[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 072346
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT THU MAY 07 2009

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...METEOROLOGICAL ANALYSIS...WEATHER
OBSERVATIONS...AND RADAR.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2315 UTC.

...THE ITCZ...

THE ITCZ AXIS IS CENTERED ALONG 6N10W 2N20W CROSSING THE EQUATOR
NEAR 25W TO NE BRAZIL NEAR 3S42W. SCATTERED MODERATE ISOLATED
STRONG CONVECTION IS FROM 2N-6N E OF 19W.

...DISCUSSION...

GULF OF MEXICO...
THE GULF IS DOMINATED BY FAIR WEATHER SUPPORTED BY NWLY FLOW
ALOFT AND DRY STABLE AIR ON THE E PERIPHERY OF AN UPPER RIDGE
CENTERED OVER NW MEXICO. AT THE SFC...S TO SE WINDS ARE FAIRLY
UNIFORM ACROSS THE REGION DUE TO A QUASI-STATIONARY RIDGE AXIS
EXTENDING FROM THE W ATLC TO THE N GULF COAST. WINDS ARE
STRONGEST...15-20 KT...OVER THE W WATERS IN RESPONSE TO LOW PRES
OVER THE SRN PLAINS. LITTLE SIGNIFICANT CHANGE IN THE PATTERN IS
EXPECTED OVER THE NEXT DAY OR TWO. VISIBILITIES OF 5-7 SM ARE
BEING REPORTED BY OBSERVATION SITES IN S MEXICO WITH A SMOKE
PLUME EXTENDING N INTO THE BAY OF CAMPECHE...LIKELY REDUCING
VISIBILITIES OVER MARINE AREAS AS WELL.

CARIBBEAN SEA...
SCATTERED TO NUMEROUS SHOWERS AND TSTMS CONTINUE ACROSS THE
VIRGIN ISLANDS...PUERTO RICO...HISPANIOLA AND NEARBY WATERS N OF
16N BETWEEN 63W-71W. THIS UNSETTLED WEATHER IS BEING FUELED BY
STRONG SW FLOW ALOFT AND AN OVERALL DIFFLUENT PATTERN TO THE E
OF A SHORTWAVE TROUGH. STRONG ELY TRADES AND ASSOCIATED
LOW-LEVEL WIND SPEED CONVERGENCE IN THIS AREA ARE PROVIDING
ENHANCED LIFT. LOCALLY HEAVY RAINS ARE POSSIBLE OVER THE
AFOREMENTIONED ISLANDS. THIS UNSETTLED WEATHER IS EXPECTED TO
PERSIST FOR AT LEAST THE NEXT 24 HOURS AS THE WX PATTERN HOLDS.
ELSEWHERE...CONDITIONS ARE GENERALLY QUITE THOUGH ISOLATED
SHOWERS ARE POSSIBLE JUST ABOUT ANYWHERE...ESPECIALLY OVER THE
LESSER ANTILLES WHERE THERE IS SHALLOW MOISTURE FETCH STREAMING
IN FROM THE ATLC.

ATLANTIC OCEAN...
THERE ARE ONLY A COUPLE OF AREAS OF ACTIVE WEATHER ACROSS THE
ATLC DISCUSSION AREA THIS EVENING. ONE OF THESE IS OVER AND TO
THE N OF THE CENTRAL BAHAMAS. SCATTERED SHOWERS AND TSTMS ARE
FROM 24N-31N BETWEEN 72W-75W. THIS ACTIVITY IS BEING ENHANCED BY
A SFC TROUGH ALONG 74W AND UPPER DIFFLUENCE E OF A SHORTWAVE
TROUGH OFF THE GA/FL COAST. THE LOW-LEVEL BOUNDARY WILL LIKELY
SPLIT AND BECOME DIFFUSE OVER THE NEXT 24 HOURS WHICH SHOULD
ALLOW MUCH OF THE TSTM ACTIVITY TO DIMINISH. THE OTHER AREA OF
INTEREST IS S OF 20N BETWEEN 63W-70W...NEAR THE GREATER
ANTILLES. INSTABILITY AND DIFFLUENCE ALONG AND TO THE E OF
ANOTHER SHORTWAVE TROUGH IS ENHANCING THIS WEATHER. REFER TO THE
CARIBBEAN SECTION FOR MORE DETAILS. THE REMAINDER OF THE ATLC IS
DEVOID OF ORGANIZED DEEP CLOUDINESS SUPPRESSED BY A STABLE
ATMOSPHERE...ESPECIALLY OVER THE SUBTROPICAL E ATLC WHERE THE
FLOW IS HIGHLY CONFLUENT. OVER THE TROPICAL E ATLC...A FAIR
AMOUNT OF CONVECTION IS LOCATED WITHIN THE ITCZ E OF 15W AND
OVER AFRICA ENHANCED BY BROAD SFC LOW PRES AND AN UPPER RIDGE
CENTERED NEAR 15N5W. A CONSIDERABLE AMOUNT OF SAHARAN DUST HAS
SPREAD TO ABOUT 50W...ACCORDING TO THE CIMSS SAL PRODUCT AND THE
HAZY APPEARANCE ON EARLIER VISIBLE IMAGES.

$$
CANGIALOSI








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