Issued by NWS
000 AXNT20 KNHC 232347 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 705 PM EST MON NOV 23 2009 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 2315 UTC. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 5N10W 5N20W 8N34W 5N40W 6N60W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 4N-9N BETWEEN 23W-30W. AN EMBEDDED SURFACE TROUGH IS ALONG 10N34W 3N34W. ISOLATE MODERATE CONVECTION IS FROM 5N-9N BETWEEN 30W-40W. SCATTERED SHOWERS ARE ALSO FROM 3N-7N BETWEEN 40W-55W. ...DISCUSSION... GULF OF MEXICO... AS OF 2100 UTC...A SURFACE TROUGH EXTENDS FROM SOUTH FLORIDA TO THE CENTRAL GULF OF MEXICO TO SOUTH TEXAS ALONG 27N80W 25N90W 26N97W. WIDELY SCATTERED MODERATE CONVECTION IS OVER THE WESTERN GULF ALONG THE FRONT FROM 24N-27N BETWEEN 90W-97W. SCATTERED SHOWERS ARE ALSO OVER THE EASTERN FRONT WITHIN 120 NM OF THE FRONT E OF 90W. SURFACE WINDS ARE MAINLY 10-15 KT THROUGHOUT THE GULF. IN THE UPPER LEVELS...THE EASTERN HALF OF AN UPPER LEVEL TROUGH IS OVER THE GULF PRODUCING SW UPPER LEVEL FLOW. STRONG SUBSIDENCE IS OVER TEXAS AND THE NW GULF. THE REMAINDER OF THE GULF HAS SIGNIFICANT UPPER LEVEL MOISTURE. A 70-90 KT UPPER LEVEL JETSTREAM IS NOTED EXTENDING FROM TAMPICO MEXICO TO TAMPA FLORIDA. EXPECT...THE SURFACE TROUGH TO PERSIST FOR THE NEXT 24 HOURS WITH CONVECTION AND SHOWERS. ALSO EXPECT MORE SURFACE MOISTURE TO ADVECT OVER THE YUCATAN PENINSULA AND THE SE GULF FROM THE NW CARIBBEAN OVER THE NEXT 24 HOURS. CARIBBEAN SEA... THE SURFACE PRESSURE GRADIENT OVER THE CARIBBEAN HAS TIGHTENED THUS FRESH TO STRONG TRADEWINDS DOMINATES THE BASIN WITH STRONGEST WINDS ALONG THE COAST OF N COLOMBIA. A 1007 MB LOW IS CENTERED OVER PANAMA NEAR 8N79W. WIDELY SCATTERED MODERATE CONVECTION IS OVER THE SW CARIBBEAN...PANAMA...AND COSTA RICA FROM 7N-12N BETWEEN 80W-84W. SCATTERED MODERATE CONVECTION IS ALSO OVER E CUBA FROM 20N-22N BETWEEN 75W-79W. PATCHES OF BROKEN TO OVERCAST LOW CLOUDS WITH SCATTERED SHOWERS DOTS THE W CARIBBEAN AND CENTRAL AMERICA NAMELY W OF 85W TO INCLUDE THE YUCATAN PENINSULA. IN THE UPPER LEVELS...A BROAD RIDGE WITH RIDGE AXIS ALONG 75W IS OVER THE ENTIRE CARIBBEAN. DRY AIR AND SUBSIDENCE COVERS THE AREA EXCEPT OVER THE YUCATAN CHANNEL...AND THE SW CARIBBEAN...WHERE WITH UPPER LEVEL MOISTURE PREVAILS. EXPECT...SHOWERS/THUNDERSTORMS TO CONTINUE OVER THE W CARIBBEAN W OF 80W OVER THE NEXT 24 HOURS. ATLANTIC OCEAN... A 1015 MB LOW IS LOCATED OVER THE COAST OF NORTH CAROLINA NEAR 34N77W. A SURFACE TROUGH EXTENDS S TO SOUTH FLORIDA ALONG 30N77W 27N80W. SCATTERED SHOWERS ARE WITHIN 60 NM OF THE TROUGH. A 1019 MB HIGH IS FURTHER E NEAR 27N72W. A SURFACE TROUGH IS OVER THE CENTRAL ATLANTIC FROM 32N47W TO 26N50W. WIDELY SCATTERED CONVECTION IS E OF THE TROUGH AXIS FROM 26N-31N BETWEEN 44W-48W. ANOTHER SURFACE TROUGH IS FURTHER S APPROACHING THE LESSER ANTILLES ALONG 20N55W 11N58W. SCATTERED SHOWERS ARE FROM 9N-14N BETWEEN 57W-62W. A 1031 MB HIGH IS CENTERED OVER THE E ATLANTIC NEAR 37N16W. A RIDGE AXIS EXTENDS SW FROM THE HIGH TO 25N38W. EXPECT OVER THE NEXT 24 HOURS...MORE CONVECTION OVER THE N FLORIDA COAST...OVER THE BAHAMAS...AND OVER THE CENTRAL ATLANTIC N OF 25N BETWEEN 45W-55W. $$ FORMOSA
