000 AXNT20 KNHC 300602 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 AM EDT THU OCT 30 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0545 UTC. ...TROPICAL WAVES... A TROPICAL WAVE IS MOVING ACROSS THE CENTRAL CARIBBEAN WITH AXIS EXTENDING FROM 17N70W TO 11N71W...MOVING W AT 15 KT. THE WAVE IS BEING SUPPORTED BY A LOW- TO MIDDLE-LEVEL INVERTED TROUGH AND CONTINUES EMBEDDED IN A SHALLOW MODERATE MOIST ENVIRONMENT. DRY AIR SUBSIDENCE FROM ALOFT IN THIS REGION OF THE BASIN ALONG WITH STRONG DEEP LAYER ENVIRONMENTAL SHEAR INHIBIT THE DEVELOPMENT OF CONVECTION AT THE TIME. ...THE ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA INTO THE E TROPICAL ATLC NEAR 10N14W AND CONTINUES TO 7N23W. THE ITCZ BEGINS NEAR 7N23W AND CONTINUES ALONG 5N34W TO 5N44W. SCATTERED SHOWERS ARE FROM 4N-10N E OF 32W. SCATTERED MODERATE CONVECTION IS FROM 8N- 17N BETWEEN 33W-39W. A SURFACE TROUGH IS WEST OF THE ITCZ ALONG 12N48W TO 4N48W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 7N-11N BETWEEN 47W-53W. ...DISCUSSION... GULF OF MEXICO... A COLD FRONT EXTENDS ACROSS THE SE CONUS INTO THE NORTHERN GULF FROM PENSACOLA FLORIDA TO NEW ORLEANS TO HOUSTON TEXAS...WHICH IS BEING SUPPORTED BY A BROAD MIDDLE- TO UPPER-LEVEL TROUGH OVER THE EASTERN CONUS. ISOLATED SHOWERS ARE WITHIN 60 NM S OF THE FRONT. WEAK SURFACE RIDGING IS AHEAD OF THE COLD FRONT ACROSS THE BASIN...WHICH IS PROVIDING WITH N-NE WIND FLOW IN THE RANGE OF 5-10 KT. A SURFACE PRE-FRONTAL TROUGH IS OVER THE E GULF ALONG 29N86W TO 24N86W WITH NO SHOWERS ASSOCIATED WITH IT DUE TO STRONG DEEP LAYER ENVIRONMENTAL SHEAR AND DRY AIR ACROSS THE REGION. ANOTHER WEAKNESS IN THE RIDGE IS BEING ANALYZED AS A SURFACE TROUGH OVER THE BAY OF CAMPECHE ALONG 24N92W TO 17N95W. SHALLOW MOISTURE ADVECTED TO THE SW GULF FROM THE REMNANTS OF TROPICAL CYCLONE HANNA SUPPORTS SCATTERED SHOWERS WITHIN 200 NM EITHER SIDE OF THE TROUGH AXIS. THE COLD FRONT WILL MOVE ACROSS THE NORTHERN AND CENTRAL FLORIDA PENINSULA THROUGH THU NIGHT AND OVER SOUTH FLORIDA THROUGH FRIDAY NIGHT. A STRONG SURFACE RIDGE BUILDS BEHIND THE FRONT THROUGH THE REMAINDER WEEKEND. CARIBBEAN SEA... DEEP LAYER MOISTURE ASSOCIATED WITH FORMER TROPICAL CYCLONE HANNA LINGERS IN THE NW CARIBBEAN AND NORTHERN CENTRAL AMERICA...WHICH ALONG A DIVERGENT ENVIRONMENT ALOFT CONTINUE TO FUEL SCATTERED MODERATE CONVECTION AND ISOLATED TSTMS S OF 20N W OF 81W. IN THE SW BASIN...ISOLATED MODERATE CONVECTION IS S OF 11N BEING ENHANCED BY THE MONSOON TROUGH THAT CROSSES PANAMA TO NW COLOMBIA. A TROPICAL WAVE IS MOVING OVER THE CENTRAL BASIN BEING SUPPORTED BY AN INVERTED LOW- TO MIDDLE-LEVEL TROUGH...HOWEVER STRONG DRY AIR SUBSIDENCE FROM ALOFT IN THIS REGION OF THE BASIN ALONG WITH STRONG WIND SHEAR HINDER THE DEVELOPMENT OF DEEP CONVECTION. SEE TROPICAL WAVES SECTION ABOVE FOR MORE DETAILS. AN AREA OF LOW PRESSURE CENTERED NE OF THE VIRGIN ISLANDS IS ADVECTING MOISTURE TO PUERTO RICO AND HISPANIOLA THAT IS ENHANCING ISOLATED SHOWERS AT THE TIME. MODEL GUIDANCE INDICATE THE WAVE WILL CONTINUE TO MOVE TOWARDS WESTERN CARIBBEAN WATERS THROUGH THE WEEKEND. THE AREA OF LOW PRESSURE WILL DRIFT W-NW THROUGH FRIDAY NIGHT WHEN IT IS FORECAST TO TRANSITION TO A SURFACE TROUGH BRUSHING NORTHERN HISPANIOLA. HISPANIOLA... SHALLOW MOISTURE ASSOCIATED WITH AN AREA OF LOW PRESSURE NE OF THE VIRGIN ISLANDS IS BEING ADVECTED ACROSS THE ISLAND BY NE WIND FLOW. THIS IS ENHANCING ISOLATED SHOWERS ACROSS THE ISLAND AND ADJACENT WATERS. SHOWER ACTIVITY IS EXPECTED TO INCREASE THROUGH FRIDAY NIGHT WHEN THE AREA OF LOW PRESSURE WEAKEN INTO A TROUGH JUST N OF THE ISLAND. ATLANTIC OCEAN... A SHORT-WAVE UPPER-LEVEL TROUGH OVER THE SW N ATLC SUPPORT A SURFACE TROUGH ALONG 25N70W TO 21N72W THAT IS ENHANCING ISOLATED SHOWERS AND TSTMS FROM 25N-27N BETWEEN 68W-72W. NE OF THE VIRGIN ISLANDS...AN AREA OF LOW PRESSURE ANALYZED AS A 1009 MB LOW NEAR 19N63W CONTINUE TO SUPPORT A CLUSTER OF MODERATE TO ISOLATED STRONG CONVECTION FROM 18N-21N BETWEEN 59W-63W. A MIDDLE TO UPPER LEVEL TROUGH OVER THE CENTRAL ATLC CONTINUE TO SUPPORT A COLD FRONT ANALYZED FROM 30N37W SW TO 26N51W WHERE IT TRANSITIONS TO A STATIONARY FRONT TO 26N63W. SCATTERED SHOWERS ARE NEAR THE TAIL OF THE FRONT FROM 22N-28N BETWEEN 55W-64W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ NR