000 AXNT20 KNHC 191803 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 105 PM EST TUE DEC 19 2006 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA... CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA... NORTHEASTERN SECTIONS OF SOUTH AMERICA...AND THE 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1715 UTC. ...THE ITCZ... 6N9W 6N20W 5N30W 4N40W 4N49W INTO NORTHEASTERN BRAZIL/SOUTHERN FRENCH GUIANA NEAR 2N53W. WIDELY SCATTERED MODERATE SHOWERS TO ISOLATED STRONG THUNDERSTORMS ARE SOUTH OF 3N BETWEEN THE PRIME MERIDIAN AND 10W. ISOLATED MODERATE SHOWERS AND POSSIBLE THUNDERSTORMS ARE FROM THE EQUATOR TO 10N BETWEEN 35W AND 51W. ...DISCUSSION... THE GULF OF MEXICO AND THE ATLANTIC OCEAN NORTH OF 20N WEST OF 60W... A DEEP LAYER CYCLONIC CIRCULATION CENTER IS ALONG THE SOUTHEASTERN NEVADA/NORTHWESTERN ARIZONA BORDER. UPPER LEVEL CYCLONIC FLOW COVERS ARIZONA AND NEW MEXICO...TO THE FAR WEST TEXAS AND THE TEXAS PANHANDLE. UPPER LEVEL ANTICYCLONIC FLOW IS WITHIN 240 NM ON EITHER SIDE OF 18N107W FROM THE EASTERN PACIFIC OCEAN TO 26N102W BEYOND 31N99W IN CENTRAL TEXAS. A NORTHWESTERN 1019 MB SURFACE LOW PRESSURE CENTER IS NEAR 26N95W. A TROUGH GOES FROM THE TEXAS COAST NEAR 29N94W TO THE LOW CENTER TO 24N95W. SHOWERS ARE POSSIBLE WITHIN 15 TO 30 NM ON EITHER SIDE OF 24N97W 27N95W 28N95W 29N94W. LOW CLOUDS WITH CLOUD TOPS TO 40000 FEET AND POSSIBLE SHOWERS ARE WITHIN 15 NM ON EITHER SIDE OF 24N82W 23N84W 22N87W... FROM THE YUCATAN PENINSULA TO 26N BETWEEN 88W AND 90W...AND FROM 25N TO THE LOUISIANA/TEXAS COAST WEST OF 90W. BROKEN TO OVERCAST MULTILAYERED CLOUDS WITH TOPS TO 35000 FEET AND 40000 FEET SOUTH OF 22N WEST OF 90W AND THE YUCATAN PENINSULA. UPPER LEVEL NORTHWESTERLY WIND FLOW MOVES FROM MEXICO TOWARD 90W. MIDDLE LEVEL CYCLONIC FLOW ACROSS PARTS OF FLORIDA AND IN THE EASTERN GULF WATERS IS RELATED TO THE MIDDLE LEVEL 22N72W CYCLONIC CIRCULATION CENTER ON TOP OF THE TURKS AND CAICOS ISLANDS. UPPER LEVEL NORTHWESTERLY FLOW ALSO GOES FROM THE U.S.A. GULF COAST STATES TOWARD THE GULF WATERS AND FLORIDA...BEFORE COMBINING WITH THE CYCLONIC FLOW FROM THE 22N72W CYCLONIC CENTER. BROKEN TO OVERCAST MULTILAYERED CLOUDS ARE FROM 21N TO 26N BETWEEN 55W AND 78W. ISOLATED MODERATE SHOWERS FROM 21N TO 24N BETWEEN 58W AND 74W. THIS PRECIPITATION IS RELATED TO WHATEVER REMAINS...A SHEAR AXIS/WEAK SURFACE TO LOW LEVEL TROUGH...OF AN OLD COLD FRONT...WHAT NOW IS IN THE CENTRAL ATLANTIC OCEAN. THE CARIBBEAN SEA... A MIDDLE TO UPPER LEVEL TROUGH ENTERS THE AREA FROM A 22N72W TURKS AND CAICOS CYCLONIC CIRCULATION CENTER...TO 15N78W IN THE WEST CENTRAL CARIBBEAN SEA...TO THE SOUTHWESTERN CORNER OF THE AREA. MIDDLE TO UPPER LEVEL DRY AIR ABOUNDS WEST OF 70W...EXCEPT FOR A BIT OF PRECIPITATION NORTH OF 14N BETWEEN 70W AND 73W. ISOLATED MODERATE SHOWERS TO LOCALLY STRONG THUNDERSTORMS ARE FROM 14N TO 18N BETWEEN 68W AND 73W. UPPER LEVEL ANTICYCLONIC FLOW COVERS THE ATLANTIC WATERS AND CARIBBEAN SEA SOUTH OF 20N BETWEEN 30W AND 70W. THE ATLANTIC OCEAN... A CENTRAL ATLANTIC DEEP LAYER CYCLONIC CIRCULATION CENTER IS NEAR 29N31W. THE SURFACE 1013 MB LOW PRESSURE CENTER IS NEAR 30N33W. THE MIDDLE TO UPPER LEVEL TROUGH WITH THE 29N31W CENTER EXTENDS TO 19N35W. THE SURFACE TROUGH WITH THE 1013 MB LOW CENTER GOES FROM THE LOW TO 28N31W AND 25N33W. A DISSIPATING COLD FRONT PASSES THROUGH 30N37W FROM THE NORTH TO 26N40W AND 23N46W. THIS FRONT CONTINUES TO WEAKEN WITH TIME. WIDELY SCATTERED TO SCATTERED MODERATE SHOWERS/ISOLATED STRONG THUNDERSTORMS ARE FROM 24N TO 26N BETWEEN 27W AND 29W... AND FROM 27N TO 29N BETWEEN 27W AND 28W. OTHER SHOWERS ARE POSSIBLE NORTH OF 24N BETWEEN 25W AND 30W. SCATTERED MODERATE SHOWERS TO ISOLATED STRONG THUNDERSTORMS ARE AROUND THE 1013 MB LOW PRESSURE CENTER FROM 27N TO 31N BETWEEN 30W AND 35W. $$ MT