000 AXNT20 KNHC 120522 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT TUE OCT 12 2011 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...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0445 UTC. ...TROPICAL WAVES... TROPICAL WAVE WAS INTRODUCED AT 12/0000 UTC OFF THE COAST OF W AFRICA ALONG 17W/18W S OF 15N DRIFTING W. WAVE WAS WELL DEFINED WHILE INLAND OVER AFRICA BUT IS NOT AS EVIDENT NOW THAT IT IS OVER WATER. UNORGANIZED CLUSTERS OF SCATTERED MODERATE TO SCATTERED STRONG CONVECTION DOT THE AREA FROM 4N-12N BETWEEN 12W-23W. TROPICAL WAVE IS IN THE E CARIBBEAN ALONG 64W/65W S OF 18N MOVING W NEAR 10 KT. WAVE CONTINUES TO WEAKEN AND IS LESS DISTINCT ON SATELLITE IMAGERY. NO ASSOCIATED CONVECTION IS NOTED. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA BUT DOES NOT ENTER THE E TROPICAL ATLC. THE ITCZ EXTENDS FROM 7N25W ALONG 8N33W TO SOUTH AMERICA NEAR 6N54W. CLUSTERS OF SCATTERED MODERATE/ ISOLATED STRONG CONVECTION ARE FROM 5N-8N BETWEEN 23W-28W... FROM THE ITCZ AXIS TO 12N BETWEEN 28W-42W...AND FROM THE ITCZ AXIS TO 10N BETWEEN 44W-50W. ...DISCUSSION... GULF OF MEXICO... BROAD UPPER RIDGE DOMINATES THE GULF WATERS ANCHORED OVER S MEXICO NEAR CIUDAD DEL CARMEN. HOWEVER...A SHORTWAVE UPPER TROUGH IS MOVING NE THROUGH GEORGIA SUPPORTING A 1008 MB SURFACE LOW AT 12/0300 UTC IS CENTERED NEAR TALLAHASSEE FLORIDA AND A SURFACE TROUGH EXTENDING INTO THE GULF ALONG 26N86W 23N91W TO A 1009 MB LOW IN THE SW GULF NEAR 23N92W. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE WITHIN 60 NM EITHER SIDE OF THE SURFACE TROUGH AND SURROUNDING THE SW GULF LOW. BROKEN/ OVERCAST LOW CLOUDS WITH PATCHES OF FOG AND DRIZZLE COVER THE NE GULF N OF 27N BETWEEN 83W-90W. SOME UPPER LEVEL MOISTURE IS BEING DRAWN ACROSS MEXICO TO OVER THE NW GULF FROM HURRICANE JOVA IN THE E PACIFIC REGION. OTHERWISE...THE REMAINDER OF THE GULF IS EXPERIENCING FAIR CONDITIONS TONIGHT. THE 1008 MB LOW OVER THE FLORIDA PANHANDLE WILL MOVE NE WITH THE TRAILING TROUGH SHIFTING E OF THE GULF WED NIGHT INTO THU AS A WEAK COLD FRONT MOVES INTO THE NW GULF. THIS FRONT WILL QUICKLY REACH FROM NEAR TAMPA FLORIDA TO THE FAR SW GULF AND BECOME STATIONARY FROM NW CUBA TO THE NORTHERN YUCATAN PENINSULA THEN BEGIN TO DRIFT NW SAT AND SUN. HIGH PRESSURE WILL BUILD E ACROSS THE GULF BEHIND THE FRONT. BROAD LOW PRESSURE IN THE E PACIFIC WILL SHIFT INLAND ACROSS CENTRAL AMERICA THU WITH BROAD CYCLONIC CIRCULATION EXPECTED TO ENCOMPASS CENTRAL AMERICA...THE W CARIBBEAN AND S GULF OF MEXICO SAT AND SUN. CARIBBEAN SEA... THE UPPER RIDGE THAT DOMINATES THE GULF OF MEXICO COVERS THE W CARIBBEAN W OF 80W ENHANCING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS INLAND OVER HONDURAS/GUATEMALA AND WITHIN 60 NM ALONG THE COAST W OF 84W. A SHARP NARROW UPPER TROUGH OVER THE FAR W ATLC EXTENDS ACROSS CUBA INTO THE CENTRAL CARIBBEAN N OF 13N BETWEEN 72W-80W SUPPORTING A LOW BETWEEN THE N COAST OF CUBA AND THE BAHAMAS AND A SURFACE TROUGH THAT EXTENDS FROM THE LOW ACROSS CUBA NEAR SANTIAGO DE CUBA TO MONTEGO BAY JAMAICA. DRY AIR ALOFT IS BEING FUNNELED INTO THE W CARIBBEAN BY THE UPPER RIDGE THEN INTO THE UPPER TROUGH AT THE BASE GIVING THE REMAINDER OF THE W CARIBBEAN FAIR WEATHER TONIGHT. THE MONSOON TROUGH HAS LIFTED N AND NOW EXTENDS FROM 13N76W ALONG 12N81W ACROSS CENTRAL AMERICA AND INTO THE E PACIFIC REGION ACROSS NICARAGUA NEAR 13N84W WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF THE TROUGH AXIS W OF 81W. A SHARP NARROW UPPER RIDGE EXTENDS FROM COLOMBIA NEAR 12N72W ACROSS THE DOMINICAN REPUBLIC NEAR 18N70W INDUCED BY A LARGE UPPER TROUGH OVER THE CENTRAL ATLC THAT EXTENDS S OVER THE FAR E CARIBBEAN AND THE W TROPICAL ATLC. THE UPPER RIDGE IS ENHANCING SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS THAT DOT THE AREA WITHIN 150/175 NM OF LINE FROM PANAMA/COLOMBIA NEAR 9N77W TO HISPANIOLA NEAR 18N72W LEAVING THE E CARIBBEAN UNDER FAIR CONDITIONS TONIGHT. BROAD LOW PRESSURE IN THE E PACIFIC WILL SHIFT INLAND ACROSS CENTRAL AMERICA THU WITH BROAD CYCLONIC CIRCULATION EXPECTED TO ENCOMPASS CENTRAL AMERICA...THE W CARIBBEAN AND S GULF OF MEXICO SAT AND SUN. ATLANTIC OCEAN... A SHARP NARROW UPPER TROUGH EXTENDS ALONG 79W OVER THE BAHAMAS AND INTO THE CENTRAL CARIBBEAN SUPPORTING A 1010 MB LOW CENTERED BETWEEN THE BAHAMAS AND THE N COAST OF CUBA NEAR 22N75W WITH A SURFACE TROUGH EXTENDING INTO THE CARIBBEAN ACROSS E CUBA NEAR SANTIAGO DE CUBA GENERATING SCATTERED SHOWERS/THUNDERSTORMS FROM 20N-24N BETWEEN 70W-75W WITH SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS N OF 24N BETWEEN 70W-76W. A NARROW UPPER RIDGE IS TO THE E ALONG 69W INDUCED BY A LARGE UPPER TROUGH THAT COVERS THE CENTRAL ATLC EXTENDING THROUGH 32N45W ALONG 23N53W ACROSS THE W TROPICAL ATLC/E CARIBBEAN TO SOUTH AMERICA OVER CENTRAL SURINAME. A WEAK SURFACE TROUGH IS ALONG THE E SIDE OF THE UPPER TROUGH EXTENDING FROM 28N37W TO 21N45W. SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS ARE WITHIN 90 NM EITHER SIDE OF THE SURFACE TROUGH. WEAK HIGH PRESSURE COVERS THE ATLC BETWEEN 22N-32N WITH A 1019 MB HIGH NEAR BERMUDA. THE 1010 MB LOW IN THE W ATLC WILL LIFT N THROUGH THE CENTRAL BAHAMAS TONIGHT THROUGH WED THEN DISSIPATE. A WEAK COLD FRONT WILL ENTER NW PORTION OF THE AREA WED NIGHT REACHING FROM E OF BERMUDA TO STRAITS OF FLORIDA BY SAT MORNING WHERE IT WILL STALL THEN BEGIN TO DRIFT NW SAT NIGHT. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW