GOM tropical development midweek?

[Stormcenter]

NWS N.O. thinks it's possible.

AM STILL MONITORING THE GULF OF MEXICO FOR ANY POSSIBLE TROPICAL
WAVE DEVELOPMENT FROM MIDWEEK ON INTO THE WEEKEND. RIGHT
NOW...THERE ARE LARGE DIFFERENCES IN THE MODELS FROM WEDNESDAY ON
INTO THE WEEKEND. THE GFS DEVELOPS A STRONG WAKE LOW IN THE REAR
QUADRANT OF JET STREAK OVER THE EASTERN GULF OF MEXICO LATE THIS
WEEK...AND THEN HAS THE LOW STALL OVER THE FLORIDA PANHANDLE THIS
WEEKEND. ON THE OTHER HAND...THE ECMWF AND DGEX BOTH DEVELOP A WEAK
TROPICAL WAVE IN THE CENTRAL GULF...AND STILL SWING IT WESTWARD
TOWARD TEXAS FOR THE WEEKEND. AT THIS TIME...HAVE DECIDED TO STRAY
AWAY FROM THE GFS SOLUTION AND LEAN MORE TOWARD THE WAVE TRAVELING
WEST AROUND THE BASE OF A STRONG MIDLEVEL RIDGE. AS THIS TROPICAL
WAVE PASSES SOUTH OF LOUISIANA ON THURSDAY...THE RIDGING WILL ERODE
ENOUGH TO ALLOW SOME RETURN FLOW OF MOISTURE BACK INTO THE REGION.
IN FACT...IT APPEARS THAT A WEAK INVERTED TROUGH WILL REMAIN OVER
THE AREA THROUGH SATURDAY NIGHT. WILL CONTINUE TO KEEP CHANCE POPS
IN FOR THE WEEKEND AS A RESULT. DUE TO ADDITIONAL CLOUD COVER AND
HIGHER POPS...ALONG WITH HIGHER OVER RH VALUES...WILL COOL
TEMPERATURES BACK TO MORE NORMAL LEVELS FOR THE WEEKEND.

[Swimdude]

*Chants*

Texas!
Texas!
Texas!

[wxman57]

*Chants*

Texas!
Texas!
Texas!

Forget it!
Florida!
Florida!
Florida!

Strong SW-WSW winds across the central and northern Gulf should drive any rain to Florida.

Hmm, looks like an all-Houston thread.

[Anonymous]

And Florida NWS offices say it wont happen at all....

Jax discussion....

MODELS BEGIN TO DIVERGE AFTER TONIGHT AS GFS IS PERSISTENT WRT
TO DEVELOPING LOW PRESSURE IN THE WESTERN CARRIBEAN...THEN TRACKING
THIS FEATURE NORTHEAST IN THE GULF OF MEXICO. WHILE THIS SCENARIO IS
PLAUSIBLE GIVEN TIME OF YEAR...GFS MODEL APPEARS TOO AGGRESSIVE AND
WILL CONTINUE TO RULE OUT THIS SCENARIO. THUS...WILL FOLLOW ETA/NGM
TRENDS OF COOLER AND SLIGHTLY DRIER CONDITIONS FILTERING IN AS
SURFACE HIGH PRESSURE NOSES SOUTH ALONG THE EAST COAST. THIS WILL
RESULT IN BELOW NORMAL TEMPS/POPS FOR MONDAY AND TUESDAY...WITH
CONDITIONS RETURNING TO MORE SEASONAL PATTERN BY WEDNESDAY.

.LONG TERM (THU THRU SUN)...MEDIUM RANGE MODELS CONTINUE TO DIVERGE
WITH PESKY GFS MODEL STALLING TROPICAL LOW OVER FLORIDA PANHANDLE.
WILL CONTINUE TO FOLLOW EUROPEAN MODEL WHICH BUILDS MEAN LAYER RIDGE
INTO THE SOUTHEAST UNITED STATES...RESULTING IN ABOVE NORMAL
TEMPERATURES AND MINIMAL RAIN CHANCES. WILL STILL NEED TO MONITOR FOR
ANY POTENTIAL DEVELOPMENT. &&

.MARINE...REPORTS COMING IN UPSTREAM OF SEAS RAPIDLY ON THE INCREASE
AND EXPECT NORTHEAST SURGE TO GRADUALLY MAKE ITS WAY DOWN INTO OUR
WATERS THROUGH THE EVENING HOURS. IT WILL BE A CLOSE CALL AS TO
WHETHER SCEC CONDITIONS WILL GET TO THE NORTHERN WATERS PRIOR TO
DAYBREAK. WILL MONITOR CONDITIONS AND MAKE THAT CALL JUST PRIOR TO
ISSUANCE. OTHERWISE...WILL STICK CLOSE TO THE NAM SOLUTION AND AWAY
FROM THE TROPICAL GFS SOLUTION.

Melbourne....

MON-THURS...AS HAS BEEN THE CASE OF LATE...THE 12Z GFS CONTINUES TO
SUFFER FROM CONVECTIVE FEEDBACK LEADING TO SPURIOUS LOW DEVELOPMENT.
WILL THEREFORE FOLLOW CLOSER TO THE NAM SOLUTION...AT LEAST THROUGH
THE EARLY PART OF THE WEEK. STRENGTHENING UPPER LEVEL JET WILL
ADVECT MOISTURE NORTHWARD FROM NW CARIBBEAN OVER THE NEXT COUPLE OF
DAYS. HIGHEST POPS IN EC FL WILL OCCUR OVER THE SOUTHERN SECTIONS...
ESPECIALLY ON MONDAY WITH OLD BOUNDARY INVIC AND HIGHER PWAT AIR
ADVECTING INTO REGION. LOWER POPS HEADING NORTH MON DUE TO SOME
LINGERING LOWER PWAT AIR BEHIND WEAK FRONTAL BOUNDARY...THEN AIR
MASS WILL GRADUALLY MOISTEN NORTHWARD TUESDAY. CONFIDENCE NOT TOO
HIGH HEADING OUT IN TIME...AS THE MEDIUM RANGE GUIDANCE HAS BEEN
INCONSISTENT AND 12Z NAM IS NOW INDICATING SOME LINGERING MID LEVEL
TROFFINESS INTO FRIDAY. WILL KEEP ZONES SPLIT TO INDICATE HIGHER POP
VALUES SOUTH THAN NORTH THROUGH MID WEEK...THEN CONTINUE A TREND
TOWARD CLIMO NORMS FOR LATTER PART OF THE WEEK.

Tampa....

.SHORT TERM (TONIGHT-TUE)...ONCE AGAIN...THE GFS MUST BE DISCOUNTED
DUE TO THE STRONG CYCLOGENESIS IN THE EASTERN GULF OF MEXICO. THE
NAM HAS CHANGED A BIT FROM YESTERDAY...WITH MOST OF THE TROPICAL
MOISTURE NOW CONFINED TO EXTREME SOUTH FLORIDA WHILE PERHAPS
CHARLOTTE AND LEE COUNTIES CATCH SOME OF THE NORTHERN FRINGES OF
THE RAIN. SINCE ALL THIS HAPPENS IN THE NEXT 24 TO 48 HOURS...A
QUICK LOOK AT THE WATER VAPOR LOOP HELPS TO SHED SOME LIGHT ON WHY
WE'VE SEEN THIS SOUTHWARD SHIFT. A DEEP UPPER-LEVEL TROUGH WITH A
LOW CENTER OVER GEORGIA IS CONTINUING TO DIG SOUTH INTO THE GULF
OF MEXICO AND OVER THE FLORIDA PENINSULA. THIS HAS BROUGHT VERY DRY
AIR INTO MOST OF THE STATE ABOVE 700 MB. THE GFS APPEARS TO WEAKEN
THIS LOW TOO QUICKLY...WHICH IS WHY IT HAS SO MUCH MOISTURE WORKING
ITS WAY BACK NORTHWARD WITH DEVELOPING LOW PRESSURE IN THE GULF.
THE NAM LOOKS MUCH MORE REASONABLE IN KEEPING A DEEP BROAD TROUGH
OVER THE EASTERN U.S. AND GULF OF MEXICO...THUS BLOCKING THE
NORTHWARD MOTION OF THE DEEPER MOISTURE.

BEST RAIN CHANCES WILL BE OUR SOUTHERN COUNTIES...ESPECIALLY LEE
AND CHARLOTTE COUNTIES WHERE SIGNIFICANT RAINFALL COULD OCCUR IF THE
DEEPER MOISTURE MAKES IT FAR ENOUGH NORTH. FOR NOW...WILL CAP POPS
AT 40 PERCENT BASED ON WATER VAPOR IMAGERY MAKING IT HARD FOR ME TO
BELIEVE THE MOISTURE WILL GET VERY FAR NORTH.

OTHERWISE...STANDARD AFTERNOON AND EVENING SUMMER-TIME CONVECTION...
ALTHOUGH COVERAGE SHOULD BE A BIT BELOW NORMAL DUE TO THE DRIER AIR
ALOFT.

&&

.LONG TERM (TUE NIGHT-SUN)...LATEST GFS STILL LOOKS OVER DONE WITH
SURFACE LOW MOVING NORTHEAST ACROSS NORTH FLORIDA WEDNESDAY AND HAVE
TENDED TO GO WITH THE DGEX SOLUTION OF SOME UPPER LEVEL TROUGHING
LINGERING OVER THE SOUTHEASTERN U.S. LEADING TO ISOLATED TO SCATTERED
SHOWERS AND THUNDERSTORMS AT ALMOST ANYTIME. BY LATE IN THE WEEK
INTO NEXT WEEKEND ALL MODELS ARE INDICATING THAT AN UPPER LEVEL RIDGE
WILL DEVELOP OVER THE SOUTHEAST U.S. WITH THE BERMUDA HIGH BECOMING
ESTABLISHED. THIS WILL SETUP A MORE TYPICAL EAST TO SOUTHEAST FLOW
ACROSS THE FORECAST AREA WHICH WILL FAVOR SCATTERED MAINLY AFTERNOON
AND EVENING CONVECTION EACH DAY. TEMPERATURES WILL BE NEAR TO
SLIGHTLY ABOVE NORMAL THROUGH THE PERIOD.

Tallahassee...

.SHORT TERM...TONIGHT THROUGH TUESDAY.
SURFACE RIDGE BUILDS IN ON MONDAY...AS THE UPPER TROUGH SETTLES OVER
THE SE U.S. MAIN LIFT & ENERGY WILL BE JUST EAST OF THE CWA...WILL
NE SURFACE FLOW WILL KEEP PRECIP WATER VALUES & INSTABILITY REMAIN
BELOW NORMAL. EXPECTING SOME SEA BREEZE FORMATION OVER N FL...BUT
CONVECTION WILL BE LIMITED WITH PREVIOUSLY MENTIONED FACTORS.
OF COURSE SOME UNCERTAINTY IN THE MODELS...ESPECIALLY THE GFS INTO
EARLY THIS WEEK WITH A POSSIBLE LOW OR TROPICAL LOW. TEMPS WILL BE
AROUND NORMAL.

&&

.LONG TERM...WEDNESDAY THROUGH SATURDAY.
QUITE A BIT OF UNCERTAINTY IN THE MODELS. WILL TAKE CONSERVATIVE
APPROACH WITH THE UPPER TROUGH HOLDING OVER THE SE U.S. NE FLOW OVER
THE CWA WILL KEEP SEA BREEZE ACTIVITY MAINLY OVER N FL. GFS BRINGS
TROPICAL LOW RIGHT OVER THE CWA WEDNESDAY TO THURSDAY...BUT WILL
HOLD OFF FROM BRING THIS SYSTEM INTO THE CWA. UPPER TROUGH EXPECTED
TO GRADUALLY LIFT NE...ALLOWING WARM-UP OVER THE SE U.S. WITH MAINLY
SEA BREEZE CONVECTION OVER THE CWA.

[clfenwi]

The feature that forms the basis for what was in the 06Z DGEX run was handled completely differently by the 12Z NAM run... not sure why the forecaster bothered mentioning the DGEX when the later NAM had already said 'oh never mind that silliness I was spouting earlier...'

The 18Z NAM run doesn't reintroduce it. The 18Z GFS, however, persists in bringing a system into the panhandle (and is probably as bogus as previous runs)...

[dhweather]

The 18Z GFS is wacko with this thing - it develops a low that comes in
east of Apalachacola, moves inland over Georgia, then Southwest
over Pensacola.

http://www.nco.ncep.noaa.gov/pmb/nwprod ... loop.shtml

[Brett Adair]

Looking at latest satellite photos from the Western Caribbean it seems that we could have something developing currently. Interesting features with some small circulation areas along the convergence zone SW of Cuba.

[Matt-hurricanewatcher]

Brett Ardair I would not be surprized if something tryed to develop even so the shear is very high. A cyclone can still develop when the shear is high but is just unoreganized/Undefined. Or a onesided. It has to do if the energy/laten heat builds with an a area to form a cyclone.

Cyclones have develops an a area of shear. But shear slows development or even stops it.

[Steve]

Nothing's going to happen anyway until the trof is done splitting. Forget the models until it changes the wind flow and let's see what happens then. Anything popping would be a pattern storm and homegrown development (maybe with a side of easterly wave).

http://weather.msfc.nasa.gov/GOES/goeseasthurrwv.html

[Swimdude]

The 18Z GFS is wacko with this thing - it develops a low that comes in
east of Apalachacola, moves inland over Georgia, then Southwest
over Pensacola.

http://www.nco.ncep.noaa.gov/pmb/nwprod ... loop.shtml

Maybe it pulls another IVAN??

I love how everyone here acts the same way... "A storm that doesn't exist yet? AHHHH CAT. FIVE!!!!!"

Ya'll are awesome.

[dhweather]

But nobody has said CAROLINAS yet.

[tailgater]

As to the original post yes I think there will be some sort of development in the gulf or nearby waters. The upper trough split or lifting out idea Steve spoke of will likely promote something to get going in area near the Yucatan, there's a weakness in place. Shear and dry air is likely to abate some. IMO

[Cookiely]

"GFS DISCONTINUED FOR THE CURRENT FORECAST"
000
FXUS62 KTBW 200626
AFDTBW

WEST CENTRAL AND SOUTHWEST FLORIDA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAMPA BAY AREA - RUSKIN FL
230 AM EDT MON JUN 20 2005

.SHORT TERM (TODAY-WED)...NO CHANGES ON GFS TENDENCY FOR STRONG
SURFACE CYCLONE OVER THE GULF BY TUESDAY. SINCE THIS SOLUTION IS
STRONGLY AFFECTING ALL OTHER FIELDS...ESPECIALLY MOISTURE AT
ALL ATMOSPHERIC LEVELS...ETA/NGM AND DGEX WILL CARRY THE WEIGHT FOR
THE FORECAST. A SPINNING MID LEVEL LOW OVER THE ATLANTIC US COAST
WILL CONTINUE TO BRING NORTHWESTERLY FLOW OVER THE AREA DURING
THE NEXT TWO DAYS ALONG WITH SOME DIRER AIR AT THE MIDDLE LEVELS. 00Z
SOUNDING SHOWING A SLOW BUT REAL TREND TO COOLING IN THE MID LEVELS
UNDER STEADY WESTERLY TO NORTHWESTERLY FLOW. ON THE OTHER HAND MODEL
DATA SHOWS A DRYING TREND AT MID LEVELS KEEPING MOST MOISTURE
CONFINED AT THE LOWER LEVELS. THEREFORE...POTENTIAL FOR SEVERE
WEATHER IS NOT A CONCERN AT THIS MOMENT.

A STEADY JET CURRENT IS BRINGING A STREAM OF MID AND HIGH LEVEL
CLOUD DECKS FROM THE TROPICS INTO THE SOUTHERN HALF OF FLORIDA. A
SURFACE BOUNDARY IS WELL ESTABLISHED RIGHT AT THE EDGE OF THE
MOISTURE FIELD WHICH WILL KEEP THE NORTHERN HALF OF THE CWA DRIER...
WITH INCREASING RAINSHOWERS OVER LEE AND CHARLOTTE COUNTIES TODAY.
PREVIOUS SHIFT INCREASED POPS TO 40 FOR THESE COUNTIES DURING THE
AFTERNOON PERIOD WHICH SEEMS REASONABLE AT THIS TIME.

WEATHER CONCERNS FOR TODAY WILL BE AGAIN SEA BREEZE CONVERGENCE IN
THE AFTERNOON BRINGING SOME SCATTERED SHOWERS AND THUNDERSTORMS NEAR
COASTAL LOCATIONS...AND MOVING INLAND IN THE EARLY EVENING.

&&

.LONG TERM (WED NIGHT-SUN)...DESPITE MODEL DIFFERENCES EARLY ON IN
THE FORECAST...THERE IS BETTER AGREEMENT IN THE LATER PERIODS. SFC
HIGH PRES WITH GENERALLY EASTERLY FLOW AND RIDGING ALOFT WILL BECOME
ESTABLISHED OVER THE AREA THRU THE LONG TERM PERIOD. THIS PATTERN
WILL RESULT IN WX THAT IS FAIRLY TYPICAL FOR THIS TIME OF YEAR...
NAMELY SCATTERED SHOWERS/TSTMS DURING THE AFTERNOON AND EARLY
EVENING ASSOCIATED WITH SEA BREEZE AND CONVERGENCE ACTIVITY...AND
ISOLATED ACTIVITY OVER THE WATER AT NIGHT. TEMPS NEAR NORMAL THRU
THE LONG TERM...GENERALLY HIGHS IN THE LOW 90S AND LOWS IN THE
LOW-MID 70S.


&&

.MARINE...WITH GFS DISCONTINUED FOR THE CURRENT FORECAST...GENERALLY
LIGHT WINDS AND SEAS ARE EXPECTED ACROSS THE WESTERN FLORIDA WATERS
WITH WINDS AROUND 5 TO 10 KNOTS AND SEAS 2 FEET.

&&

.FIRE WEATHER...NO CONCERNS.

&&

.PRELIMINARY POINT TEMPS/POPS...
TPA 90 73 89 76 / 20 20 40 20
FMY 91 73 89 75 / 40 40 40 20
GIF 90 72 91 74 / 30 30 40 20
SRQ 89 72 89 75 / 20 20 40 20
BKV 91 67 89 70 / 20 20 40 20

&&

.TBW WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...AR
LONG TERM....NP

[Wpwxguy]

Check out N.O. discussion......... Talk about uncertainty......And its been this way for days now.

000
FXUS64 KLIX 200726
AFDLIX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS LA
300 AM CDT MON JUN 20 2005

.DISCUSSION...
WOW...WHAT A DIVERGENT SOLUTION IN THE MAJOR MODEL SUITES.
BEGINNING AT 48 HOURS THE GFS AND ETA DIVERGE STRONGLY UNTIL THEY
ARE 180 DEGEES OUT OF PHASE. BY 78 HRS THE ETA HAS A SFC HIGH IN
THE SAME LOCATION THAT THE GFS HAS A TROPICAL SFC LOW...HMMMMMM.
WILL START BY GIVING A SPILL ON VERIFICATION. THE ETA IS SHOWING
SOME MUCH STRONGER WINDS AT JET LEVEL OVER S FLA AT THE 00Z
INJEST. FOCUSING ON THE MIA SOUNDING...ACTUAL WIND SPEEDS ARE
AROUND 25KTS WHILE THE ETA INITIALIZES THESE SAME WINDS AT
45KTS...QUITE A DIFFERENCE. THE GFS IS SHOWING A MUCH MORE
REALISTIC WIND REGIME WITH 30KTS. SINCE THIS IS WHERE THE GFS IS
ADVERTISING OUR WEATHER TO ORIGINATE OVER THE NEXT SEVERAL
DAYS...IT WOULD BE A STRONGER SOLUTION. BOTH MODELS ARE HAVING
TROUBLE RESOLVING TEMPS AT JET LEVEL AS BOTH ARE SHOWING -32 OVER
THE SAME MIA LOCATION THAT IS ACTUALLY -30. THE WARMER TEMP IS
DUE TO THE UPPER HIGH RIDGING NORTHWARD. BOTH MODELS ARE SHOWING
THE RIDGE FARTHER EAST THAN WHERE IT ACTUALLY IS.

LONG STORY SHORT...THE UPPER TROUGH IS INITIALIZING MUCH STRONGER
IN THE ETA WHICH WOULD SUPPORT THE STRONGER SHORT WAVE RIDING THE
BACK SIDE OF THE TROUGH WED AND THU. THE GFS IS INITIALIZED MUCH
MORE WITH REALITY SHOWING A WEAKER SOLUTION COMPARED TO THE ETA
SUPPORTING A WEAKER SHORT WAVE EVENTUALLY PHASING WITH THE LONG
WAVE TROUGH OVER THE EASTERN CONUS AS IT OPENS UP TO THE MAIN
FLOW. THIS SHORT WAVE ALONG WITH THE ROSBY WAVE WOULD TEND TO DRAW
ANY TROPICAL PLUME/SYSTEM TOWARD IT BUT ANOTHER PROBLEM THEN COMES
UP. THE SHORT WAVE MOVES OUT AND SFC TO MID LEVEL RIDGING BEGINS
BEFORE THE SFC LOW CAN BE PICKED UP BLOCKING ITS PATH NORTHWARD
LEAVING IT TO MEANDER IN THE NORTHERN GULF...SO THE GFS CLAIMS.
WILL SIMPLY NOT TOUCH ANY OF THE EXTENDED FORECAST ATTM SINCE
SOLUTIONS FROM ALL MODELS HAVE BEEN SHAKY AT BEST THE LAST 3 DAYS.
AS CONFIDENCE INCREASES...WE WILL BEGIN TO PLACE A SFC LOW WHERE
IT NEEDS TO BE IN THE MID TO EXTENDED PORTION OF THE FORECAST.

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB 90 67 91 69 / 0 0 10 0
BTR 92 68 92 72 / 0 0 10 0
MSY 90 75 91 75 / 0 0 10 0
GPT 88 68 90 70 / 0 0 10 0

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
MS...NONE.
SE LA AND MS COASTAL WATERS...NONE.

&&

$$

17




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