000
AXNT20 KNHC 191744
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
105 PM EST THU JAN 19 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 FROM THE SRN COAST OF SIERRA LEONE 
NEAR 7N12W TO 4N19W. THE ITCZ CONTINUES FROM 4N19W ALONG 2N33W 
2N43W 1N51W. SCATTERED MODERATE CONVECTION IS FROM 1S-4N BETWEEN 
25W-32W.
   

...DISCUSSION...

GULF OF MEXICO...
A WEAK FRONTAL SYSTEM IS ACROSS THE GULF OF MEXICO THIS 
AFTERNOON. THE ERN PORTION IS ANALYZED AS A COLD FRONT STILL 
MOVING SE ALONG 26N80W TO 25N87W...AS OF 1500 UTC...PLACING IT S 
OF LAKE OKEECHOBEE. THE FRONT THEN TRANSITIONS TO STATIONARY TO 
26N89W BECOMING WARM AND LIFTING N TO THE LOUISIANA COAST NEAR 
30N93W. MOSTLY DRY AIR ALOFT IN WNW FLOW AROUND AN UPPER LEVEL 
TROUGH OVER THE W ATLC IS INHIBITING SHOWER ACTIVITY ALONG THE 
FRONT AXIS. AN AREA OF SHOWERS IS NOTED IN RADAR IMAGERY AHEAD 
OF THE COLD FRONT OVER THE FLORIDA KEYS. SATELLITE IMAGERY 
INDICATES SOME PATCHES OF FOG IN THE NW GULF ALONG THE TEXAS AND 
LOUISIANA COASTLINES. THE REMAINDER OF THE BASIN IS UNDER MOSTLY 
CLEAR SKIES AND LIGHT WINDS. THE SURFACE FLOW IS MAINLY 
ANTI-CYCLONIC AROUND A SURFACE HIGH OVER GEORGIA. EXPECT THE WRN 
PORTION OF THE FRONT TO DISSIPATE AS THE HIGH PRESSURE TO THE N 
IMPACTS THE BASIN. THE ERN PORTION OF THE FRONT WILL CONTINUE TO 
MOVE E OF THE FLORIDA INTO THE W ATLC. 

CARIBBEAN SEA...
FAIR WEATHER IS ACROSS THE CARIBBEAN TODAY DUE TO DRY AIR ALOFT 
IN MOSTLY WLY FLOW. NE-E TRADEWIND FLOW OF 15-20 KTS IS ACROSS 
MUCH OF THE BASIN INCREASING IN SPEED TO 25 KTS NEAR THE COAST 
OF COLOMBIA. PATCHES OF LOW-LEVEL CLOUDS AND POSSIBLE ISOLATED 
SHOWERS ARE EMBEDDED WITHIN THE TRADEWIND FLOW. EXPECT LITTLE 
CHANGE OVER THE NEXT 24 HOURS. 

ATLANTIC OCEAN...
AN UPPER LEVEL TROUGH OVER THE ERN SEABOARD AND WRN ATLC ALONG 
70W SUPPORTS A COLD FRONT ENTERING THE DISCUSSION AREA NEAR 
32N69W CONTINUING TOWARDS SE FLORIDA NEAR 26N80W...AS OF 1500 
UTC. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE E OF THE FRONT 
N OF 27N BETWEEN 64W-71W. AN UPPER LEVEL RIDGE TO THE E ALONG 
54W SUPPORTS A 1032 MB SURFACE HIGH NEAR 36N44W WHICH IS 
PROVIDING MOSTLY FAIR WEATHER BETWEEN THE AFOREMENTIONED FRONT 
AND A SECOND STATIONARY FRONT IN THE CENTRAL/ERN ATLC. THE FRONT 
IS ALONG 32N35W TO 19N47W. A SURFACE TROUGH IS W OF THE FRONT 
ALONG 28N42W TO 24N46W. SCATTERED SHOWERS/POSSIBLE THUNDERSTORMS 
ARE WITHIN 200 NM OF THE FRONT AXIS AND WITHIN 100 NM OF THE 
SURFACE TROUGH AXIS. THE SYSTEM IS SUPPORTED BY AN UPPER LEVEL 
TROUGH ALONG 37N38W TO 19N51W. AN UPPER LEVEL RIDGE TO THE E 
CENTERED NEAR 36N17W SUPPORTS A SURFACE RIDGE AROUND A 1041 MB 
HIGH NEAR 42N14W WHICH IS PROVIDING FAIR CONDITIONS ACROSS THE 
REMAINDER OF THE E ATLC. EXPECT THE FRONT IN THE W ATLC TO 
CONTINUE TO MOVE EWD INTO THE CENTRAL ATLC OVER THE NEXT COUPLE 
OF DAYS. 

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

$$
WALTON