000 AXNT20 KNHC 261738 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT SUN OCT 26 2014 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1745 UTC. ...TROPICAL WAVES... TROPICAL WAVE IN THE CENTRAL TROPICAL ATLC EXTENDS FROM 17N49W TO 8N50W MOVING W AT 15-20 KT OVER THE PAST 24 HOURS. SSMI TPW AND WATER VAPOR IMAGERY INDICATE THIS WAVE IS EMBEDDED IN AN AREA OF DEEP LAYER MOISTURE. SCATTERED MODERATE CONVECTION IS FROM 8N TO 16N BETWEEN 46W AND 55W. TROPICAL WAVE APPROACHING THE LESSER ANTILLES EXTENDS FROM 16N59W TO 9N60W MOVING W AT 15-20 KT OVER THE PAST 24 HOURS. SSMI TPW AND WATER VAPOR IMAGERY INDICATE THIS WAVE IS EMBEDDED IN AN AREA OF DEEP LAYER MOISTURE. UP TO 35 KT OF WIND SHEAR IS AFFECTING THE WAVE WITH A SMALL UPPER LOW CENTERED JUST WEST OF THE WAVE NEAR 14N61W. THE INTERACTION OF THE WAVE WITH THE UPPER LOW IS HELPING TO ENHANCE CONVECTION IN THE AREA. NUMEROUS MODERATE AND ISOLATED STRONG CONVECTION ARE FROM 9N TO 16N BETWEEN 55W AND 62W. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 13N17W AND CONTINUES TO 11N20W WHERE THE ITCZ BEGINS AND CONTINUES ALONG 8N30W TO 7N43W TO 8N53W. OTHER THAN CONVECTION ASSOCIATED WITH THE TROPICAL WAVES...ISOLATED MODERATE CONVECTION IS FROM 5N TO 9N BETWEEN 26W AND 48W ALONG THE ITCZ. SCATTERED MODERATE CONVECTION IS FROM 8N TO 12N BETWEEN 15W TO 19W...TO THE SOUTH OF THE MONSOON TROUGH. ...DISCUSSION... GULF OF MEXICO... A LARGE UPPER RIDGE EXTENDS FROM CENTRAL AMERICA...NORTHWARD ACROSS THE GULF OF MEXICO...AND ACROSS THE CENTRAL CONUS. A 1019 MB SURFACE HIGH PRESSURE AREA CENTERED NEAR 28N92W COVERS THE GULF WITH ANTICYCLONIC FLOW ACROSS THE BASIN. DRY AIR AND SUBSIDENCE ASSOCIATED WITH THE UPPER RIDGE AND SURFACE HIGH IS SUPPORTING FAIR WEATHER ACROSS THE BASIN. OVER THE NEXT 24 HOURS THE SURFACE HIGH WILL SHIFT INTO THE W ATLANTIC WHILE THE UPPER RIDGE BEGINS TO FLATTEN OUT ACROSS THE REGION. DRY AIR WILL MAINTAIN FAIR WEATHER OVER THE BASIN THROUGH MONDAY. CARIBBEAN SEA... AN UPPER TROUGH IN THE W ATLANTIC EXTENDS S ACROSS CUBA INTO THE W CARIBBEAN. THIS TROUGH SUPPORTS A COLD FRONT FROM 20N76W TO 19N80 WITH A DECAYING COLD FRONT FROM 18N80W TO A 1007 MB LOW CENTERED NEAR 16N82W. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE WITHIN 100 NM OF THE COLD FRONT. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION ARE FROM 14N TO 18N BETWEEN 79W AND 83W. ISOLATED THUNDERSTORMS ARE OVER THE SW CARIBBEAN N OF PANAMA TO 12N...W OF 81W. THIS ACTIVITY IS PRIMARILY ASSOCIATED WITH THE EAST EXTENSION OF THE PACIFIC MONSOON TROUGH. FARTHER EAST...A SURFACE TROUGH...FORMERLY A TROPICAL WAVE...EXTENDS FROM 18N76W TO 12N76W. RELATIVELY DRY AIR IN THE VICINITY OF THIS TROUGH IS LIMITING CONVECTION WITH THIS TROUGH AND ELSEWHERE ACROSS THE CENTRAL CARIBBEAN. SCATTERED THUNDERSTORMS ARE BEGINNING TO AFFECT THE WINWARD ISLANDS AS A TROPICAL WAVE APPROACHES FROM THE CENTRAL ATLANTIC. SEE THE TROPICAL WAVES SECTION ABOVE. OVER THE NEXT 24 HOURS THE TROPICAL WAVE WILL CROSS THE LESSER ANTILLES WITH CONVECTION. THE LOW IN THE W CARIBBEAN WILL DRIFT W WITH CONVECTION. THE COLD FRONT WILL GRADUALLY DISSIPATE OVER THE NEXT 48 HOURS AS IT MOVES SLOWLY SE. SHOWERS AND ISOLATED THUNDERSTORMS ARE EXPECTED TO CONTINUE ALONG THE FRONT. HISPANIOLA... THE COLD FRONT TO THE NE OF HISPANIOLA IS PRODUCING SOME SHOWERS ACROSS HAITI WITH ISOLATED THUNDERSTORMS JUST OFFSHORE THE NE COAST OF HAITI. OVER THE NEXT 48 HOURS THE COLD FRONT WILL DISSIPATE AS IT APPROACHES HAITI. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WILL BE POSSIBLE ACROSS HISPANIOLA THROUGH TUESDAY. A TROPICAL WAVE WILL PASS SOUTH OF THE ISLAND TUESDAY NIGHT. ATLANTIC OCEAN... AN UPPER TROUGH OVER THE W ATLANTIC IS SUPPORTING A COLD FRONT FROM 31N63W ACROSS THE S BAHAMAS TO THE COAST OF CUBA NEAR 20N75W. SCATTERED MODERATE CONVECTION IS WITHIN 100 NM SE OF THE FRONT. SCATTERED SHOWERS ARE WITHIN 100 NM NW OF THE FRONT. N TO NE WINDS UP TO 20 KT ARE TO THE NE THE FRONT WITH SW WINDS UP TO 20 KT SE OF THE FRONT TO 60W. EAST OF 60W...A 1020 MB SURFACE HIGH CENTERED NEAR 30N40W DOMINATES THE CENTRAL ATLANTIC WITH ANTICYCLONIC FLOW AND FAIR WEATHER. A WEAK 1015 MB SURFACE LOW NEAR 28N27W IS PRODUCING SOME SHOWER ACTIVITY WITHIN 100 NM OF THE LOW CENTER. OVER THE NEXT 24 HOURS THE COLD FRONT WILL SLIDE EAST TO NEAR 30N60W TO JUST OFFSHORE OF HAITI WITH CONVECTION. THE FRONT WILL THEN DISSIPATE BY TUESDAY WITH HIGH PRESSURE BECOMING CENTERED OVER THE W ATLANTIC. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ LATTO