[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 011040
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT FRI JUN 01 2012

TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL
AMERICA...GULF OF MEXICO...CARIBBEAN SEA...NORTHERN SECTIONS
OF SOUTH AMERICA...AND 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1015 UTC.

...TROPICAL WAVES...

AN ATLANTIC OCEAN TROPICAL WAVE IS ALONG 28W S OF 15N MOVING W
NEAR 15 KT. GLOBAL MODELS ARE IN GENERAL AGREEMENT ON THE
PLACEMENT OF THIS WAVE...WITH STRONGEST SIGNAL APPEARING AT 700
HPA. NO SURFACE SIGNAL HAS BEEN EVIDENT IN RECENT SCATTEROMETER
PASSES...WHILE TPW ANIMATIONS REVEAL CYCLONIC TURNING ABOUT A
MOISTURE MAXIMUM CENTERED NEAR 05.5N28W. THE DAKAR UPPER AIR
SOUNDING SHOWED THIS WAVE PASSING THE STATION ALOFT AROUND 12Z
ON 30 MAY.  SCATTERED MODERATE ISOLATED STRONG CONVECTION IS
NOTED WITHIN 120 NM OF 06N27W...AND HAS DIMINISHED SLIGHTLY IN
THE PAST FEW HOURS. THE NEXT TROPICAL WAVE IS SUGGESTED ALONG
10W AND POISED TO EXIT W AFRICA IN THE NEXT 12-18 HRS.

A WEAKENING AND ILL DEFINED CARIBBEAN TROPICAL WAVE IS ESTIMATED
FROM W VENEZUELA ALONG 70W THROUGH EASTERN PUERTO RICO TO NEAR
22N66W. STRAIGHT LINE SELY WINDS ACROSS THIS REGION BELOW 700
HPA ARE AIDING IN MASKING THE WAVE SIGNAL AND WEAKENING THE WAVE
STRUCTURE. TPW ANIMATIONS SHOW HIGHEST MOISTURE CONTENT
ASSOCIATED WITH THE WAVE S OF 15N. 40-50 KT OF NW WIND SHEAR
ASSOCIATED WITH AN UPPER TROUGH EXTENDING INTO THE ERN CARIBBEAN
IS ALSO ACTING TO DECAPITATE ASSOCIATED CONVECTION. SAL BEHIND
THE WAVE HAS MOVED ACROSS THE LEEWARD ISLANDS AND IS NOW ACROSS
THE FAR NE CARIBBEAN...PROVIDING THE POTENTIAL FOR WIND GUSTS
25-30 KT IN SCATTERED SHOWERS AND SQUALLS WITH AND BEHIND THE
WAVE. SCATTERED SHOWERS AND A FEW TSTMS ARE SPREAD ACROSS THE SE
CARIBBEAN AND THE WINDWARD ISLANDS BUT ARE BEING DESTROYED BY
THE STRONG WIND SHEAR W OF 63W.

...THE ITCZ/THE MONSOON TROUGH...

THE MONSOON TROUGH IS ANALYZED EMERGING OFF THE COAST OF SENEGAL
NEAR 13.5N16W TO NEAR THE TROPICAL WAVE AT 07N26W. THE ITCZ AXIS
BEGINS W OF THE TROPICAL WAVE ALONG 27W NEAR 05N29W TO THE MOUTH
OF THE AMAZON ALONG THE EQUATOR NEAR 50W.  WIDELY SCATTERED
MODERATE CONVECTION IS NOTED WITHIN 210 NM S OF THE MONSOON
TROUGH BETWEEN 18W AND 23W. SCATTERED MODERATE CONVECTION IS
NOTED WITHIN 90 NM N AND 150 NM S OF ITCZ AXIS BETWEEN 32W AND
40W ASSOCIATED WITH A WEAK PERTURBATION AHEAD OF THE TROPICAL
WAVE.

...DISCUSSION...

THE GULF OF MEXICO...
PERSISTENT HIGH AMPLITUDE RIDGING ACROSS THE W CARIBBEAN N-NE TO
BEYOND 32N74W HAS MAINTAINED ELONGATED MIDDLE/UPPER TROUGHING
FROM THE N CENTRAL GULF SW THROUGH S CENTRAL GULF THE PAST FEW
DAYS. A NEGATIVE TILT MIDDLE/UPPER CYCLONE EMBEDDED WITHIN A
CENTRAL U.S. UPPER TROUGH IS SWEEPING EWD ACROSS THE N CENTRAL
GULF COAST AND HAS BEEN IGNITING VERY ACTIVE CONVECTION ALONG
AND AHEAD OF A FRONTAL BOUNDARY NOW EXTENDING FROM THE CENTRAL
LOUISIANA COAST TO THE LOWER TEXAS COAST. THE UPPER CYCLONE
CONTINUES TO MOVE SWEEP GRADUALLY E AND IS NUDGING THE LINGERING
TROUGH EWD AHEAD OF IT...AND ARE LIKELY TO MERGE ACROSS THE NE
GULF LATER TODAY. AN ELONGATED VORT CENTER HAS SLOWLY EJECTED
FROM THE BASE OF THE LINGERING TROUGH DURING THE PAST 24
HOURS...AND WAS MOVING NE ACROSS THE YUCATAN CHANNEL AND TOWARDS
EXTREME SW FLORIDA THIS MORNING. THIS FEATURE IS PROVIDING
VERTICAL LIFT ACROSS A ZONE OF ABUNDANT MOISTURE RESIDING ACROSS
THE FAR NW CARIBBEAN AND SE GULF...INDUCING SCATTERED STRONG
CONVECTION FROM LA ISLA DE JUVENTUD CUBA N AND NE ACROSS THE W
END OF CUBA...THE SE GULF AND INTO EXTREME S FLORIDA. 09Z
SURFACE PRES ANALYSIS SUGGESTS A TROUGH MAY HAVE FORMED NE TO SW
FROM OFFSHORE OF THE YUCATAN PENINSULA TO SW FLORIDA COASTAL
WATERS AND MAY ACT AS A FOCUSING MECHANISM FOR VERY HEAVY
RAINFALL THIS MORNING. WITH ABUNDANT MOISTURE AND DYNAMICS IN
PLACE TODAY...THERE IS THE POTENTIAL FOR VERY HEAVY RAINFALL
FROM THE STRAITS OF FLORIDA NE ACROSS S FLORIDA THROUGH THIS
AFTERNOON AND EVENING.

THE CARIBBEAN SEA...
A WEAKENING TROPICAL WAVE IS OVER THE E CARIBBEAN...AND
CONTINUES TO BE STRONGLY SHEARED BY UPPER TROUGH EXTENDING
INTO THE NE CARIBBEAN. SEE DISCUSSION ABOVE. A LARGE AREA OF
SCATTERED TO NUMEROUS MODERATE TO STRONG CONVECTION ACROSS
CENTRAL AMERICA FROM 10N TO 17N W OF 82W OVERNIGHT HAS
DIMINISHED AS SHORTWAVE ENERGY MENTIONED ABOVE HAS LIFTED NE
INTO THE SE GULF. AN UPPER RIDGE IS CENTERED ON AN ANTICYCLONE
NEAR 14N79W WITH SUBSIDENCE TO THE E ACROSS THE CENTRAL AND S
CENTRAL CARIBBEAN TO 65W. MODERATE TO FRESH E-SE TRADE WINDS
PREVAIL ACROSS THE CENTRAL CARIBBEAN W OF THE TROPICAL
WAVE...WITH SLY FLOW OPENING UP INTO THE GULF THROUGH THE
YUCATAN CHANNEL. SAL BEHIND THE TROPICAL WAVE HAS ENTERED THE NE
CARIBBEAN.

THE ATLANTIC OCEAN...
A MIDDLE/UPPER LEVEL CYCLONE CENTERED NEAR 28N56W IS CUT OFF
FROM THE MEAN UPPER FLOW BUT IS CURRENTLY BEING NUDGED EWD BY
UPSTREAM PROGRESSIVE SHORTWAVE ENERGY MOVING OVER THE TOP OF W
CARIB RIDGE N OF 35N. ELEVATED CONVECTION IS OCCURRING BETWEEN
50W AND 60W ASSOCIATED WITH THIS CUT OFF UPPER CYCLONE. AN
ASSOCIATED UPPER TROUGH EXTENDS SW INTO NE CARIBBEAN TO NEAR
11N63W. AN UPPER RIDGE PREVAILS SE OF TROUGH ACROSS THE TROPICAL
ATLC S OF 20N FROM W COAST OF AFRICA TO NEAR 60W. A 1022 MB
SURFACE HIGH IS CENTERED NEAR 24N48W WITH RIDGE EXTENDING E TO
32W AND W TO NEAR THE NW BAHAMAS. MODERATE TO FRESH NE
TRADEWINDS ARE FOUND S OF THIS RIDGE BETWEEN 30W AND 55W...WHERE
A VERY EXPANSIVE AREA OF SAL DOMINATES MUCH OF THE TROPICAL
ATLC...S OF 20N TO NEAR THE ITCZ...AND FROM THE TROPICAL WAVE W
TO NEAR 60W. A MID LATITUDE COLD FRONT ENTERS NE PORTIONS FROM
NEAR 31N24W TO 29N32W WITH WEAK STRATIFORM PRECIP ALONG AND TO
120 NM SE OF THIS DYING FRONT. MULTI LAYERED LOW AND MIDDLE
LEVEL CLOUDS ARE SEEN ACROSS THE SUBTROPICAL ATLC BETWEEN THE
BAHAMAS AND 50W WITH WIDELY SCATTERED PATCHES OF LIGHT TO
MODERATE CONVECTION WITH A FEW ISOLATED TSTMS OCCURRING BETWEEN
THE BAHAMAS AND 60W. AS MENTIONED IN THE GULF OF MEXICO
SECTION...STRONG AND ACTIVE CONVECTION MOVING NE ACROSS THE
STRAITS OF FLORIDA AND EXTREME S FLORIDA HAS RECENTLY BEGUN TO
EXIT THE SE FLORIDA COAST AND SPREAD NE INTO THE ADJACENT
COASTAL WATERS TO JUST N OF THE NW BAHAMAS. THIS TREND IS
EXPECTED TO CONTINUE TODAY WITH THIS CONVECTION EXPECTED TO TO
SHIFT NE AND E ACROSS THE S AND CENTRAL FLORIDA COASTAL WATERS
AND ACROSS THE N HALF OF THE BAHAMAS.

FOR ADDITIONAL INFORMATION PLEASE VISIT
HTTP://WWW.HURRICANES.GOV/MARINE

$$
STRIPLING





This weather bulletin was brought to you by:
www.nashvilleweather.net