[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 301714
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
205 PM EDT TUE MAY 29 2006

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHEASTERN
SECTIONS OF SOUTH AMERICA...AND THE ATLANTIC OCEAN TO THE
AFRICAN COAST FROM THE EQUATOR TO 32N. THE FOLLOWING INFORMATION
IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...
AND METEOROLOGICAL ANALYSIS.

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1700 UTC.

...TROPICAL WAVES...

A TROPICAL WAVE IS ADDED TO THE SFC ANALYSIS ALONG 39W/40W S OF
14N MOVING W ABOUT 15 KT. THIS WAVE HAS WELL-DEFINED CYCLONIC
TURNING ON VISIBLE SATELLITE IMAGERY. IN ADDITION...A WIND SHIFT
AND LOW-MID LEVEL VORTICITY STRUCTURE IS EVIDENT IN THE VIS
DERIVED WINDS.  THIS WAVE IS ASSISTING IN TRIGGERING NUMEROUS
SHOWERS AND TSTMS WITHIN SEVERAL HUNDRED MILES OF THE WAVE AXIS
WITHIN THE ITCZ.

TROPICAL WAVE IS INLAND OVER SOUTH AMERICA ALONG 73W S OF 12N
MOVING W NEAR 10 KT. WAVE PLACEMENT IS BASED UPON CONTINUITY OF
THE MOVEMENT OVER THE PAST 24-48 HOURS AS LITTLE WAVE SIGNATURE
IS EVIDENT. THE WAVE WILL LIKELY MOVE INTO THE EPAC TOMORROW
AFTERNOON/NIGHT AND A FEW MODELS INDICATE THAT THE WAVE MAY
BECOME SLIGHTLY BETTER DEFINED BY THEN.

...ITCZ...
ITCZ AXIS IS CENTERED ALONG 9N13W 5N21W 4N33W 3N45W 2N51W. THE
ITCZ IS VERY ACTIVE TODAY WITH NUMEROUS SHOWERS AND TSTMS
WITHIN 240 NM EITHER SIDE OF THE AXIS W OF 18W. SOME OF THE
STRONGEST ACTIVITY IS ENHANCED BY THE TROPICAL WAVE BETWEEN
36W-45W. SCATTERED SHOWERS/ISOLATED TSTMS ARE OFF THE COAST OF
AFRICA E OF 10W FROM 2N-5N.

...DISCUSSION...
GULF OF MEXICO...
A DEEP LAYERED TROUGH EXTENDS FROM AN UPPER LOW N OF THE E
BAHAMAS INTO THE E GULF AND THE CARIBBEAN. A NARROW AMPLIFIED
UPPER RIDGE COVERS THE N CENTRAL GULF WITH THE AXIS EXTENDING
FROM 27N91W TO INLAND OVER MISSISSIPPI. UPPER LEVEL CONFLUENCE
IS PRODUCING AN AREA OF STRONG SUBSIDENCE IN THE E GULF AND OVER
FLORIDA. UPPER LEVEL DIFFLUENCE CONTINUES TO GENERATE
CONSIDERABLE CLOUDINESS AND CLUSTERS OF SCATTERED MODERATE
CONVECTION W OF 93W. AT THE SFC...A 1022 MB HIGH IS LOCATED OVER
THE APPALACHIANS. E/ENE FLOW FROM 10-15 KT IS COMMON ACROSS THE
REGION...EXCEPT FOR SE WINDS FROM 15-20 KT IN THE SW GULF.
SCATTERED SHOWERS AND TSTMS WILL LIKELY CONTINUE IN THE W GULF
FOR THE NEXT COUPLE OF DAYS. ELSEWHERE...FAIR WEATHER WILL
CONTINUE UNDER WEAK SFC RIDGING. A COLD FRONT WILL APPROACH THE
NE GULF ON FRIDAY INCREASING THE CHANCE OF RAIN OVER THE NE
SECTOR OF THE REGION.

CARIBBEAN SEA...
A UPPER RIDGE/TROUGH/RIDGE PATTERN IS ESTABLISHED OVER THE
CARIBBEAN SEA. A BROAD UPPER RIDGE IN THE EPAC EXTENDS ACROSS
MEXICO TO OVER THE YUCATAN PENINSULA W OF 85W. A DEEP LAYERED
TROUGH EXTENDS FROM AN UPPER LOW N OF THE BAHAMAS
INTO THE NW CARIBBEAN N OF 16N FROM 70W-83W. A BROAD UPPER HIGH
IN THE TROPICAL ATLC STRETCHES WWARD INTO THE CARIBBEAN E OF 70W.
MODERATELY DRY/STABLE AIR COVER MUCH OF THE CARIBBEAN. VERY DRY
AIR ALOFT IS EVIDENT OVER THE LESSER ANTILLES AND FURTHER EAST.
A CLUSTER OF MODERATE TO STRONG CONVECTION HAS DEVELOPED N OF
PANAMA FROM 9N-12N BETWEEN 77W-81W. SCATTERED SHOWERS AND
ISOLATED TSTMS MAY BE OCCURRING OVER THE NW COAST OF HAITI AND
OVER THE BAHAMAS ASSOCIATED WITH A W ATLC TROUGH. MORE DETAILS
ON THIS FEATURE WILL BE DISCUSSED IN THE ATLANTIC SECTION. TRADE
WINDS ARE MOSTLY IN THE 10-15 KT RANGE. THESE WINDS MAY PICK UP
SLIGHTLY OVER THE NEXT FEW DAYS BUT WILL REMAIN LIGHT TO
MODERATE. NO BIG CHANGES ARE IN STORE FOR THE AREA TOMORROW. GFS
SUGGEST THAT A SWATH OF TROPICAL MOISTURE MAY BECOME WIDESPREAD
IN THE CENTRAL/WEST CARIBBEAN LATE THIS WEEK.

ATLANTIC OCEAN...
A SHARP DEEP LAYERED TROUGH IS WELL ESTABLISHED IN THE W ATLC
AND NW CARIBBEAN COVERING THE AREA W OF 65W TO OVER FLORIDA.
THIS TROUGH IS SUPPORTING A FEW SFC FEATURES. A SFC TROUGH
MARKED BY A LINE OF LOW-MID CLOUDS AND EMBEDDED SCATTERED
SHOWERS RUNS FROM 31N75W TO 24N80W. A MORE IMPRESSIVE SFC TROUGH
IS ON THE FAVORABLE SE SIDE OF THE UPPER AXIS ALONG 21N74W
25N66W 30N58W. TWO WEAK LOWS ARE SITTING ON THIS TROUGH. ONE
1014 MB LOW IS LOCATED NEAR 24N67W AND THE OTHER 300 NM TO THE
NE NEAR 28N62W. AN AREA OF SCATTERED SHOWERS AND TSTMS ARE FROM
20N-25N BETWEEN 67W-71W AND FROM 28N-32N BETWEEN 58W-61W. GLOBAL
MODELS ANTICIPATE THE SOUTHERN-MOST LOW TO STRENGTHEN SLIGHTLY
AS IT PULLS NEWARD. THEY DO NOT INITIALIZE THE NORTHERN-MOST LOW
WELL. FARTHER EAST...A 1026 MB HIGH PRESSURE SYSTEM DOMINATES
MUCH OF THE CENTRAL AND E ATLC. A WEAK SFC TROUGH ALONG 45W FROM
24N-29N IS CONTAMINATING THE SFC RIDGE WITH AN AREA OF CLOUDS
AND POSSIBLY A FEW SHOWERS. HOWEVER...THIS WEAK FEATURES SEEMS
TO BE FALLING APART. IN THE UPPER LEVELS OVER THE CENTRAL AND
EASTERN ATLC...A DEEP LAYERED TROUGH IS N OF 26N FROM 24W-40W
WITH THE ASSOCIATED COLD FRONT N OF THE DISCUSSION AREA. THIS IS
SUPPLYING THE REMAINDER OF THE E ATLC WITH UPPER LEVEL ZONAL
FLOW. AN UPPER HIGH IS LOCATED IN THE TROPICAL ATLC OFF THE
COAST OF SOUTH AMERICA NEAR 5N51W WITH A RIDGE AXIS EXTENDING
ACROSS THE S CARIBBEAN. ANOTHER UPPER RIDGE EXTENDS E/W FROM OFF
AFRICA ALONG 10N TO NEAR 10N30W. UPPER LEVEL DIFFLUENCE ON THE S
SIDE OF THE RIDGE IS PROVIDING A FAVORABLE ENVIRONMENT FOR
CONVECTION ALONG THE ITCZ.

$$
CANGIALOSI






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