000 AXNT20 KNHC 181139 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT TUE OCT 18 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1130 UTC. ...TROPICAL WAVES... TROPICAL WAVE IS ANALYZED FROM 16N26W TO 10N31W MOVING W AT 15-20 KT. WAVE WAS RELOCATED BASED ON THE UPPER LEVEL WINDS... SURFACE OBSERVATIONS...AND SATELLITE IMAGERY. WAVE IS WELL DEFINED AND IS EMBEDDED WITHIN A MOISTURE SURGE AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. WAVE REMAINS BENEATH AN UPPER RIDGE ENHANCING SCATTERED MODERATE/STRONG CONVECTION FROM 13N-17N BETWEEN 20W-30W INCLUDING THE CAPE VERDE ISLANDS. TROPICAL WAVE IS ANALYZED IN THE CENTRAL TROPICAL ATLC FROM 13N43W TO 7N45W MOVING W NEAR 10 KT. WAVE WAS RELOCATED BASED ON THE UPPER LEVEL WINDS...SURFACE OBSERVATIONS...AND SATELLITE IMAGERY. WAVE WELL DEFINED AND IS AT THE LEADING EDGE OF A MOISTURE SURGE AS DEPICTED ON THE TOTAL PRECIPITABLE WATER IMAGERY. CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION ARE FROM 7N-10N BETWEEN 42W-47W. TROPICAL WAVE IS ANALYZED IN THE E CARIBBEAN ALONG 67W/68W S OF 17N MOVING 10-15 KT. WAVE IS WELL DEFINED IN THE UPPER LEVEL SATELLITE WINDS AND IN THE LOW LEVEL CLOUD PATTERN ON SATELLITE IMAGERY S OF 16N. ISOLATED SHOWERS ARE S OF 15N TO THE COAST OF VENEZUELA BETWEEN 65W-70W. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA TO THE COAST NEAR 15N17W. THE ITCZ IS DISRUPTED BY THE PRESENCE OF THE TROPICAL WAVES. SCATTERED MODERATE/STRONG CONVECTION IS FROM 5N-10N BETWEEN 14W-19W. CLUSTERS OF SCATTERED MODERATE/ISOLATED STRONG CONVECTION ARE WITHIN 45 NM OF 6N BETWEEN 33W-39W. ...DISCUSSION... GULF OF MEXICO... A BROAD AREA OF LOW PRESSURE COVERS MOST OF THE GULF INTO THE NW CARIBBEAN WITH A 1002 MB LOW CENTERED OFF THE N COAST OF THE YUCATAN PENINSULA NEAR 23N89W AND A SECOND 1003 MB SURFACE LOW DEVELOPING TO THE N AT 18/0900 UTC NEAR 26N88W WITH A SURFACE TROUGH FORMING BETWEEN THE LOWS. SCATTERED/NUMEROUS STRONG CONVECTION IS FROM 24N-27N BETWEEN 82W-86W WITH SCATTERED TO HEAVY RAINS COVERING THE REMAINDER OF THE AREA S OF 27N E OF 86W TO INLAND OVER FLORIDA/CUBA AND THROUGH THE STRAITS OF FLORIDA. A BROAD UPPER RIDGE COVERS THE GULF ANCHORED JUST N OF THE YUCATAN CHANNEL. THERE REMAINS A DISTINCT BOUNDARY BETWEEN THE MOIST TROPICAL AIR TO THE SE AND STRONG SUBSIDENCE/DRY STABLE AIR TO THE NW THAT EXTENDS FROM CEDAR KEY FLORIDA ALONG 28N86W 23N90W TO TAMPICO MEXICO. THE 1003 MB LOW WILL MOVE N-NE THROUGH WED WITH THE NEW LOW MOVING INLAND NEAR THE FLORIDA BIG BEND REGION WED NIGHT. THE NEW LOW WILL DEVELOP A FRONTAL BOUNDARY ACROSS THE E GULF TONIGHT THROUGH WED NIGHT IN ADVANCE OF A STRONG COLD FRONT CURRENTLY OVER E TEXAS THAT WILL PUSH INTO THE NW GULF THIS MORNING. THIS STRONGER FRONT WILL MOVE QUICKLY SE ACROSS THE AREA TO SE OF THE GULF WED EVENING. HIGH PRESSURE WILL BUILD OVER THE ENTIRE AREA GULF IN THE WAKE OF THE FRONTS THROUGH SAT. CARIBBEAN SEA... THE UPPER RIDGE ANCHORED JUST N OF THE YUCATAN CHANNEL COVERS MOST OF THE CARIBBEAN WITH AN E/W UPPER RIDGE OVER THE TROPICAL ATLC COVERING THE SE CARIBBEAN SE OF A LINE FROM NEAR ANTIGUA AND BARBUDA IN THE LEEWARD ISLANDS TO THE GUAJIRA PENINSULA OF COLOMBIA. THE BROAD AREA OF LOW PRESSURE OVER THE SE GULF OF MEXICO COVERS THE NW CARIBBEAN AND COUPLED WITH THE UPPER RIDGE OVER THE NW CARIBBEAN IS GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS WITHIN 60/75 NM OF LINE FROM THE YUCATAN CHANNEL NEAR 22N85W TO OFF THE COAST OF BELIZE NEAR 17N88W. EASTERLY SURFACE FLOW COMBINED WITH THE EASTERLY FLOW ALOFT OVER THE SW CARIBBEAN IS GENERATING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS S OF 12N W OF 74W TO OVER COLOMBIA AND CENTRAL AMERICA. BROAD LOWER PRESSURE OVER THE SE GULF AND NW CARIBBEAN WILL LIFT N-NE TODAY THROUGH WED NIGHT AS A WEAK PRESSURE PATTERN CONTINUES OVER MUCH OF THE CARIBBEAN. A WEAK COLD FRONT WILL MOVE INTO THE NW CARIBBEAN TONIGHT INTO EARLY WED THEN BE ABSORBED BY A STRONGER COLD FRONT THAT PUSHES INTO THE NW CARIBBEAN WED EVENING. THIS COLD FRONT WILL REACH FROM CENTRAL CUBA TO NE HONDURAS BY LATE THU WHERE IT WILL STALL AND BEGIN TO WEAKEN THROUGH SAT. THE TROPICAL WAVE WILL WEAKEN OVER THE CENTRAL CARIBBEAN LATE WED NIGHT. ATLANTIC OCEAN... AN UPPER RIDGE AXIS EXTENDS FROM THE YUCATAN CHANNEL THROUGH THE STRAITS OF FLORIDA NEAR 24N80W ALONG 26N62W TO 30N50W PROVIDING A DIFFLUENT ENVIRONMENT TO ENHANCE SCATTERED SHOWERS AND POSSIBLE ISOLATED THUNDERSTORMS WITHIN 150 NM OF LINE FROM OVER FLORIDA NEAR 27N80W ALONG 29N70W TO 32N53W. AN UPPER TROUGH EXTENDS ACROSS THE CENTRAL ATLC FROM AN UPPER LOW NEAR 30N29W THROUGH A SECOND UPPER LOW NEAR 20N51W INTO THE W TROPICAL ATLC TO NEAR 16N57W. THE NORTHERN UPPER LOW IS SUPPORTING A WEAK 1014 MB LOW CENTERED NEAR 31N36W WITH A SURFACE TROUGH EXTENDING S ALONG 29N35W TO 26N38W WITH SCATTERED SHOWERS/ISOLATED THUNDERSTORMS FROM 29N-33N BETWEEN 23W-33W. A WEAK SURFACE RIDGE COVERS MOST OF THE ATLC N OF 20N E OF 80W WITH A WEAKNESS IN THE VICINITY OF THE ABOVE LOW/TROUGH. A BROAD UPPER RIDGE EXTENDS E/W ACROSS THE TROPICAL ATLC. SURFACE RIDGE OVER THE W ATLC WILL SHIFT E AND WEAKEN THROUGH EARLY WED. THE BROAD LOW PRESSURE OVER THE GULF OF MEXICO/NW CARIBBEAN WILL TRACK N-NE THROUGH WED AHEAD OF A STRONG COLD FRONT THAT WILL MOVE OFF THE NE FLORIDA COAST WED EVENING. THE FRONT WILL REACH FROM 31N74W TO CENTRAL CUBA BY EARLY THU THEN WEAKEN AND BECOME STATIONARY FROM NEAR 31N70W TO CENTRAL CUBA FRI AND SAT. WEAK HIGH PRESSURE WILL BUILD ACROSS THE AREA BEHIND THE FRONT. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ PAW