000
AXNT20 KNHC 132351
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
705 PM EST SUN JAN 13 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 ITCZ EXTENDS FROM THE COAST OF GUINEA NEAR 10N15W CONTINUING 
ALONG 6N21W 4N30W 5N42W 2N50W. SCATTERED MODERATE/ISOLATED 
STRONG CONVECTION IS WITHIN 120 NM EITHER SIDE OF THE AXIS 
BETWEEN 25W-48W.   

...DISCUSSION...

THE GULF OF MEXICO...
AS OF 2100 UTC...A COLD FRONT IS PUSHING THROUGH THE NW GULF OF 
MEXICO EXTENDING FROM SE LOUISIANA NEAR 29N91W TO THE SE COAST 
OF MEXICO ALONG 26N94W 20N97W 22N100W. STRONG NORTH TO NORTHWEST 
WINDS ARE WEST OF THE FRONT RANGING FROM 20-25 KT. SOUTHEAST TO 
SOUTH WINDS OF 15-20 KT ARE OBSERVED EAST OF THE FRONT. 
SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE UP TO 90 NM WEST OF 
THE FRONT WITH OVERCAST SKIES CONTINUING TO THE TEXAS COAST AND 
SLIGHTLY INLAND. THE FRONT IS SUPPORTED BY A SHORTWAVE TROUGH 
OVER LOUISIANA/MISSISSIPPI...WHICH IS MOVING AROUND A LONGWAVE 
TROUGH COVERING MUCH OF THE WESTERN CONUS. UPPER LEVEL RIDGING 
COVERS THE REMAINDER OF THE BASIN SUPPORTING A SURFACE RIDGE 
ANCHORED BY A 1023 MB HIGH EAST OF FLORIDA NEAR 30N77W. THE 
RIDGE IS SUPPORTING FAIR BUT WINDY CONDITIONS ACROSS THE CENTRAL 
AND EASTERN GULF. THE FRONT IS EXPECTED TO SLOWLY MOVE EASTWARD 
OVER THE NEXT 24 HOURS BEFORE BECOMING STATIONARY THROUGH THE 
EARLY PART OF THE WEEK.

THE CARIBBEAN SEA...
MOSTLY FAIR CONDITIONS ARE ACROSS THE GULF OF MEXICO DUE TO DRY 
AIR ALOFT AROUND AN UPPER LEVEL RIDGE OVER THE NW AND EASTERN 
CARIBBEAN...AND AROUND AN UPPER LEVEL TROUGH EXTENDING FROM 
EASTERN CUBA TO COSTA RICA. THE UPPER TROUGH DOES NOT APPEAR TO 
BE CAUSING ANY ACTIVE WEATHER IN THE BASIN AT THIS TIME. AT THE 
SURFACE...SURFACE RIDGING TO THE NORTH IS MAINTAINING TRADEWIND 
FLOW OF 15-20 KT. A FEW LOW-LEVEL ISOLATED SHOWER ARE EMBEDDED 
WITHIN THE TRADEWIND FLOW. LITTLE CHANGE IS EXPECTED OVER THE 
NEXT 24 HOURS

THE ATLANTIC OCEAN...
AN UPPER LEVEL RIDGE OVER THE EASTERN GULF OF MEXICO POURS OVER 
INTO THE WEST ATLC SUPPORTING A 1023 MB HIGH NEAR 30N77W...WHICH 
IS PROVIDING MOSTLY FAIR CONDITIONS ACROSS THE WEST ATLC. 
HOWEVER...A WEAK UPPER LEVEL LOW NEAR 25N76W SUPPORTS A SURFACE 
TROUGH THAT EXTENDS INTO THE RIDGE ALONG 30N64W 29N68W 30N73W. 
THE UPPER TROUGH IS EMBEDDED WITH DRY AIR...SO NO SHOWER 
ACTIVITY IS NOTED NEAR THE SURFACE TROUGH. ACROSS THE CENTRAL 
ATLC...A DEEP LAYERED LOW PRESSURE SYSTEM DOMINATES PROVIDING 
SEVERAL ENERGY SURGES ACROSS THE AREA. FARTHEST EAST...A 
STATIONARY FRONT ENTERS THE AREA NEAR 32N32W AND CONTINUES ALONG 
24N38W 16N50W. SCATTERED SHOWERS/POSSIBLE THUNDERSTORMS ARE 
WITHIN 200 NM WEST OF THE AXIS NORTH OF 25W. A SECOND SURGE IS 
BRING ISOLATED SHOWERS NORTH OF 28N BETWEEN 44W-54W. GALE FORCE 
WINDS ARE ALSO NOTED IN THE AREA NORTH OF 29N BETWEEN 50W-55W. 
THE REMAINDER OF THE BASIN IS COVERED BY SURFACE RIDGING 
EXTENDING FROM A 1033 MB HIGH WELL NORTH OF THE DISCUSSION AREA 
NEAR 46N20W. THE RIDGE IS SUPPORTED BY AN UPPER LEVEL RIDGE 
ALONG 24W. 

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

$$
WALTON