000
AXNT20 KNHC 182351
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
705 PM EST FRI JAN 18 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 2345 UTC.

...ITCZ/MONSOON TROUGH...
THE MONSOON TROUGH PASSES THROUGH SOUTHERN COASTAL LIBERIA NEAR 
4N7W TO 3N15W. THE ITCZ CONTINUES FROM 3N15W TO 3N26W TO THE 
EQUATOR ALONG 39W. WIDELY SCATTERED MODERATE TO STRONG 
CONVECTION IS WITHIN 100 NM ALONG THE ITCZ BETWEEN 16W AND 31W. 
SCATTERED SHOWERS ARE SOUTH OF THE EQUATOR FROM 2S TO 4S BETWEEN 
23W AND 27W. 

...DISCUSSION...

THE GULF OF MEXICO...
NORTHEASTERLY WINDS OF 10-15 KT SPREAD OVER MOST OF THE GULF TONIGHT. 
STRONGER WINDS OF 20 KT ARE NE OF THE GULF EAST OF 90W NORTH OF 
25N. BROKEN TO OVERCAST STRATIFORM CLOUDINESS COVERS THE GULF 
SOUTH OF 28N.  SCATTERED SHOWERS ARE POSSIBLE ACROSS THIS REGION 
BEING SUPPORTED BY MOISTURE BEING ADVECTED FROM THE EAST PACIFIC 
AS INDICATED IN THE WATER VAPOR IMAGERY. EXCEPT FOR A REDUCTION 
IN WIND SPEED IN THE NE GULF EXPECT LITTLE CHANGES WITHIN THE 
NEXT 24 HOURS. 

THE CARIBBEAN SEA...
WEAK PRESSURE GRADIENT AND EASTERLY TRADE WINDS OF 10-15 KT 
SPREAD OVER THE EASTERN AND CENTRAL CARIBBEAN. MIDDLE TO UPPER 
LEVEL RIDGING WITH DRY AIR SUBSIDENCE COVERS THE ABOVE SPECIFIED 
REGION PROVIDING FAIR WEATHER CONDITIONS. IN THE SOUTHERN 
CARIBBEAN WHERE THE PRESSURE GRADIENT TIGHTENS...STRONGER 
NORTHEASTERLY WINDS OF MAINLY 20 KT DOMINATE. OVER THE WESTERN 
CARIBBEAN AND AS OF 2100 UTC...A COLD FRONT HAS TRANSITIONED TO 
A STATIONARY FRONT EXTENDING FROM SOUTHERN CENTRAL CUBA NEAR 
21N79W TO 19N83W TO THE NORTHERN COAST OF HONDURAS NEAR 15N86W. 
BROKEN TO OVERCAST SKIES ARE WEST AND EAST OF THE FRONTAL 
BOUNDARY AND THE IR SATELLITE IMAGERY CLOUD TOP TEMPERATURE 
SCHEME INDICATES SCATTERED SHOWERS ACROSS THIS REGION.  THE 
STATIONARY FRONT AND ASSOCIATED PRECIPITATION ARE BEING 
SUPPORTED BY A MIDDLE TO UPPER LEVEL TROUGH THAT EXTENDS FROM 
THE GULF OF TEHUANTEPEC IN THE EAST PACIFIC TO THE COAST OF 
ECUADOR. WITHIN 24 HOURS...EXCEPT BY THE DISSIPATION OF THE 
STATIONARY FRONT EXPECT LITTLE CHANGE. 

THE ATLANTIC OCEAN...
IN THE WEST ATLC...A COLD FRONT EXTENDS ALONG 30N68W 26N71W 
TO THE NORTH CENTRAL COAST OF CUBA NEAR 22N77W. BROKEN SKIES ARE 
IN THE VICINITY OF THE FRONT AND ISOLATED SHOWERS ARE POSSIBLE. 
A GALE WARNING IS IN EFFECT FOR THE AREA WEST OF THE COLD FRONT 
N OF 28N WHERE WIND BLOWS FROM THE NE AT 20-30 KT. IN THE 
CENTRAL ATLC...A SURFACE TROUGH REMNANT FROM A LOW EXTENDS ALONG 
28N43W 23N45W 19N45W WITH NO CONVECTIVE PRECIPITATION ASSOCIATED 
TO IT. IN THE EAST ATLC...WEAK RIDGING FROM A 1025 MB HIGH NEAR 
32N37W IS TO THE N OF 20N. WIDESPREAD MODERATE TO ISOLATED 
STRONG CONVECTION IS TO THE SE OF THE SURFACE TROUGH FROM 14N TO 
21W BETWEEN 38W AND 43W. THIS CONVECTION IS BEING SUPPORTED BY A 
MIDDLE TO UPPER LEVEL LOW CENTERED NEAR 16N42W. SCATTERED 
SHOWERS ARE FROM 6N TO 26N EAST OF 40W BEING SUPPORTED BY THE 
CONTINUATION OF MOISTURE ADVECTION FROM SOUTH OF THE EQUATOR.  

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

$$
NR