[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 250005
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
805 PM EDT FRI APR 24 2015

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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2345 UTC.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 06N10W SW
TO 03N14W TO 03N18W WHERE THE INTERTROPICAL CONVERGENCE ZONE
AXIS CONTINUES TO 01S31W 02S40W TO THE NORTHERN COAST OF BRAZIL
NEAR 01S51W. SCATTERED MODERATE CONVECTION IS FROM 08S TO 01N W
OF 32W.

...DISCUSSION...

GULF OF MEXICO...

A MIDDLE TO UPPER LEVEL LOW CENTERED OVER MAINE SUPPORTS A
COMPLEX SURFACE LOW PRESSURE SYSTEM OVER THE W-NW ATLC. THE LOW
AND ASSOCIATED TROUGHING ALOFT SUPPORTS A COLD FRONT ENTERING
THE DISCUSSION AREA IN THE SW NORTH ATLC...WHICH THEN
TRANSITIONS TO A STATIONARY FRONT NEAR FORT MYERS AND CONTINUES
ACROSS THE NE GULF ALONG 26N82W TO SE LOUISIANA NEAR 29N90W.
SOUTHEASTERLY TO SOUTHERLY WIND FLOW OF 5 TO 15 KT IS BANKING
LOW LEVEL MOISTURE ALONG THE NORTHERN GULF...THUS SUPPORTING FOG
ON THE NW BASIN N OF 26N W OF 90W AND SCATTERED MODERATE
CONVECTION AND TSTMS WITHIN 200 NM E OF THE STATIONARY FRONT N
OF 29N. OVER THE SE GULF...SOUTH OF THE FRONT...A WEAK CENTER OF
HIGH PRESSURE OF 1014 MB IS LOCATED NEAR 25N83W. FAIR WEATHER IS
ACROSS THE REMAINDER GULF S OF 25N BEING SUPPORTED BY DRY AIR
SUBSIDENCE FROM ALOFT. A 1017 MB HIGH OVER SOUTH CAROLINA AND
GEORGIA COASTAL WATERS WILL DRIFT E DURING THE NEXT 24 HOURS
EXTENDING A RIDGE AXIS SW ACROSS THE GULF. LOW PRESSURE WILL
START TO BUILD OVER THE WESTERN GULF BY SUNDAY MORNING
ASSOCIATED WITH THE NEXT FRONTAL BOUNDARY FORECAST TO EMERGE OFF
THE TEXAS AND LOUISIANA COASTS EARLY MONDAY. A SECONDARY FRONT
IS FORECAST TO EMERGE OFF THE NW GULF COAST EARLY TUESDAY.

CARIBBEAN SEA...

AN UPPER LEVEL RIDGE CENTERED OVER THE NW CARIBBEAN ALONG WITH
DEEP LAYER DRY AIR ACROSS THE CENTRAL AND EASTERN BASIN SUPPORT
STABLE CONDITIONS AND FAIR WEATHER. LOW LEVEL MOISTURE
ASSOCIATED WITH THE COLD FRONT OVER THE SW N ATLC IS BEING
ADVECTED TO THE NW CARIBBEAN BY N-NE WIND FLOW...THUS ENHANCING
ISOLATED SHOWERS AND TSTMS OVER NW AND SOUTHERN CUBA AND
ADJACENT WATERS. OTHERWISE...AN OVERALL WEAK PRESSURE GRADIENT
SUPPORT TRADES OF 15 KT S OF 16N BETWEEN 61W AND 80W AND
VARIABLE LIGHTER WINDS ELSEWHERE. SIMILAR SYNOPTIC CONDITIONS
EXPECTED THROUGH TUESDAY.

...HISPANIOLA...

SHALLOW MOISTURE ASSOCIATED WITH THE COLD FRONT OVER THE SW N
ATLC IS BEING ADVECTED BY NORTHERLY FLOW ACROSS THE WESTERN
ISLAND. THIS MOISTURE IS SUPPORTING CLOUDINESS OVER HAITI AND
WESTERN DOMINICAN REPUBLIC WITH POSSIBLE ISOLATED SHOWERS. A
MIDDLE LEVEL DIFFLUENT ENVIRONMENT OVER THE ISLAND MAY CONTINUE
TO ENHANCE SHOWERS THROUGH SAT NIGHT.

ATLANTIC OCEAN...

A MIDDLE TO UPPER LEVEL LOW CENTERED OVER MAINE SUPPORTS A
COMPLEX SURFACE LOW PRESSURE SYSTEM OVER THE W-NW ATLC. THE LOW
AND ASSOCIATED TROUGHING ALOFT SUPPORTS A COLD FRONT ENTERING
THE DISCUSSION AREA FROM 30N65W SW TO 28N75W TO FORT MYERS WHERE
IT TRANSITIONS TO A STATIONARY FRONT ACROSS THE NE GULF.
SCATTERED SHOWERS AND TSTMS ARE AHEAD OF THE FRONT N OF 28N
BETWEEN 60W AND 68W. A SECOND COLD FROM EXTENDS FROM A 1010 MB
LOW NEAR 31N51W AND CONTINUES ALONG 25N59W TO 24N69W. NUMEROUS
MODERATE CONVECTION IS WITHIN 260 NM AHEAD OF THE FRONT N OF
23N. SURFACE RIDGING AND FAIR WEATHER PREVAILS ELSEWHERE.

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

$$
NR

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