000 AXNT20 KNHC 211701 TWDAT TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT THU OCT 21 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1645 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ALONG 30W/31W FROM 4N-17N AND MOVING WESTWARD AT 8 KNOTS OVER THE PAST 24 HOURS. CYCLONIC CURVATURE OF THE CLOUD FIELD IS NOTED ON SATELLITE IMAGERY. SCATTERED SHOWERS ARE NOTED FROM 14N-18N BETWEEN 25W-34W. ...ITCZ... THE ITCZ AXIS IS CENTERED ALONG 10N15W 8N20W 9N30W 6N35W 11N44W 11N61W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 3N-8N BETWEEN 18W-23W. ISOLATED MODERATE CONVECTION IS FROM 1N-6N BETWEEN 30W-37W. ...DISCUSSION... GULF OF MEXICO... A 1028 MB HIGH CENTERED OVER WESTERN NORTH CAROLINA NEAR 36N83W IS PRODUCING SURFACE RIDGING OVER THE ENTIRE GULF OF MEXICO. THE SURFACE PRESSURE GRADIENT HAS INCREASED OVER THE GULF...THUS WINDS ARE NOW 15-20KT FROM THE NE OVER THE E GULF E OF 90W...AND 15-20KT FROM THE SE OVER THE W GULF. PATCHES OF BROKEN TO OVERCAST LOW CLOUDS ARE OVER THE GULF. IN THE UPPER LEVELS... AN UPPER LEVEL TROUGH IS OVER THE FAR E GULF AND FLORIDA. AN UPPER LEVEL HIGH IS CENTERED OVER S MEXICO NEAR 18N98W. UPPER LEVEL RIDGING IS OVER THE W GULF W OF 85W PRODUCING NW FLOW. STRONG SUBSIDENCE IS OVER THE E GULF E OF 87W WHILE CONSIDERABLE MOISTURE IS OVER THE W GULF. WITHIN 24 HOURS...A COLD FRONT WILL BE APPROACHING THE TEXAS COAST. EXPECT PREFRONTAL CONVECTION OVER THE NW GULF OVER THE NEXT 24 HOURS. CARIBBEAN SEA... RESIDUAL CONVECTION ASSOCIATED WITH A DISSIPATED STATIONARY FRONT IS SOUTH OF CUBA FROM 17N-20N BETWEEN 75W-85W. A QUASI-STATIONARY 1008 MB LOW IS CENTERED OVER THE SW CARIBBEAN NEAR 11N82W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 8N-14N BETWEEN 76W-84W. A 1010 MB LOW IS LOCATED IN THE GULF OF HONDURAS NEAR 17N88W. SCATTERED SHOWERS ARE WITHIN 60 NM OF THE CENTER. THE E CARIBBEAN E OF 70W HAS MOSTLY FAIR WEATHER... HOWEVER ISOLATED SHOWERS ARE NOTED. MODERATE TO FRESH TRADEWINDS ARE OVER THE CARIBBEAN. IN THE UPPER LEVELS...UPPER LEVEL TROUGHING IS OVER THE WESTERN AND EASTERN CARIBBEAN...WITH RIDGING PREVAILING IN THE CENTRAL CARIBBEAN. SIGNIFICANT UPPER LEVEL MOISTURE IS OVER THE W CARIBBEAN W OF 70W. STRONG SUBSIDENCE IS OVER THE E CARIBBEAN. EXPECT THE LOW IN THE GULF OF HONDURAS TO DISSIPATE WHILE THE LOW IN THE SW CARIBBEAN TO REMAIN STATIONARY OVER THE NEXT 24 HOURS. ATLANTIC OCEAN... THE TAIL END OF A COLD FRONT IS OVER THE W ATLANTIC FROM 32N53W TO 28N59W. A DISSIPATING STATIONARY FRONT CONTINUES TO E CUBA ALONG 24N67W 20N74W. WIDELY SCATTERED MODERATE CONVECTION IS OVER THE S BAHAMAS FROM 21N-25N BETWEEN 70W-75W. SCATTERED SHOWERS ARE OVER THE REMAINDER OF THE FRONT. A SURFACE TROUGH IS FROM 28N51W TO 19N55W. AN EMBEDDED 1010 MB LOW IS ON THE TROUGH AXIS NEAR 25N52W. A 1019 MB HIGH IS OVER THE CENTRAL ATLANTIC NEAR 28N29W. IN THE TROPICS...A 1009 MB LOW IS JUST NORTH OF THE ITCZ NEAR 13N40W. SCATTERED SHOWERS ARE WITHIN 90 NM OF THE CENTER. IN THE UPPER LEVELS...AN UPPER LEVEL TROUGH IS OVER THE W ATLANTIC N OF 20N AND W OF 70W. AN UPPER LEVEL RIDGE IS BETWEEN 55W-70W. AN UPPER LEVEL LOW IS OVER THE CENTRAL ATLANTIC NEAR 24N47W. UPPER LEVEL DIFFLUENCE E OF THE CENTER IS PRODUCING WIDELY SCATTERED MODERATE CONVECTION FROM 23N-31N BETWEEN 38W-48W. AN UPPER LEVEL HIGH IS OVER THE TROPICAL ATLANTIC NEAR 10N40W. AN UPPER LEVEL RIDGE AXIS EXTENDS NE FROM THIS CENTER TO 25N25W. EXPECT...MORE CONVECTION ALONG THE ITCZ ESPECIALLY E OF 35W OVER THE NEXT 24 HOURS. $$ AL/MRF