000
AXNT20 KNHC 161803
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
105 PM EST MON JAN 16 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1700 UTC.

...ITCZ/MONSOON TROUGH...

THE MONSOON TROUGH EXTENDS S OF NW AFRICA ALONG 4N AND THE PRIME 
MERIDIAN TO 2N8W. THE ITCZ CONTINUES FROM 2N8W ALONG 4N24W 1N36W 
1N49W. A SMALL AREA OF SCATTERED MODERATE/STRONG CONVECTION IS S 
OF THE AXIS FROM 1N-2N BETWEEN 3W-5W. NO DEEP CONVECTION IS 
NOTED ELSEWHERE.   

...DISCUSSION...

GULF OF MEXICO...
SURFACE RIDGING AROUND A 1037 MB HIGH OVER N CAROLINA CONTINUES 
TO PROVIDE MOSTLY FAIR WEATHER ACROSS THE GULF OF MEXICO TODAY. 
SURFACE WIND SPEEDS HAVE INCREASED SINCE YESTERDAY AS THE RIDGE 
HAS SHIFTED NE. CURRENTLY SE-S WINDS ARE ACROSS MUCH OF THE 
BASIN OF MOSTLY 15-20 KTS WITH WINDS UP TO 25 KTS S OF 25N. 
SKIES ARE MOSTLY CLEAR WITH SOME AREAS OF LOW CLOUDS ALONG THE 
MEXICAN COAST IN THE BAY OF CAMPECHE WITH POSSIBLE ISOLATED 
SHOWERS. ALOFT...MOSTLY ZONAL WLY FLOW COVERS THE AREA. EXPECT 
THE SURFACE RETURN FLOW TO CONTINUE ACROSS THE BASIN THROUGH 
TUES NIGHT/EARLY WED WHEN A COLD FRONT ENTERS THE NW CORNER. 
FAIR WEATHER IS EXPECTED UNTIL THE PASSAGE OF THE FRONT WHICH 
WILL LIKELY BRING SHOWERS/THUNDERSTORMS.

CARIBBEAN SEA...
THE TAIL END OF A FRONTAL BOUNDARY...STILL DISSIPATING AND 
STATIONARY...EXTENDS ACROSS FAR ERN CUBA ALONG 21N75W TO 19N81W. 
POSSIBLE ISOLATED SHOWERS ARE WITHIN 75 NM N OF THE AXIS OVER 
CUBA. THE REMAINDER OF THE BASIN HAS GENERALLY FAIR WEATHER WITH 
MOSTLY CLEAR SKIES DUE TO DRY AIR ALOFT AROUND AN UPPER LEVEL 
RIDGE COVERING THE BASIN. PATCHES OF LOW-LEVEL CLOUDS AND 
POSSIBLE EMBEDDED ISOLATED SHOWERS ARE OVER MUCH OF THE AREA 
WITHIN THE NE-E TRADEWIND FLOW. WINDS OF 20-25 KTS ARE ACROSS 
THE BASIN REACHING 30 KTS NEAR THE COAST OF COLOMBIA. EXPECT THE 
FRONTAL BOUNDARY TO DISSIPATE COMPLETELY SOON WITH FAIR 
CONDITIONS REMAINING ELSEWHERE. 

ATLANTIC OCEAN...
SURFACE HIGH PRESSURE IS BEGINNING TO BUILD OVER THE FAR W ATLC 
AROUND A 1037 MB HIGH OVER N CAROLINA. THE RIDGE IS SUPPORTED BY 
AN UPPER LEVEL RIDGE EXTENDING OVER THE CARIBBEAN AND ERN CONUS. 
AN UPPER LEVEL TROUGH TO THE W ALONG 57W SUPPORTS A COLD FRONT 
ENTERING THE DISCUSSION AREA NEAR 32N51W CONTINUING ALONG 25N60W 
TO ERN CUBA NEAR 21N75W. SCATTERED SHOWERS ARE WITHIN 120 NM 
AHEAD OF THE FRONT WITH ISOLATED THUNDERSTORMS N OF 28N. THE 
REMAINDER OF THE BASIN IS DOMINATED BY A BROAD SURFACE RIDGE 
ANCHORED BY 1031 MB HIGH S OF THE AZORES ISLANDS NEAR 33N28W 
PROVIDING MOSTLY FAIR WEATHER. THE RIDGE IS SUPPORTED BY AN 
UPPER LEVEL RIDGE COVERING THE NE ATLC CENTERED NEAR 36N26W. A 
CUT-OFF UPPER LEVEL LOW IS TO THE S NEAR 24N33W SUPPORTING AN 
AREA OF HIGH CLOUDS RANGING FROM THE ITCZ NEAR 5N48W TO NW 
AFRICA NEAR 20N17W. EXPECT THE FRONT IN THE CENTRAL ATLC TO 
CONTINUE TO PUSH EWD. 

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

$$
WALTON