000
AXNT20 KNHC 111146
TWDAT 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL  
705 AM EST SAT DEC 11 2010

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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1115 UTC.

...ITCZ...
 
THE ITCZ AXIS IS CENTERED FROM GUINEA NEAR 10N14W ALONG 6N23W 
4N35W 3N52W. NUMEROUS MODERATE/SCATTERED STRONG CONVECTION IS 
FROM 4-13N BETWEEN 11W-21W...AND FROM 5N-9N BETWEEN 21W-30W.

...DISCUSSION...

GULF OF MEXICO...
THE GULF OF MEXICO REMAINS UNDER MOSTLY FAIR CONDITIONS THIS 
MORNING AS A DRY AIRMASS COVERS THE BASIN IN MAINLY WLY FLOW 
ALOFT. A SURFACE RIDGE EXTENDS FROM NE TO SW WITH LIGHT 
ANTI-CYCLONIC SURFACE FLOW AROUND IT. STRONGER SLY WINDS UP TO 
20 KTS ARE ALONG THE TEXAS COASTLINE. THESE WINDS WILL PERSIST 
AS A COLD FRONT PUSHES INTO THE NW GULF LATE TONIGHT AND EARLY 
SUNDAY. AREAS OF STRATOCUMULUS CLOUDS ARE NOTED ACROSS MUCH OF 
THE CENTRAL AND NW PORTIONS OF THE BASIN. EXPECT LITTLE CHANGE 
UNTIL THE AFOREMENTIONED FRONT APPROACHES THE TEXAS COAST.

CARIBBEAN SEA...
DRY AIR AND SUBSIDENCE IN MAINLY SWLY FLOW ALOFT COVERS THE NW 
CARIBBEAN MAINTAINING FAIR CONDITIONS BESIDES A FEW PATCHES OF 
LOW CLOUDS. SHOWER ACTIVITY HAS BEGUN TO DIE DOWN AS THE UPPER 
LEVEL JET PREVIOUSLY ACROSS THE CENTRAL CARIBBEAN HAS LIFTED N. 
HOWEVER...AN AREA OF ENHANCED MOISTURE STILL REMAINS FROM PANAMA 
TO HISPANIOLA. SURFACE TROUGHING S OF HISPANIOLA AS WELL A SHEAR 
AXIS EXTENDING FROM 16N75W TO A 1009 MB LOW OVER PANAMA NEAR 
9N78W CONTINUES TO SUPPORT ISOLATED SHOWERS WITHIN 150 NM NW OF 
THE BOUNDARY. THE AXIS SEPARATES STRONG NLY FLOW TO THE W...AND 
TRADEWIND ELY FLOW TO THE E. THE REMAINDER OF THE BASIN IS 
EXPERIENCING MOSTLY FAIR CONDITIONS UNDER AN UPPER LEVEL RIDGE 
CENTERED OVER NE VENEZUELA. EXPECT LITTLE CHANGE OVER THE NEXT 
24 HRS. 


ATLANTIC OCEAN...
BROAD UPPER LEVEL TROUGHING OVER THE FAR WRN ATLC IS SUPPORTING 
A SERIES OF FRONTAL BOUNDARIES AND SURFACE LOW PRESSURE SYSTEMS 
ACROSS THE W ATLC. A 1014 MB LOW IS CENTERED N OF THE SE BAHAMAS 
NEAR 26N73W. NELY WINDS UP TO 25 KTS ARE NW OF THE CENTER. A 
SURFACE TROUGH EXTENDS THROUGH THE LOW CENTER ALONG 27N68W 
26N73W 24N76W 27N79W 32N80W. ISOLATED SHOWERS ARE WITHIN 75 NM 
OF THE TROUGH AXIS. A 1012 MB LOW IS CENTERED N OF THE MONA 
PASSAGE NEAR 24N66W. A SURFACE TROUGH EXTENDS TO THE S ALONG 
19N69W AND S OF HISPANIOLA TO NEAR 16N75W. ISOLATED SHOWERS ARE 
WITHIN 90 NM EITHER SIDE OF THE AXIS. A DISSIPATING STATIONARY 
BOUNDARY EXTENDS N OF THE LOW CENTER AND OUT OF THE DISCUSSION 
AREA ALONG 27N63W 29N55W 32N49W. THIS SYSTEM LIES UNDERNEATH AN 
AREA OF DIFFLUENCE ALOFT BETWEEN THE UPPER TROUGH TO THE W AND 
AN UPPER LEVEL RIDGE EXTENDING FROM E OF THE LESSER ANTILLES 
CONTINUING NE TO THE AZORES ISLANDS. THE COMBINATION OF UPPER 
LEVEL DIFFLUENCE AND SURFACE CONVERGENCE IS SUPPORTING SCATTERED 
SHOWERS/POSSIBLE THUNDERSTORMS N OF 25N BETWEEN 53W-67W. FARTHER 
E...SURFACE RIDGING DOMINATES ANCHORED BY A 1019 MB HIGH NEAR 
28N41W PROVIDING MOSTLY FAIR CONDITIONS. AN OCCLUDED LOW 
PRESSURE SYSTEM IS N OF THE DISCUSSION AREA NEAR THE AZORES 
ISLANDS CAUSING CYCLONIC SURFACE FLOW ACROSS THE FAR E ATLC N OF 
27N. A SURFACE TROUGH ENTERS THE AREA NEAR 32N20W TO 27N25W 
DEPICTING THE LOCATION OF THE WIND SHIFT. THIS SYSTEM IS 
SUPPORTED BY AN UPPER LEVEL TROUGH EXTENDING FROM 6N47W TO E OF 
THE CAPE VERDE ISLANDS AND NWD TO THE AZORES. THERE IS NO SHOWER 
ACTIVITY ASSOCIATED WITH THIS SYSTEM. 

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

$$
WALTON