000
AXNT20 KNHC 162325
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL  
705 PM EST SUN JAN 16 2011

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...METEOROLOGICAL ANALYSIS...WEATHER OBSERVATIONS...AND 
RADAR.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
2300 UTC.

...THE ITCZ...

ITCZ AXIS EXTENDS FROM GUINEA NEAR 11N12W ALONG 2N26W 1N40W 
CROSSING THE EQUATOR NEAR 43W TO 2S50W. ISOLATED MODERATE 
CONVECTING IS WITHIN 90 NM EITHER SIDE OF THE AXIS BETWEEN 
25W-29W. SCATTERED MODERATE CONVECTION IS WITHIN 300 NM S OF THE 
AXIS BETWEEN 29W-41W. SCATTERED MODERATE/STRONG CONVECTION IS 
WITHIN 75 NM N...150 NM S OF THE AXIS BETWEEN 41W-50W.  

...DISCUSSION...

THE GULF OF MEXICO...
MAINLY SWLY FLOW ALOFT COVERS THE GULF OF MEXICO BETWEEN A BROAD 
UPPER RIDGE ACROSS THE W ATLC...AND A SHORTWAVE UPPER TROUGH 
ACROSS ERN TEXAS. THE SHORTWAVE UPPER TROUGH SUPPORTS A 
WEAKENING COLD FRONT THAT IS JUST OFF THE TEXAS 
COASTLINE...ALONG WITH WIDESPREAD SHOWERS ACROSS FAR ERN 
TEXAS...MAJORITY OF LOUISIANA...AND PORTIONS OF SRN ARKANSAS AND 
WRN MISSISSIPPI. THE SHOWERS ALSO SPREAD INTO THE NW GULF N OF 
24N W OF 92W. THIS WEAK LOW PRESSURE SYSTEM IS FORECAST TO MOVE 
FARTHER INTO THE NW GULF WITH THE FRONT CONTINUING TO DISSIPATE. 
SEVERAL FRONTAL BOUNDARIES ARE FORECAST TO MOVE INTO THE GULF 
WATERS THROUGHOUT THE NEXT WEEK. ELSEWHERE...A SURFACE TROUGH 
EXTENDS FROM 25N87W TO THE YUCATAN PENINSULA FLARING UP AN AREA 
OF SCATTERED SHOWERS FROM 24N-27N BETWEEN 83W-89W. THE REMAINDER 
OF THE BASIN IS UNDER MOSTLY CLEAR SKIES.  
 
THE CARIBBEAN SEA...
LITTLE ACTIVE WEATHER IS NOTED ACROSS THE CARIBBEAN AS A MOSTLY 
DRY AIR MASS COVERS THE BASIN WITH MAINLY SWLY FLOW ALOFT AROUND 
A BROAD UPPER LEVEL RIDGE CENTERED N OF ERN BRAZIL. PATCHES OF 
LOW CLOUDS AND POSSIBLE ISOLATED SHOWERS ARE ACROSS THE NW 
PORTION OF THE BASIN FROM 13N-18N BETWEEN 79W-83W...AND FROM 
17N-20N BETWEEN 84W-87W. MODERATE TO FRESH NELY TRADEWINDS ARE 
ACROSS THE ERN HALF OF THE AREA BROADLY TURNING AROUND WEAK LOW 
PRESSURE ACROSS NRN COLOMBIA. EXPECT LITTLE CHANGE OVER THE NEXT 
24 HOURS. 

THE ATLANTIC OCEAN...
A WEAKENING COLD FRONT CLIPS THE NW PORTION OF THE DISCUSSION 
AREA NEAR 31N74W TO 30N78W CONTINUING AS A SURFACE TROUGH TO THE 
NE BAHAMAS NEAR 27N79W. ISOLATED SHOWERS ARE WITHIN 45 NM EITHER 
SIDE OF THE AXIS. THE SYSTEM HAS LITTLE UPPER LEVEL SUPPORT AS A 
BROAD UPPER RIDGE COVERS MUCH OF THE WRN ATLC EXTENDING FROM N 
OF ERN BRAZIL. THIS UPPER RIDGE SUPPORTS A BROAD SURFACE RIDGE 
ANCHORED BY A 1023 MB HIGH NEAR 32N50W. HOWEVER...A SECOND 
FRONTAL BOUNDARY BISECTS THE RIDGE. THE SYSTEM CONSISTS OF A 
STATIONARY FRONT EXTENDING FROM 32N32W TO NEAR 27N62W LIFTING N 
AS A WARM FRONT ALONG 29N66W TO 25N71W DISSIPATING TO 22N75W. 
SCATTERED SHOWERS ARE WITHIN 150 NM N OF THE BOUNDARY BETWEEN 
51W-68W...AND S OF THE BOUNDARY BETWEEN 59W-64W. A SURFACE HIGH 
IS ALSO TO THE SE OF THE FRONT NEAR 28N30W MAINTAINING FAIR 
CONDITIONS ACROSS THE CENTRAL AND ERN ATLC S OF THE FRONTAL 
BOUNDARY. ALOFT...BESIDES THE DOMINANT BROAD UPPER RIDGE...A 
WEAK UPPER TROUGH EXTENDS ACROSS THE CAPE VERDE ISLANDS. 

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

$$
WALTON