000
AXNT20 KNHC 162357
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
705 PM EST WED JAN 16 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 EXTENDS FROM THE AFRICAN COAST NEAR 06N11W TO 
06N16W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 
06N16W TO 04N20W 04N30W 03N40W TO MARAPANIM BRAZIL. ISOLATED 
MODERATE CONVECTION IS FROM THE EQUATOR TO 8N BETWEEN 10W-35W. 
SCATTERED SHOWERS ARE FROM 02N-06N BETWEEN 36W AND 42W.

...DISCUSSION...

GULF OF MEXICO...
A COLD FRONT EXTENDS FROM PANAMA CITY FLORIDA THEN SOUTHWESTWARD 
TO 26N88W 22N90W TO COMALCALCO MEXICO. SCATTERED SHOWERS ARE 
POSSIBLE WITHIN 80 NM OF THE FRONT. RETURN FLOW OF 5-15 KT IS TO 
THE EAST OF THE COLD FRONT. GALE FORCE WINDS ARE TO THE WEST OF 
THE FRONT. BY LATE THURSDAY THE FRONT WILL EXIT THE REGION WHILE 
NORTHERLY AND NORTHWESTERLY WIND OF 20-30 KT SPREADS ACROSS THE 
BASIN. 

CARIBBEAN SEA...
A WEAK UPPER LEVEL LOW OVER THE NW CARIBBEAN NEAR 20N85W STARTS 
TO MERGE INTO A BROAD AND STRONG RIDGE THAT COVERS THE GULF OF 
MEXICO...WEST ATLC AND PART OF THE CENTRAL ATLC. A WEAK UPPER 
LEVEL RIDGE COVERS THE REMAINDER OF THE CARIBBEAN. WATER VAPOR 
IMAGERY DEPICTS VERY DRY AIR ALOFT OVER THE ENTIRE BASIN WHICH 
IS KEEPING FAIR WEATHER CONDITIONS. EASTERLY TRADE WINDS IN THE 
RANGE OF 10 TO 20 KT SPREAD OVER ALMOST THE ENTIRE REGION AND 
ARE EXPECTED TO PERSIST THROUGH LATE THURSDAY IN THE EASTERN AND 
CENTRAL CARIBBEAN. BY LATE THURSDAY AND IN THE WESTERN 
CARIBBEAN...WINDS WILL SHIFT TO NORTHERLY WINDS OF 5-15 KT AS 
THE COLD FRONT IN THE GULF ENTERS INTO THE FLORIDA PENINSULA.

ATLANTIC OCEAN...
IN THE WEST ATLC...SURFACE RIDGING FROM A 1023 MB HIGH IS BEING 
SUPPORTED BY AN UPPER LEVEL STRONG ANTICYCLONE CENTERED NEAR 
29N66W. WATER VAPOR IMAGERY INDICATE MODERATE DRY AIR FROM ALOFT 
SUBSIDING OVER THE REGION ALLOWING FAIR WEATHER CONDITIONS. 
FURTHER EAST OVER THE CENTRAL ATLC A SURFACE 1007 MB LOW IS NEAR 
28N40W. A SURFACE TROUGH AXIS EXTENDS FROM THE LOW SOUTHWESTWARD 
TO 24N42W 21N44W. A DYING STATIONARY FRONT IS ANALYZED EAST OF 
THE LOW FROM 30N36W TO 25N36W TO 20N41W. BOTH THE LOW AND THE 
FRONTAL BOUNDARY ARE BEING SUPPORTED BY A MIDDLE TO UPPER LEVEL 
CUT-OFF LOW CENTERED NEAR 27N38W. WIDESPREAD MODERATE CONVECTION 
IS WITHIN 170 NM EAST OF THE DYING STATIONARY FRONT. SCATTERED 
SHOWERS ARE BOUNDED BY THE SURFACE TROUGH AND THE DYING 
STATIONARY FRONT NORTH OF 20N. THE EASTERN ATLC IS BEING 
INFLUENCED BY WEAK SURFACE RIDGING FROM A 1028 MB HIGH ANCHORED 
TO THE NE OF THE MADEIRA ISLANDS NEAR 34N14W. HOWEVER... 
DIFFLUENCE DUE TO THE PREVIOUSLY MENTIONED UPPER LEVEL LOW AND 
MOISTURE BEING ADVECTED FROM SOUTH OF THE EQUATOR IS GENERATING 
AN AREA OF ISOLATED SHOWERS FROM 11N-27N BETWEEN 17W-37W.

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

$$
RAMOS