[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 241124
TWDAT

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT SUN MAY 24 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1015 UTC.

...TROPICAL WAVES...
A TROPICAL WAVE IS ALONG 50W S OF 10N MOVING W NEAR 18 KT. THIS
WAVE IS ASSOCIATED WITH A MAXIMUM IN DEEP LAYER MOISTURE BASED
ON THE TOTAL PRECIPITABLE WATER PRODUCT FROM CIMSS. SATELLITE
IMAGERY INDICATES THAT THE WAVE IS EMBEDDED WITHIN AN INVERTED-V
CLOUD SIGNATURE...WITH CYCLONIC CIRCULATION IN THE MOTION OF THE
LOW LEVEL CLOUDS IN THE VICINITY OF THE WAVE AXIS. SCATTERED
MODERATE CONVECTION IS WITHIN 300 NM E OF THE WAVE AXIS S OF 4N.

...THE ITCZ...
THE ITCZ AXIS IS CENTERED ALONG 6N10W 4N17W 2N26W CROSSING THE
EQUATOR NEAR 33W EXTENDING JUST S OF THE EQUATOR TO THE COAST OF
NE BRAZIL NEAR 1S47W. SCATTERED MODERATE CONVECTION IS WITHIN 50
NM OF A LINE FROM 3N4W TO 1N12W. SIMILAR CONVECTION IS ALSO S OF
3N BETWEEN 35W-49W.

...DISCUSSION...

GULF OF MEXICO...
A DEEP LAYER TROUGH IS PRESENT ACROSS THE GULF WITH AN AXIS
EXTENDING FROM AN UPPER LOW OVER LOUISIANA NEAR 31N93W TO THE
ERN STRAITS OF FLORIDA NEAR 24N80W. AN ASSOCIATED 1006 MB
SURFACE LOW IS LOCATED INLAND ACROSS CENTRAL MISSISSIPPI NEAR
33N90W...WITH A SURFACE TROUGH EXTENDING FROM THE LOW ACROSS THE
EXTREME WRN FLORIDA PANHANDLE INTO THE GULF NEAR 30N87W
EXTENDING TO 24N89W. LOW LEVEL CONVERGENCE ALONG THE SURFACE
TROUGH...AS WELL AS UPPER LEVEL DIFFLUENCE NE OF THE UPPER
TROUGH AXIS...ARE SUPPORTING SCATTERED SHOWERS AND ISOLATED
TSTMS ACROSS THE NE GULF NE OF A LINE FROM WRN CUBA NEAR 23N83W
TO GULFPORT MISSISSIPPI NEAR 30N89W. UPPER DIFFLUENCE NEAR THE
BASE OF THE UPPER TROUGH IS GENERATING SCATTERED SHOWERS AND
TSTMS ACROSS THE FLORIDA STRAITS E OF 81W. AS THE SURFACE LOW
CONTINUES MOVING N-NW MAINLY LIGHT SOUTHERLY SURFACE FLOW WILL
PREVAIL ACROSS THE ENTIRE GULF THROUGH TUES AND GRADUALLY
INCREASE AS THE NEXT AREA OF LOW PRESSURE DEVELOPS ACROSS THE
SRN PLAIN STATES. ACROSS THE SW GULF...DEEP LAYER DRY AIR AND
SUBSIDENCE ASSOCIATED WITH W-NW FLOW ALOFT AND A WEAK 1014 MB
SURFACE HIGH CENTERED NEAR 24N93W IS SUPPORTING GENERALLY FAIR
WEATHER CONDITIONS.

CARIBBEAN SEA...
SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING ACROSS THE
CARIBBEAN N OF 17N E OF 80W AND THE ADJACENT COASTAL WATERS
ALONG THE SRN COAST OF CUBA. THIS ACTIVITY IS BEING SUPPORTED BY
UPPER LEVEL DIFFLUENCE IN MOIST WESTERLY FLOW ALOFT BETWEEN AN
UPPER LEVEL TROUGH EXTENDING FROM THE GULF OF MEXICO TO OVER THE
NW CARIBBEAN...AND AN UPPER LEVEL RIDGE ACROSS THE SW NORTH
ATLC. THIS SYNOPTIC PATTERN HAS PERSISTED FOR THE PAST FEW DAYS
AND IS RESULTING IN CONTINUED PRECIPITATION ACROSS CUBA...
JAMAICA...HISPANIOLA...PUERTO RICO AND THE NEARBY COASTAL WATERS
ACROSS THE NRN CARIBBEAN. THE UPPER TROUGH IS FORECAST TO DRIFT
SLOWLY EWD AND BEGIN WEAKENING BY LATE MONDAY. ADDITIONAL
SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING ACROSS
CENTRAL AMERICA AND THE SW CARIBBEAN WATERS SW OF A LINE FROM
18N88W TO 11N75W. INCLUDED IN THIS AREA IS A 1009 MB COLOMBIA
SURFACE LOW AND THE EWD EXTENSION OF THE E PACIFIC ITCZ AXIS
ACROSS PANAMA. THIS ACTIVITY IS ALSO BEING SUPPORTING BY UPPER
LEVEL DIFFLUENCE ON THE EXTENSION OF AN UPPER LEVEL RIDGE FROM
THE E PACIFIC REGION EWD TO 65W. MEANWHILE...THE SURFACE
PRESSURE GRADIENT S OF A SURFACE RIDGE OVER THE W ATLC IS
MAINTAINING ELY TRADES OF 20 TO 25 KT ACROSS PORTIONS OF THE ERN
CARIBBEAN.

ATLANTIC OCEAN...
SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING SW OF A LINE
FROM 32N81W NEAR THE SRN SOUTH CAROLINA COAST TO N OF THE
LEEWARD ISLANDS NEAR 20N61W. THIS AREA INCLUDES THE BAHAMAS...
TURKS AND CAICOS ISLANDS...GREATER ANTILLES AND ADJACENT NEARBY
COASTAL WATERS ALONG THE ERN FLORIDA PENINSULA. THIS ACTIVITY IS
BEING SUPPORTED BY UPPER LEVEL DIFFLUENCE IN MOIST SWLY FLOW
ALOFT BETWEEN AN UPPER LEVEL TROUGH OVER THE GULF OF MEXICO AND
AN UPPER LEVEL RIDGE OVER THE SW NORTH ATLC. FARTHER TO THE E...
AN UPPER LEVEL TROUGH IS PRESENT WITH AN AXIS EXTENDING FROM AN
UPPER LEVEL LOW NEAR 33N46W TO 26N55W TO 24N61W. ATMOSPHERIC
INSTABILITY NEAR THE UPPER LEVEL LOW AND TROUGH...AS WELL AS
UPPER LEVEL DIFFLUENCE IN MOIST SWLY FLOW ALOFT...ARE SUPPORTING
SCATTERED MODERATE CONVECTION N OF 28N BETWEEN 36W-47W. ALSO...A
SURFACE TROUGH EXTENDS FROM A 1018 MB SURFACE LOW NEAR 32N46W SW
ALONG 28N49W INTO A 1017 MB LOW NEAR 25N52W AND CONTINUING ALONG
23N55W TO N OF THE LEEWARD ISLANDS NEAR 19N62W. LOW LEVEL
CONVERGENCE NEAR THE SURFACE LOWS AND SURFACE TROUGH AXIS IS
SUPPORTING SCATTERED SHOWERS WITHIN 300 NM E OF THE TROUGH AXIS.
ACROSS THE E ATLC...A SURFACE RIDGE IS PRESENT WHERE MAINLY
ZONAL FLOW ALOFT IS OCCURRING AND FAIR WEATHER CONDITIONS
PERSIST. ACROSS THE TROPICAL ATLC...AN UPPER LEVEL RIDGE IS S OF
6N E OF 55W. UPPER LEVEL DIVERGENCE ASSOCIATED WITH THE UPPER
LEVEL RIDGE IS ENHANCING CONVECTION ASSOCIATED WITH THE ITCZ AND
THE TROPICAL WAVE ALONG 50W.

$$
HUFFMAN





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