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000
AXNT20 KNHC 040005
TWDAT

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
705 PM EST TUE DEC 03 2013

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
2315 UTC.

...ITCZ/MONSOON TROUGH...
THE MONSOON TROUGH AXIS EXTENDS FROM THE WEST AFRICAN COAST NEAR
10N14W TO 08N17W. THE INTERTROPICAL CONVERGENCE ZONE AXIS
EXTENDS FROM 08N17W TO 05N26W 05N36W TO 02N43W. SCATTERED
MODERATE CONVECTION IS FROM 04N-07N E OF 13W AND FROM 03N-08N
BETWEEN 17W-43W. ISOLATED SHOWERS ARE FROM 03N-06N BETWEEN 44W-
49W.

...DISCUSSION...

GULF OF MEXICO...
SOUTHERLY WIND FLOW OF 15 KT DOMINATE THE WESTERN GULF
ASSOCIATED WITH AN AREA OF LOW PRESSURE THAT EXTENDS FROM SE
COLORADO TO THIS REGION OF THE GULF. A 1015 MB HIGH OVER THE
NORTHERN BAHAMAS PROVIDES SOUTHERLY WIND FLOW IN THE RANGE OF 5-
10 KT TO THE EASTERN GULF. ALOFT...A MIDDLE TO UPPER LEVEL
ANTICYCLONE CENTERED OVER SW MEXICO NEAR 17N99W PROVIDES
NORTHWESTERLY FLOW. WATER VAPOR AND SSMI TPW IMAGERY SHOW A VERY
DRY ENVIRONMENT ACROSS THE REGION WHICH ALONG WITH STRONG WIND
SHEAR ASSOCIATED WITH THE SUBTROPICAL JET SUPPORT FAIR WEATHER.
SOUTHERLY FLOW OF 10-15 KT IS FORECAST TO PERSIST THROUGH
THURSDAY EVENING. A COLD FRONT ASSOCIATED WITH THE AREA OF LOW
PRESSURE CURRENTLY OVER COLORADO IS EXPECTED TO EMERGE OFF THE
TEXAS AND LOUISIANA COASTS BY EARLY FRIDAY INTO SATURDAY.

CARIBBEAN SEA...
N-NW DRY AND STABLE FLOW IN THE MIDDLE LEVELS IS NOTED W OF 70W
ON WATER VAPOR IMAGERY WHICH CONTINUE TO SUPPORT CLEAR SKIES AND
FAIR WEATHER ACROSS THIS REGION OF THE BASIN. OVER THE SW BASIN
S OF 10N...ISOLATED SHOWERS ARE BEING ENHANCED BY THE MONSOON
TROUGH AXIS WHICH IS ANALYZED ACROSS PANAMA TO NORTHERN COLOMBIA
NEAR 07N75W. OVER THE EASTERN CARIBBEAN...A MIDDLE-LEVEL
ANTICYCLONIC CIRCULATION CENTERED OVER THE NORTHERN LEEWARD
ISLANDS IS ADVECTING MOISTURE FROM THE ITCZ TO THE REGION E OF
70W WHICH IS SUPPORTING RAINSHOWERS ACROSS THE LESSER ANTILLES
WHILE DIVERGENCE IN THE NE CARIBBEAN SUPPORTS SHOWERS ON THE
VIRGIN ISLANDS AND VIEQUES PUERTO RICO. OTHERWISE...A SURFACE
PRE-FRONTAL TROUGH IS BEING ANALYZED FROM 25N62W IN THE ATLC SW
TO NE HISPANIOLA NEAR 19N69W TO NORTHERN JAMAICA NEAR 18N77W.
LOW-LEVEL MOISTURE CONVERGENCE ALONG THE TROUGH AXIS ALONG WITH
UPPER-LEVEL DIVERGENCE SUPPORT SCATTERED SHOWERS AND ISOLATED
TSTMS OVER ADJACENT WATERS OF NE DOMINICAN REPUBLIC AS WELL AS
EASTERN HISPANIOLA. A WEAK PRESSURE GRADIENT ACROSS THE BASIN IS
FORECAST TO PROVIDE WITH TRADEWINDS IN THE RANGE OF 10-15 KT
THROUGHOUT WED AFTERNOON. AFTERWARDS...A TIGHTER PRESSURE
GRADIENT IS EXPECTED TO DEVELOP SUPPORTING EASTERLY WINDS UP TO
20 KT ACROSS THE CENTRAL BASIN THROUGHOUT THU NIGHT.

...HISPANIOLA...
CURRENTLY A SURFACE TROUGH AXIS EXTENDS FROM 25N62W IN THE ATLC
SW TO NE HISPANIOLA NEAR 19N69W TO NORTHERN JAMAICA NEAR 18N77W.
LOW-LEVEL MOISTURE CONVERGENCE ALONG THE TROUGH AXIS ALONG WITH
UPPER-LEVEL DIVERGENCE SUPPORT SCATTERED SHOWERS AND ISOLATED
TSTMS OVER ADJACENT WATERS OF NE DOMINICAN REPUBLIC AS WELL AS
EASTERN HISPANIOLA. THE TROUGH IS EXPECTED TO MOVE NW TONIGHT
AND THEN NE ON WED MORNING. HOWEVER...A MOIST AIRMASS IS
EXPECTED TO MOVE ACROSS THE ISLAND FROM WED MORNING TO THU NIGHT
WHICH IS FORECAST TO SUPPORT RAINSHOWERS ACROSS THE
ISLAND...ESPECIALLY THE DOMINICAN REPUBLIC.

ATLANTIC OCEAN...
A MIDDLE TO UPPER LEVEL TROUGH EXTENDS FROM NEW ENGLAND TO N OF
THE GREATER ANTILLES TO SUPPORT A COLD FRONT BEING ANALYZED FROM
30N60W TO 24N69W TO 22N76W. A SURFACE PRE-FRONTAL TROUGH IS
BEING ANALYZED FROM 25N62W IN THE ATLC SW TO NE HISPANIOLA NEAR
19N69W TO NORTHERN JAMAICA NEAR 18N77W. SCATTERED MODERATE
CONVECTION IS OCCURRING N OF 22N BETWEEN 50W-62W WITHIN THE AREA
OF LOW-LEVEL MOISTURE CONVERGENCE AND MIDDLE TO UPPER LEVEL
DIFFLUENCE. SCATTERED SHOWERS AND ISOLATED TSTMS ARE OVER
ADJACENT WATERS OF NE HISPANIOLA. THE REMAINDER SW NORTH ATLC IS
UNDER THE INFLUENCE OF A WEAK SURFACE RIDGE ANCHORED BY A 1015
MB HIGH CENTERED OVER THE NORTHERN BAHAMAS NEAR 26N77W. ACROSS
THE CENTRAL ATLC...A SURFACE RIDGE EXTENDS AN AXIS SOUTHWARD TO
18N. ISOLATED SHOWERS ARE WITHIN THIS RIDGE FROM 24N-28N BETWEEN
34W-42W. A MIDDLE TO UPPER LEVEL LOW IS CENTERED NEAR 33N28W
THAT SUPPORTS A 1003 MB SURFACE LOW CENTERED NEAR 33N25W. AN
OCCLUDED FRONT EXTENDS EAST-SOUTHEAST FROM THE LOW CENTER TO
29N14W. FROM THERE A COLD FRONT EXTENDS SW TO INLAND N AFRICA
WHILE A WARM FRONT EXTENDS SE FARTHER EAST INLAND.

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

$$
NR