000
AXNT20 KNHC 201132
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
705 AM EST SUN JAN 20 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 1045 UTC.

...ITCZ/MONSOON TROUGH...
THE MONSOON TROUGH EXTENDS THROUGH CENTRAL SIERRA LEONE INTO THE 
EASTERN TROPICAL ATLC ALONG 8N13W 6N18W. THE ITCZ BEGINS AT 
6N18W AND CONTINUES TO 1N33W. SCATTERED MODERATE/ISOLATED STRONG 
CONVECTION IS FROM EQ-4N BETWEEN 28W-31W. 

...DISCUSSION...

THE GULF OF MEXICO...
WEAK SURFACE RIDGING COVERS THE MAJORITY OF THE GULF OF MEXICO 
THIS MORNING AROUND A PAIR OF 1025 MB HIGHS OVER CENTRAL ALABAMA 
AND EASTERN TEXAS. THIS PATTERN IS PROVIDING LIGHT ANTI-CYCLONIC 
WINDS OF 10-15 KT ACROSS MUCH OF THE AREA. A STATIONARY FRONT 
STILL REMAINS JUST SE OF FLORIDA EXTENDING THROUGH THE FLORIDA 
STRAITS PROVIDING SOME MOIST CONDITIONS ACROSS SOUTH FLORIDA AND 
THE SE GULF WHERE A FEW WIDELY ISOLATED SHOWERS ARE NOTED. A 
WEAK SURFACE TROUGH WAS ADDED WEST OF FLORIDA ALONG 27N83W TO 
23N85W BASED ON SATELLITE IMAGERY AND ASCAT SCATTEROMETER DATA 
FROM OVERNIGHT. PATCHES OF LOW-LEVEL CLOUDS COVER THE MAJORITY 
OF THE BASIN WITH POSSIBLE ISOLATED SHOWERS. ALOFT...MAINLY SW 
FLOW COVERS THE AREA BETWEEN A BROAD UPPER TROUGH COVERING MUCH 
OF THE CENTRAL AND EASTERN CONUS...AND AN UPPER LEVEL RIDGE 
ACROSS THE CARIBBEAN AND WEST ATLC. MOISTURE ASSOCIATED WITH THE 
STATIONARY FRONT WILL CONTINUE TO MOVE NORTH COVERING THE 
SOUTHERN GULF BEFORE BEING PUSHED SOUTH IN THE MIDDLE OF NEXT 
WEEK. 

THE CARIBBEAN SEA...
DRY AIR ALOFT AROUND A BROAD UPPER RIDGE COVERING THE CARIBBEAN 
IS HELPING PROVIDE MOSTLY FAIR CONDITIONS ACROSS THE BASIN. A 
FEW ISOLATED SHOWERS ARE NOTED OVER THE FAR WESTERN CARIBBEAN 
ASSOCIATED WITH SOME HIGHER MOISTURE. A FEW WIDELY ISOLATED 
SHOWERS ARE ELSEWHERE ACROSS THE BASIN EMBEDDED WITHIN 15-20 KT 
TRADEWIND FLOW. GALE FORCE WINDS ARE LOCATED IN A VERY SMALL 
AREA JUST NEAR THE COAST OF COLOMBIA. WINDS TO GALE FORCE WERE 
OBSERVED BY TWO DIFFERENT SHIPS IN THE VICINITY. THE AREA OF 
MOISTURE OVER THE WESTERN CARIBBEAN IS EXPECTED TO REMAIN THERE 
OVER THE NEXT SEVERAL DAYS.  

THE ATLANTIC OCEAN...
A BROAD UPPER LEVEL TROUGH OVER MUCH OF THE CONUS AND THE 
NORTHWEST ATLC SUPPORTS A STATIONARY FRONT THAT ENTERS THE 
DISCUSSION AREA NEAR 32N59W AND CONTINUES TOWARDS THE NW BAHAMAS 
ALONG 30N67W 27N73W 28N78W 24N81W. POSSIBLE ISOLATED SHOWERS 
EXTEND UP TO 200 NM NORTH OF THE AXIS. THE FRONT BISECTS A LARGE 
SURFACE RIDGE COVERING A GOOD PORTION OF THE ATLANTIC. A 1032 MB 
SURFACE HIGH IS CENTERED N OF THE FRONT NEAR 40N47W PROVIDING 
RIDGING OVER THE REMAINDER OF THE WEST ATLC. A 1027 MB HIGH NEAR 
32N44W IS S OF THE FRONT PROVIDING RIDGING OVER THE CENTRAL AND 
EASTERN ATLC. BOTH OF THE HIGH CENTERS ARE SUPPORTED ALOFT BY AN 
UPPER LEVEL RIDGE COVERING THE CARIBBEAN AND SW NORTH ATLC ALONG 
61W WITH AXIS CONTINUING NE TOWARD THE NE ATLC. AN UPPER LEVEL 
LOW COVERS THE EASTERN TROPICAL ATLC NEAR 20N38W SUPPORTING AN 
AREA OF SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 19N-24N 
BETWEEN 30W-36W.  

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

$$
WALTON