ready. Over 1.5 million Haitians are living outside in tents or under tarps, and are highly vulnerable to a hurricane. Portlight is working on constructing steel shelters out of shipping containers for homeless Haitians, as detailed in the Haitian Relief Recap blog post. Please visit the Portlight.org web site or the Portlight blog to learn more and to donate to Portlight's efforts in Haiti.


Figure 3. Still frame from the remarkable video taken inside the Haitian Presidential Palace during the 2010 earthquake.

To remind people of just how devastating the earthquake was, the Haitian government released a video earlier this month showing the inside of the Haitian Presidential Palace during the mighty Haitian earthquake.

Next post
Dr. Rob Carver is planning on making a post late tonight, and I'll have an update by 9:30am CDT on Tuesday.

Jeff Masters

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Quoting sarahjola:

i agree. to the one who wants stats with comments- this is an opinion blog. even the experts are just guessing and so far have been kinda wrong. not one met. or expert has said that this would stall out for so long. usually when a storm stalls its cuz its changing direction or relocating coc. Alex is not all the powerful yet. its just big. its still a tropical storm, not a hurricane. coc's have relocated before in tropical storms and hurricanes. nothing is impossible.


I'm speaking to the issue of assertions without reasoning behind them like "it's going to ……." or "Some one said." I'm not looking for footnote quality referencing but a little more verifiability than a lot of posts. Yes it is an opinion based forum but a degree of responsibility for verifiable referencing and a reasoned response advances the learning of folks like me. All opinions are not of equal value. There are reasoned informed opinions and then their's the guy on the square ranting about the black copters coming.
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Best example..

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That pop-corning that happened when Alex got off land yesterday is starting up again, inflow should begin spiraling tightly into the center to allow for Convection fireup and vertical stacking once more.
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Quoting TampaSpin:
The High Pressure Ridge is breaking down pretty fast to the North now....NICE LOOP TO SEE

Also look at the ULL developing in Arizona...HUM


It's fluctuating, so what? Canes do it all the time. It's Mexico, or S. Texas.
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Quoting RitaEvac:
NHC gonna pull their hair out when it goes towards Mexico and then the next trough comes down it Alex goes back north


Yep and you can see it coming on the loop i just posted....NOT SAYING it will but landfall could end up in the Panhandle of Florida if the timing of the Front is just right....wouldn't that be something.
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Quoting HurricaneSwirl:
Visible Floater: Link

Last frame of Alex actually looks a lot better than the first frame of Alex if you'll notice. I actually do kinda see an east wobble, but then I followed the COC with my mouse pointer and I think the east part is just an illusion.


I try not to trust anything I "see" in the last frame of a loop. I always "see" what looks like a jump left or right of forward, and it almost never pans out into anything.
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Quoting MiamiHurricanes09:
Could be a wobble but not true motion.


It's either a VERY slight wobble or some sort of illusion.
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Handy link for models if anybody needs one : Link

Somebody posted it here a year or two ago, but not sure who the credit goes to.
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447. Daveg

I may be new, but I know one thing.

I think as many times as these models have bounced around that I wouldn't rule out a just north of the Texas border landfall quite yet.

I have to admit, this is all extremely interesting, and it's nice to see everyone's data and opinions here.
Member Since: September 23, 2005 Posts: 0 Comments: 426
Quoting oddspeed:
anyone think a new coc is forming about 100 miles north of present coc?


Circulation is way too defined. 990 mb COCs dont just relocate.. that's what happens with invests. If Alex starts falling apart (which it is starting to do the opposite of) then yeah I could see that.
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Quoting victoriahurricane:
Ok, how does one post links here? I obviously failed in my attempt.


http://wiki.wunderground.com/index.php/WunderBlogs_-_Adding_links_(URLs)

Member Since: July 24, 2006 Posts: 1 Comments: 987
My apologies if this has already been posted...

... I thought this was interesting. I don't know much about it, but from what I've heard, his record is pretty good.

Link

British weather forecaster says Alex will move much further north and east...

Piers Corbyn reveals revolutionary forecast concepts. WeatherAction long-range forecasts are produced using Piers Corbyn's Solar Weather Technique which is the most advanced and reliable long-range forecasting system in the world.

The technique uses predictable aspects of solar activity - particle and magnetic effects from the Sun - as the basis for forecasting weather many months and even years in advance. The essence of the technique is explained in scientific presentations (see News Archive).
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Link
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Quoting Jeff9641:


The latest vis I saw appears to have a NNE jog.
Could be a wobble but not true motion.
Member Since: September 2, 2009 Posts: 130 Comments: 21194
Quoting oddspeed:
anyone think a new coc is forming about 100 miles north of present coc?


That was a rumor earlier.

But I almost got decapitated for it.

LOL
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Quoting StSimonsIslandGAGuy:


The NHC mentioned it in the advisory:

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 70 MILES...110 KM
FROM THE CENTER. AN AUTOMATED STATION FROM THE MEXICAN NAVY AT CAYO
ARCAS RECENTLY REPORTED A SUSTAINED WIND OF 33 MPH...53 KM/HR...AND
A GUST OF 40 MPH...65 KM/HR.




Ohh and here I thought I had caught something missed.
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Visible Floater: Link

Last frame of Alex actually looks a lot better than the first frame of Alex if you'll notice. I actually do kinda see an east wobble, but then I followed the COC with my mouse pointer and I think the east part is just an illusion.
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Well Good Afternoon and Early Evening All,
I had to take a break from this thing call "Alex".....
So what have I missed other than it moved what about 35 to 40 miles to the NNW/NE maybe????

Taco :o)
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Quoting victoriahurricane:


Wunderground has it at a Cat 2 before landfall.

http://www.wunderground.com/tropical/tracking/at201001.html
Well the Wunderground site is incorrect. This is from the discussion:

INITIAL 28/2100Z 20.5N 91.8W 50 KT
12HR VT 29/0600Z 21.5N 92.4W 60 KT
24HR VT 29/1800Z 22.9N 93.7W 65 KT
36HR VT 30/0600Z 23.8N 95.1W 75 KT
48HR VT 30/1800Z 24.5N 96.4W 80 KT
72HR VT 01/1800Z 25.5N 99.5W 60 KT...INLAND
96HR VT 02/1800Z 26.0N 101.0W 25 KT...INLAND
120HR VT 03/1800Z...DISSIPATED

The maximum winds are 80 knots, that translates to 92mph which is then rounded down to 90mph. No Cat. 2 there.
Member Since: September 2, 2009 Posts: 130 Comments: 21194




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Quoting Jeff9641:
I say NE at 3 right now but this could be wobble. Interesting to see this. I thought this morning the center may want to move closer to all the convection N and NE.
Hey Everyone. Just popping in between loads of clothes UGH! Just an amateur observer but checked the latest still and looks like NE a lil' to me and the way it's shaped ?????
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anyone think a new coc is forming about 100 miles north of present coc?
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The High Pressure Ridge is breaking down pretty fast to the North now....NICE LOOP TO SEE

Also look at the ULL developing in Arizona...HUM
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Not sure this really matters at this point, but I noticed the barometric pressure is now dropping along the S. TX Gulf Coast. I'm in Rockport, working in Corpus and noticed it's falling from Brownsville up to Port Lavaca.
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Quoting StormW:


I don't know if the G4 has taken off yet, Levi...but I agree with you on track...I have some reservations about that ridge building...not that it won't, but my gut feeling, looking at the way the evolution of it is taking shape, could allow for a temporary move back to the NW or WNW, before another approaching trof. See what you think:



I don't have weathertap so the image isn't showing.

See post 407...dropsondes are being dropped everywhere.

I'm not completely sold on Mexico myself....I have a concern area up to Rockport, Texas. If Alex hits 25N 95W, it's probably going into Texas.
Member Since: November 24, 2005 Posts: 635 Comments: 26654
For tomorrow

The HH POD

Plan of the Day

000
NOUS42 KNHC 281430
WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
1030 AM EDT MON 28 JUNE 2010
SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)
VALID 29/1100Z TO 30/1100Z JUNE 2010
TCPOD NUMBER.....10-028

I. ATLANTIC REQUIREMENTS
1. TROPICAL STORM ALEX
FLIGHT ONE - NOAA 49
A. 30/0000Z
B. NOAA9 0901A ALEX
C. 29/1730Z
D. NA
E. NA
F. 41,000 TO 45,000 FT

FLIGHT TWO - TEAL 70
A. 30/0000,0300,0600Z
B. AFXXX 1001A ALEX
C. 29/2200Z
D. 23.5N 94.2W
E. 29/2330Z TO 30/0600Z
F. SFC TO 10,000 FT

FLIGHT THREE - TEAL 71
A. 30/0900,1200,1500Z
B. AFXXX 1101A ALEX
C. 30/0700Z
D. 24.1N 95.3W
E. 30/0830Z TO 30/1500Z
F. SFC TO 10,000 FT

2. SUCCEEDING DAY OUTLOOK: CONTINUE 3-HRLY FIXES.
POSSIBLE G-IV MISSION FOR 01/0000Z.

3. REMARKS: NOAA 42 WILL BE DOING RESEARCH FLIGHTS INTO
ALEX WITH TAKEOFFS EVERY 12 HRS FOR THE NEXT TWO DAYS.
(29/0800Z, 29/2000Z THROUGH 30/0800Z) OPERATING
ALTITUDE 12,000 FT.

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Surprised nobody noticed this pressure fall on the Cayos Arcas Islands, not to far from the COC of Alex.

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Quoting Jeff9641:


It looks like NE to me as well. It appears to want to get under that convection pulling off the Yucatan. I am glad someone else is seeing this. Some think NW and I say no way.

No it's not NE but obviously it is not a true NNW either. Still stalled. Plain and simple.
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NHC gonna pull their hair out when it goes towards Mexico and then the next trough comes down it Alex goes back north
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Latest Video Blog...Link
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Any thing being said about the ULL off the Bahamas? Can it work down to the surface? Is there a possiblity? What are your thoughts?
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Looks like the Hurricane Hunters are en-route now.
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Quoting StormW:


I don't know if the G4 has taken off yet, Levi...but I agree with you on track...I have some reservations about that ridge building...not that it won't, but my gut feeling, looking at the way the evolution of it is taking shape, could allow for a temporary move back to the NW or WNW, before another approaching trof. See what you think:



StormW, the ridge is firm....
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Quoting victoriahurricane:


Wunderground has it at a Cat 2 before landfall.

http://www.wunderground.com/tropical/tracking/at201001.html


They haven't updated the track yet, they updated the time and stats but not the track for some reason. You can tell because the track is too far north, it shows a cat 2 (if you look in the 5PM discussion for Alex it shows the max winds being 80 knots which is a high end cat 1), and because the dots are labeled with 8 PM and AM. At the 5 PM advisory, the dots should be labeled 2PM and AM I think.
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finally getting some much needed rain in south jersey, I can go a day with hand watering the garden, whahoo! hey plus a light show too, nice.
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Quoting Jeff9641:


It looks like NE to me as well. It appears to want to get under that convection pulling off the Yucatan. I am glad someone else is seeing this. Some think NE and I say no way.
NE? Sorry just not seeing that. Looks like N/NNW to me.
Member Since: September 2, 2009 Posts: 130 Comments: 21194
000
NOUS42 KNHC 271500 COR
WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
1100 AM EDT SUN 27 JUNE 2010
SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)
VALID 28/1100Z TO 29/1100Z JUNE 2010
TCPOD NUMBER.....10-027 CORRECTION

I. ATLANTIC REQUIREMENTS
1. TROPICAL STORM ALEX
FLIGHT ONE - NOAA 49
A. 29/0000Z
B. NOAA9 0601A ALEX
C. 28/1730Z..........CORRECTED
D. NA
E. NA
F. 41,000 TO 45,000 FT

FLIGHT TWO - TEAL 70
A. 29/0000, 0600Z
B. AFXXX 0701A ALEX
C. 28/2030Z
D. 21.1N 93.4W
E. 28/2300Z TO 29/0600Z
F. SFC TO 10,000 FT

FLIGHT THREE - TEAL 71
A. 29/1200, 1800Z
B. AFXXX 0801A ALEX
C. 29/0845Z
D. 21.8N 94.2W
E. 29/1100Z TO 29/1800Z
F. SFC TO 10,000 FT

2. SUCCEEDING DAY OUTLOOK: CONTINUE 6-HRLY FIXES.
POSSIBLE G-IV FLIGHT FOR 30/0000Z.

3. REMARKS: NOAA 42 WILL BE DOING RESEARCH FLIGHTS INTO
ALEX WITH TAKEOFFS EVERY 12 HRS FOR THE NEXT TWO DAYS.
(28/0800Z, 28/2000Z ETC.) OPERATING ALTITUDE 12,000 FT.



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Quoting StormW:


I don't know if the G4 has taken off yet, Levi...but I agree with you on track...I have some reservations about that ridge building...not that it won't, but my gut feeling, looking at the way the evolution of it is taking shape, could allow for a temporary move back to the NW or WNW, before another approaching trof. See what you think:



The G4 has put 5 dropsondes in so far.
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Ok, how does one post links here? I obviously failed in my attempt.
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Quoting MiamiHurricanes09:
Don't understand why.


Wunderground has it at a Cat 2 before landfall.

http://www.wunderground.com/tropical/tracking/at201001.html
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Quoting dsenecal2009:
Latest Dropsonde (3:41pm CDT)

Product: NOAA Temp Drop (Dropsonde) Message (UZNT13 KWBC)
Transmitted: 28th day of the month at 20:41Z
Aircraft: Gulfstream IV-SP (G-IV) (Reg. Num. N49RF)
Storm Number: 01
Storm Name: Alex (flight in the North Atlantic basin)
Mission Number: 6
Observation Number: 08

Part A...

Date: Near the closest hour of 20Z on the 28th day of the month
Highest Mandatory Level For Which Wind Was Reported: 200mb
Coordinates: 23.0N 87.1W
Location: 129 miles (208 km) to the N (352°) from Cancún, Quintana Roo, México.
Marsden Square: 081 (About)

Level Geo. Height Air Temp. Dew Point Wind Direction Wind Speed
1002mb (29.59 inHg) Sea Level (Surface) Pressure extrapolated between surface and 850 mb level since sonde did not reach surface.
1000mb Information Unavailable
925mb 703m (2,306 ft) 22.8°C (73.0°F) 21.9°C (71.4°F) 130° (from the SE) 38 knots (44 mph)
850mb 1,438m (4,718 ft) 19.4°C (66.9°F) 15.1°C (59.2°F) 140° (from the SE) 34 knots (39 mph)
700mb 3,090m (10,138 ft) 12.0°C (53.6°F) Approximately 6°C (43°F) 145° (from the SE) 38 knots (44 mph)
500mb 5,820m (19,094 ft) -5.1°C (22.8°F) -6.4°C (20.5°F) 155° (from the SSE) 32 knots (37 mph)
400mb 7,550m (24,770 ft) -13.9°C (7.0°F) -16.2°C (2.8°F) 200° (from the SSW) 24 knots (28 mph)
300mb 9,680m (31,759 ft) -27.9°C (-18.2°F) -28.6°C (-19.5°F) 255° (from the WSW) 10 knots (12 mph)
250mb 10,960m (35,958 ft) -37.3°C (-35.1°F) Approximately -52°C (-62°F) 275° (from the W) 20 knots (23 mph)
200mb 12,460m (40,879 ft) -49.7°C (-57.5°F) Reading usually unavailable when air temperature is below -40°C (-40°F) 305° (from the NW) 23 knots (26 mph)
150mb 14,290m (46,883 ft) Height extrapolated since sonde was released within 25mbs below this level.


And that one was north of the northeast tip of the Yucatan. Here's the flight pattern so far.

Member Since: November 24, 2005 Posts: 635 Comments: 26654

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

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