000 AXNT20 KNHC 181101 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 AM EST TUE DEC 18 2007 TROPICAL WEATHER DISCUSSION FOR NORTH AMERICA...CENTRAL AMERICA...THE GULF OF MEXICO...THE CARIBBEAN SEA...NORTHERN 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC ...THE ITCZ... ITCZ AXIS IS CENTERED ALONG 7N11W 5N17W 5N24W 3N38W 3N53W. SCATTERED MODERATE WITH EMBEDDED CLUSTERS OF ISOLATED STRONG CONVECTION ARE FROM 1N TO THE COAST OF SW AFRICA BETWEEN 3W-6W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 60 NM OF THE ITCZ AXIS FROM 26W-38W. AN AREA OF UPPER DIFFLUENCE COUPLED WITH TROPICAL MOISTURE IS GENERATING SCATTERED MODERATE/ISOLATED STRONG CONVECTION FROM 4N-8N BETWEEN 45W-49W. DISCUSSION... GULF OF MEXICO... ZONAL WESTERLY UPPER FLOW DOMINATES THE GULF THIS MORNING WITH A JETSTREAM OF WINDS ESTIMATED TO BE 80 TO 110 KT OVER THE N GULF AND THE SE US N OF 25N FROM TEXAS INTO THE W ATLC. A SURFACE RIDGE DOMINATES THE GULF ANCHORED OVER THE E US WITH A 1030 MB HIGH OVER SE ALABAMA. RETURN FLOW AROUND THIS SURFACE RIDGE IS BANKING LOW LEVEL CLOUDS WITH WIDELY ISOLATED SHOWERS OVER THE W AND CENTRAL GULF TO THE SIERRA MADRE MOUNTAINS LEAVING THE E GULF WITH CLEAR SKIES E OF 86W TO OVER FLORIDA. HIGH PRESSURE WILL REMAIN IN CONTROL OF THE GULF WITH THE NEXT FRONT MOVING IN LATE IN THE WEEK. CARIBBEAN SEA... BROAD UPPER RIDGE COVERS THE W CARIBBEAN W OF 75W WITH THE RIDGE AXIS EXTENDING FROM THE GULF OF HONDURAS ENE ACROSS HISPANIOLA INTO THE W/CENTRAL ATLC. AN UPPER TROUGH COVERS THE REMAINDER OF THE CARIBBEAN EXTENDING FROM THE VIRGIN ISLANDS TO OVER COLOMBIA. DRY STABLE AIR REIGNS OVER MOST OF THE CARIBBEAN EXCEPT W OF A NEAR STATIONARY FRONTAL BOUNDARY THAT EXTENDS ACROSS E CUBA NEAR 20N76W TO HONDURAS NEAR 15N85W. MOSTLY OVERCAST LOW CLOUDS WITH ISOLATED SHOWERS ARE W OF THE FRONT. THE REMAINDER OF THE CARIBBEAN HAS WIDELY SCATTERED LOW LEVEL CLOUDS BUT REMAINS RATHER TRANQUIL THIS MORNING. MODERATE/STRONG NE TO E WINDS DOMINATE THE CARIBBEAN. ATLANTIC OCEAN... THE DEEP LAYERED TROUGH THAT COVERS THE FAR NE US AND THE W ATLC W OF 62W WITH THE ASSOCIATED COLD FRONT ENTERING THE REGION NEAR 32N60W TO THE TURKS AND CAICOS BECOMING NEAR STATIONARY THEN CONTINUING INTO THE CARIBBEAN OVER CUBA NEAR 20N76W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE WITHIN 60 NM E OF THE FRONT N OF 26N WITH MOSTLY OVERCAST LOW CLOUDS WITH WIDELY ISOLATED SHOWERS WITHIN 150/200 NM W OF THE FRONT INTO THE CARIBBEAN. A JETSTREAM WITH WINDS ESTIMATED TO BE 80 TO 110 KT COVERS THE W ATLC N OF 24N W OF THE FRONT. AN UPPER RIDGE IN THE CARIBBEAN EXTENDS ACROSS HISPANIOLA NEAR 20N71W TO 26N59W WITH A SECOND UPPER HIGH CENTERED IN THE CENTRAL ATLC NEAR 30N48W. A DEEP LAYERED TROUGH IS OVER E ATLC N OF 20N E OF 30W WITH THE ASSOCIATED COLD FRONT ENTERING THE REGION NEAR 32N16W EXTENDING ALONG 27N24W TO 25N31W THEN DISSIPATING TO NEAR 25N37W. A SURFACE TROUGH IS TO THE E EXTENDING FROM 32N14W ACROSS THE CANARY ISLANDS ALONG 26N20W TO 22N31W. SCATTERED SHOWERS/ ISOLATED THUNDERSTORMS ARE E OF THE FRONT N OF 27N TO INLAND OVER AFRICA. A SURFACE RIDGE IS OVER CENTRAL ATLC BETWEEN THE FRONTS. UPPER WESTERLY ZONAL FLOW COVERS THE TROPICS AND A WEAK JETSTREAM WITH ESTIMATED WINDS OF 70 TO 95 KT EXTENDS ACROSS THE TROPICS ALONG 16N52W 15N30W ACROSS THE CAPE VERDE ISLANDS TO OVER AFRICA NEAR 19N16W. THE REMAINDER OF THE ATLC UNDER RATHER TRANQUIL CONDITIONS AGAIN THIS MORNING. $$ WALLACE