Models Develop a Disturbance Near Florida (Is invest 90L)

[jaxfladude]

I am now getting a bit worried for too much rain in too short of a period of time for some parts of Florida, if and when, this system should come to pass.....

[jinftl]

Mother Nature always balances things out....although speaking personally, i would not like to see the 16-month rainfall deficit we have here in fort lauderdale of 23.51" (for period 1/1/08 thru 5/14/09 per NWS Miami) made up for in a day or two event....have a feeling at some point this season, we will see such an event....too many areas of the state have huge deficits...too soon to say if this is a candidate....but all of a sudden, the 2009 season, in terms of analyzing models, atmospheric conditions, etc has begun!

:uarrow: I am now getting a bit worried for too much rain in too short of a period of time for some parts of Florida, if and when, this system should come to pass.....

[AdamFirst]

In case it does develop and enter the Peninsula, where would it exactly enter? Big bend area?

[HURAKAN]

[Aric Dunn]

Oh CMC! stop please!

no worries on the cmc .. SST's would not support a system that strong.. they are mid to upper 70's in the NE gulf

[gatorcane]

Aric Dunn, SSTs in most of the Gulf are above 80F and by next week will be above 80F along the Northern GOM also.

The main issue will be the dry air and shear that should keep it weak.

[Aric Dunn]

12z UKMET also turns bullish

Wow,when you see UKMET doing this,it will happen.This model is the most conservative one.



http://moe.met.fsu.edu/cgi-bin/ukmtc2.c ... =Animation

as for the UKMET
it is very conservative and deserves paying attention to ! but that run seems a little suspect on intensity and phase. it develops over SE Florida strengthens over central Florida than seems to redevelop over the cool waters of the NE gulf. I would say that the differences in model runs show us that they do not have a handle on the genesis part and if it will be a hybrid or tropical. it is clear however that a upper low will be in that area with a developing surface reflection, so i would have to lean towards a hybrid/sub-tropical system at best as of right now since the ssts are marginal at best over the NE gulf and the likelyhood of a weak upper low. The other possibility is that the low forms farther south and sits around gaining more tropical characteristics, then accelerating in some northerly component and being able to maintain some intensity. Either way it is clear something is going to develop and needs watching. Im just not going to go with any full tropical development as of yet. But depending on the strength of the upper low that develops, this upper low will help determine any possible purely tropical system, since a weaker upper low will like weaken faster opening up the tropical possibility vs. and stronger upper low keeping the system more of a sub-trop system or even more cold core. it remains to be seen what the actual development will be with all the difference in the models. the only consensus in the models is that some upper low and corresponding surface low will develop near the Southern GOM. just have to watch and wait. we will no more tomorrow when the upper low begins to take shape.

[Aric Dunn]

Aric Dunn, SSTs in most of the Gulf are above 80F and by next week will be above 80F along the Northern GOM also.

The main issue will be the dry air and shear that should keep it weak.

please check the buoy's in the area the sst maps are averages realtime is the only way to truly be sure. also the depth of the 26 c temps are very shallow within a few meters at best right now which is why any sort of storm that is purely tropical would have a hard time to strengthen...

just took another look and the highest water temp is only 78 F marginal at best for development let alone strengthening.

[gatorcane]

Aric Dunn, SSTs in most of the Gulf are above 80F and by next week will be above 80F along the Northern GOM also.

The main issue will be the dry air and shear that should keep it weak.

please check the buoy's in the area the sst maps are averages realtime is the only way to truly be sure. also the depth of the 26 c temps are very shallow within a few meters at best right now which is why any sort of storm that is purely tropical would have a hard time to strengthen...

Well if the UKMET bullish its very likely to happen -- that is a very conservative model with tropical cyclogenesis.

The sun angle is high in the sky now and the GOM is shallow, allowing it to warm rapidly. Here is Reynold's SST analysis, plenty warm enough to support a tropical system in the GOM, if other conditions were favorable for it (which should not be).

A sheared tropical storm not out of the question though.

[cycloneye]

90L by Monday?

[Aric Dunn]

Aric Dunn, SSTs in most of the Gulf are above 80F and by next week will be above 80F along the Northern GOM also.

The main issue will be the dry air and shear that should keep it weak.

please check the buoy's in the area the sst maps are averages realtime is the only way to truly be sure. also the depth of the 26 c temps are very shallow within a few meters at best right now which is why any sort of storm that is purely tropical would have a hard time to strengthen...

Well if the UKMET bullish its very likely to happen -- that is a very conservative model.

The sun angle is high in the sky now and the GOM is shallow, allowing it to warm rapidly. Here is Reynold's SST analysis, plenty warm enough to support a tropical system:

unfortunately... thermodynamic properties of saltwater would suggest only slight warming on the order of magnitude of fractions of a degree during that time frame from till development. so again with a 78 degree sst in the NE gulf not the SE or S GOM does not support a purely tropical system strengthening..

[Aric Dunn]

90L by Monday?

most likely !!

[gatorcane]

The convection is definitely increasing now and is spreading into the NW Caribbean:

[Aric Dunn]

26 degree isotherm showing minimal ssts in the NE gulf with most area at ZERO depth!

[gatorcane]

When will they start running the GFDL and HWRF -- two excellent models in my opinion?

[cycloneye]

When will they start running the GFDL and HWRF -- two excellent models in my opinion?

When 90L goes up,you will see those two.

[jinftl]

Where some of the models are suggesting the genesis of a system, there is plenty of deep, warm water....the current 26C isotherm depth...




Even a fair amount of TCHP (tropical cyclone heat potential)




If a system were to develop in the nw caribbean or off cuba/florida straits, it would be more of a question of whether it could maintain itself in the waters off the west coast of fl and the panhandle....i wouldn't expect rapid weakening with 78-80 deg water. Then again, we are probably talking more of a gusty rainmaker than a Katrina-undergoing-RI, and a wet, sloppy system could handle the water temps...marginal system (on spectrum of storms) and marginal water temps...probably would work out. Would 78 degree water support a strong eyewall for long....probably not....but a subtropical system or td/ts....i would think.

[Aric Dunn]

well here is some sst measurements for the eastern Gulf
http://www.nodc.noaa.gov/dsdt/cwtg/egof_tmap.html

[gatorcane]

I checked the SSTs in the GOM based on NOAA reports. Here is what they are:

Station 42039 - 79.5F (about 150 miles South of Pensacola)
Station 42012 - 81.5F (about 25 miles off of Mobile, Alabama)
Station 42004 - 81.7F (about 200 miles West of Naples, FL)

Generally, we are seeing 78F-81F in the GOM from north to south respectively. Are these August temperatures? No.

The minimum threshold for supporting tropical storms is 78F -- and with about 1+ week of late May sun until something even gets into the Northern GOM, I really do expect at least 1F-2F degree warming in about a week.

link:
http://www.ndbc.noaa.gov/

[jlauderdal]

you start seeing vertically stacked and surface low in the same writeup over tropical waters around hurricane season you take notice. its still May so no need to go crazy but its a very interesting setup to watch develop the next few days as there is plenty of weather coming together at once, it will be worth watching to see how it all plays out in the final solution


AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIAMI FL
215 PM EDT SAT MAY 16 2009

DISCUSSION
LOOKS LIKE THIS FORECAST PACKAGE WILL BE SOMEWHAT
STATUS QUO AT LEAST THROUGH SUNDAY AND NO DOUBT EVEN INTO MONDAY.
MODELS ARE COMING MORE IN LINE WITH MID LEVEL AND SURFACE FEATURES
DEVELOPMENT BUT STILL ARE ALL OVER THE PLACE IN TIMING AND
LOCATION ISSUES. ALL OF THE MODELS ARE DIGGING STRONG TROUGH INTO
THE SOUTHEAST STATES AND THEN CUTTING OFF A MID LEVEL LOW AT THE
BASE OF THE TROUGH EARLY NEXT WEEK. THIS WILL AID IN THE PULLING
OF DEEPER LAYER MOISTURE NORTHWARD AND BEGIN TO INCREASE CHANCES
OF RAIN AS EARLY AS SUNDAY. THE GFS, NAM AND ECMWF ALL CONTINUE
SURFACE AND MID LEVEL RIDGING TO THE NORTH OF OUR REGION WITH DEEP
SOUTHEAST FLOW. THE GFS AND NAM FORECAST SOUNDINGS SHOW PWAT
INCREASING TO ABOVE 1.5 INCHES WHILE THE ECMWF KEEPS IT UNDER BUT
OVERALL PATTERN WILL BE SIMILAR TO TODAY ALBEIT A LITTLE MORE
COVERAGE IN RAINFALL. THAT IS TO SAY, BEST CHANCES OF RAINFALL
ALONG THE EAST COAST WILL BE LATE TONIGHT/SATURDAY MORNING
SHIFTING TO THE INTERIOR AND SOUTHWEST COAST BY AFTERNOON AND
EVENING. BY MONDAY, MOISTURE WILL INCREASE EVEN FURTHER AS MID
LEVEL LOW CONTINUES TO DEEPEN INTO THE NORTHEAST GULF OF MEXICO.
HOWEVER, THIS IS ALSO WHEN THE FORECAST BEGINS TO GET A LITTLE
HAZY. THE NAM IS THE QUICKEST TO CUTTING OFF A MID LEVEL LOW BY
MONDAY AND EVEN DEVELOPS A SURFACE LOW OVER THE YUCATAN CHANNEL
LATE SUNDAY WHICH SEEMS SUSPECT AS THE MID/UPPER FEATURE IS STILL
FAR TO THE NORTH OF THAT REGION AT THAT TIME. IT THEN DEVELOPS A
FULLY DEVELOPED VERTICALLY STACKED SYSTEM ON TUESDAY OVER THE
SOUTHEAST GULF OFF THE NORTHWEST COAST OF CUBA. THE GFS SHOWS THE
LOW BEGINNING TO CUT OFF OVER THE EASTERN GULF WITH SURFACE LOW
DEVELOPING OVER THE FL STRAITS MONDAY NIGHT. ITS SYSTEM GETS FULLY
DEVELOPED BY LATE TUESDAY WITH PWAT INCREASING TO TWO PLUS INCHES
ACROSS SOUTH FLORIDA. IT THEN DRIFTS THE LOW TO THE NORTH THROUGH
THE END OF THE WEEK. THE ECMWF DOES NOT CUT OFF A LOW UNTIL LATE
TUESDAY BUT ALSO OVER THE SOUTHEAST GULF WITH A FULLY DEVELOPED
LOW NOT UNTIL AT LEAST MID WEEK AND THEN DRIFTS IT NORTH INTO NEXT
WEEKEND. HAVING SAID THIS HANDFUL, IT APPEARS WE WILL BE GETTING
SOME MUCH BENEFICIAL RAINFALL THIS NEXT WEEK BUT WHAT REMAINS TO
BE SEEN IS THE AMOUNT OF THIS RAINFALL AND THE STRENGTH OF THE
CONVECTION WHICH WILL BE DETERMINED BY POSITION OF BOTH SURFACE
AND MID LEVEL FEATURES. STAY TUNED