000 AXNT20 KNHC 062347 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT WED JUL 06 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...TROPICAL WAVES... TROPICAL WAVE IN THE CENTRAL TROPICAL ATLC EXTENDS FROM 11N40W TO 4N43W MOVING W 10-15 KT. WHILE THIS WAVE IS LOW AMPLITUDE AND MAINLY EMBEDDED WITHIN THE ITCZ...A TRACKABLE AND COHERENT FEATURE CAN BE TRACED BACK TO AFRICA. CURRENTLY SCATTERED MODERATE/STRONG CONVECTION IS FROM 4N-10N BETWEEN 40W-50W. TROPICAL WAVE APPROACHING THE LESSER ANTILLES EXTENDS FROM 20N56W TO 13N59W MOVING W 15-20 KT. THE WAVE PRECEDES A LARGE SURGE OF DEEP LAYER MOISTURE EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE/STRONG CONVECTION IS MOVING ACROSS THE WINDWARD ISLANDS FROM 12N-18N BETWEEN 57W-62W. SOME OF THIS ACTIVITY MAY BE ASSOCIATED WITH A SURFACE TROUGH JUST W OF THE WAVE AXIS AS WELL AS DIFFLUENCE ALOFT. TROPICAL WAVE IS ACROSS THE YUCATAN PENINSULA EXTENDING FROM 24N85W TO 18N90W MOVING WNW AT 10-15 KT. THE WAVE LIES IN A BROAD AREA OF CYCLONIC FLOW AS WELL AS IN A LARGE AREA OF DEEP LAYER MOISTURE COVERING MUCH OF THE NW CARIBBEAN AND SE GULF OF MEXICO. THE WAVE ALSO IS UNDER AN AREA OF DIFFLUENCE ALOFT FURTHER SUPPORTING CONVECTION. NUMEROUS STRONG CONVECTION IS OVER THE YUCATAN...GUATEMALA...AND BELIZE FROM 16N-19N BETWEEN 88W-91W. SCATTERED MODERATE/STRONG CONVECTION IS FROM 19N-23N BETWEEN 86W-90W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA FROM THE PRIME MERIDIAN AT 21N ALONG 16N12W 11N20W. THE ITCZ CONTINUES FROM 11N20W ALONG 10N30W 9N39W 4N53W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 6N-8N BETWEEN 34W-36W. ISOLATED MODERATE/STRONG CONVECTION IS FROM 3N-9N BETWEEN 50W-55W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL LOW CONTINUES TO SPIN OVER THE GULF OF MEXICO THIS EVENING NEAR 27N91W WITH TROUGH AXIS EXTENDING FROM CENTRAL ALABAMA TO THE BAY OF CAMPECHE. DRY AIR IS WRAPPING AROUND THE WRN SIDE OF THE UPPER TROUGH MAINTAINING FAIR SURFACE CONDITIONS W OF 87W BESIDES A FEW ISOLATED SHOWERS/THUNDERSTORMS ACROSS LOUISIANA AND ERN TEXAS. THE ERN GULF IS EXPERIENCING MOIST CONDITIONS WITH A LARGE AREA OF DEEP LAYER MOISTURE COVERING THE SE GULF EXTENDING FROM THE WRN ATLC AND NW CARIBBEAN. SOME OF THIS IS ASSOCIATED WITH A TROPICAL WAVE ACROSS THE YUCATAN PENINSULA. SEE TROPICAL WAVE SECTION FOR MORE DETAILS. A SURFACE TROUGH IS E OF THE FLORIDA PENINSULA SUPPORTING SHOWER ACTIVITY AS WELL. THIS AREA ALSO LIES UNDERNEATH THE DIFFLUENT SIDE OF THE UPPER TROUGH WHICH IS HELPING ENHANCE ACTIVITY. THE COMBINATION OF THESE FEATURES IS SUPPORTING A WIDE AREA OF SHOWERS/THUNDERSTORMS ACROSS CUBA...THE STRAITS OF FLORIDA...AND SRN FLORIDA S OF 28N E OF 85W. A FEW SHOWERS/THUNDERSTORMS ARE ALSO OVER NRN FLORIDA. EXPECT MOIST CONDITIONS TO REMAIN OVER THE ERN GULF AS THE TROPICAL WAVE MOVES WNW...AND THE SURFACE TROUGH E OF THE BASIN MOVES W. THE UPPER LOW IS ALSO EXPECTED TO REMAIN RELATIVELY STATIONARY PLACING THE ERN GULF UNDER A DIFFLUENT ZONE. CARIBBEAN SEA... THE NW CARIBBEAN REMAINS UNDER ENHANCED DEEP LAYER MOISTURE STILL REMAINING FROM A TROPICAL WAVE THAT IS NOW OVER THE YUCATAN PENINSULA. CURRENTLY STRONG SHOWERS/THUNDERSTORMS ARE ACROSS MUCH OF CUBA WITH SOME SLIGHTLY LIGHTER ACTIVITY S OF THE ISLAND N OF 18N BETWEEN 79W-85W. ALOFT...AN UPPER LEVEL RIDGE IS CENTERED S OF CUBA NEAR 20N82W WITH AXIS EXTENDING TO THE NE. DRY AIR IS WRAPPING AROUND THE SE SIDE OF THE RIDGE PROVIDING FAIR CONDITIONS ACROSS THE SW AND CENTRAL CARIBBEAN. THIS IS PROVIDING SOME BRIEF RELIEF TO HISPANIOLA WHERE RAINFALL AMOUNTS HAVE BEEN REPORTED UP TO 8 INCHES OVER THE PAST 24 HOURS. AN AREA OF SHOWERS/THUNDERSTORMS IS IN THE FAR SW CARIBBEAN S OF 12N W OF 79W INFLUENCED BY THE MONSOON TROUGH EXTENDING ACROSS COSTA RICA TO NRN COLOMBIA. THE ERN CARIBBEAN IS ALSO UNDER MOIST CONDITIONS AS AN AREA OF DEEP LAYER MOISTURE MOVES INTO THE AREA FROM THE WRN TROPICAL ATLC. SOME OF THIS MOISTURE IS ASSOCIATED WITH A SURFACE TROUGH EXTENDING FROM 15N60W TO 10N64W...AND WITH A TROPICAL WAVE STILL E OF THE ISLANDS. STRONG SHOWERS/THUNDERSTORMS ARE MOVING ACROSS THE WINDWARD ISLANDS FROM 12N-17N E OF 63W WITH MORE ISOLATED ACTIVITY FROM 12N-16N BETWEEN 63W-69W. SOME OF THIS PRECIPITATION IS ENHANCED BY DIFFLUENCE ALOFT AROUND AN UPPER LEVEL TROUGH IN THE CENTRAL ATLC THAT EXTENDS INTO THE NE CARIBBEAN. EXPECT MOIST CONDITIONS TO CONTINUE OVER THE ERN CARIBBEAN AND MOVE INTO THE CENTRAL BASIN AS THE SURFACE TROUGH AND TROPICAL WAVE MOVE WWD. ATLANTIC OCEAN... DESPITE UPPER LEVEL RIDGING COVERING THE FAR W ATLC...A SURFACE TROUGH EXTENDING OFF THE E COAST OF FLORIDA FROM NEAR 28N78W TO 23N71W IS SUPPORTING A LARGE AREA OF SHOWERS/THUNDERSTORMS S OF 28N W OF 74W WITH THE STRONGEST ACTIVITY OVER ERN CUBA. TO THE E...AN UPPER LEVEL TROUGH EXTENDS FROM NEAR 36N46W TO 19N67W ENHANCING SHOWER ACTIVITY NEAR A TROPICAL WAVE E OF THE LESSER ANTILLES. SEE TROPICAL WAVE SECTION FOR MORE DETAILS. THE REMAINDER OF THE BASIN IS DOMINATED BY BROAD SURFACE RIDGING AROUND A 1031 MB HIGH NEAR 40N34W PROVIDING FAIR CONDITIONS. ALOFT...AN UPPER LEVEL RIDGE IS ALONG 33W WITH AN UPPER LEVEL TROUGH JUST W OF THE CANARY ISLANDS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON 000 AXNT20 KNHC 062347 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT WED JUL 06 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2315 UTC. ...TROPICAL WAVES... TROPICAL WAVE IN THE CENTRAL TROPICAL ATLC EXTENDS FROM 11N40W TO 4N43W MOVING W 10-15 KT. WHILE THIS WAVE IS LOW AMPLITUDE AND MAINLY EMBEDDED WITHIN THE ITCZ...A TRACKABLE AND COHERENT FEATURE CAN BE TRACED BACK TO AFRICA. CURRENTLY SCATTERED MODERATE/STRONG CONVECTION IS FROM 4N-10N BETWEEN 40W-50W. TROPICAL WAVE APPROACHING THE LESSER ANTILLES EXTENDS FROM 20N56W TO 13N59W MOVING W 15-20 KT. THE WAVE PRECEDES A LARGE SURGE OF DEEP LAYER MOISTURE EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. SCATTERED MODERATE/STRONG CONVECTION IS MOVING ACROSS THE WINDWARD ISLANDS FROM 12N-18N BETWEEN 57W-62W. SOME OF THIS ACTIVITY MAY BE ASSOCIATED WITH A SURFACE TROUGH JUST W OF THE WAVE AXIS AS WELL AS DIFFLUENCE ALOFT. TROPICAL WAVE IS ACROSS THE YUCATAN PENINSULA EXTENDING FROM 24N85W TO 18N90W MOVING WNW AT 10-15 KT. THE WAVE LIES IN A BROAD AREA OF CYCLONIC FLOW AS WELL AS IN A LARGE AREA OF DEEP LAYER MOISTURE COVERING MUCH OF THE NW CARIBBEAN AND SE GULF OF MEXICO. THE WAVE ALSO IS UNDER AN AREA OF DIFFLUENCE ALOFT FURTHER SUPPORTING CONVECTION. NUMEROUS STRONG CONVECTION IS OVER THE YUCATAN...GUATEMALA...AND BELIZE FROM 16N-19N BETWEEN 88W-91W. SCATTERED MODERATE/STRONG CONVECTION IS FROM 19N-23N BETWEEN 86W-90W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA FROM THE PRIME MERIDIAN AT 21N ALONG 16N12W 11N20W. THE ITCZ CONTINUES FROM 11N20W ALONG 10N30W 9N39W 4N53W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS FROM 6N-8N BETWEEN 34W-36W. ISOLATED MODERATE/STRONG CONVECTION IS FROM 3N-9N BETWEEN 50W-55W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL LOW CONTINUES TO SPIN OVER THE GULF OF MEXICO THIS EVENING NEAR 27N91W WITH TROUGH AXIS EXTENDING FROM CENTRAL ALABAMA TO THE BAY OF CAMPECHE. DRY AIR IS WRAPPING AROUND THE WRN SIDE OF THE UPPER TROUGH MAINTAINING FAIR SURFACE CONDITIONS W OF 87W BESIDES A FEW ISOLATED SHOWERS/THUNDERSTORMS ACROSS LOUISIANA AND ERN TEXAS. THE ERN GULF IS EXPERIENCING MOIST CONDITIONS WITH A LARGE AREA OF DEEP LAYER MOISTURE COVERING THE SE GULF EXTENDING FROM THE WRN ATLC AND NW CARIBBEAN. SOME OF THIS IS ASSOCIATED WITH A TROPICAL WAVE ACROSS THE YUCATAN PENINSULA. SEE TROPICAL WAVE SECTION FOR MORE DETAILS. A SURFACE TROUGH IS E OF THE FLORIDA PENINSULA SUPPORTING SHOWER ACTIVITY AS WELL. THIS AREA ALSO LIES UNDERNEATH THE DIFFLUENT SIDE OF THE UPPER TROUGH WHICH IS HELPING ENHANCE ACTIVITY. THE COMBINATION OF THESE FEATURES IS SUPPORTING A WIDE AREA OF SHOWERS/THUNDERSTORMS ACROSS CUBA...THE STRAITS OF FLORIDA...AND SRN FLORIDA S OF 28N E OF 85W. A FEW SHOWERS/THUNDERSTORMS ARE ALSO OVER NRN FLORIDA. EXPECT MOIST CONDITIONS TO REMAIN OVER THE ERN GULF AS THE TROPICAL WAVE MOVES WNW...AND THE SURFACE TROUGH E OF THE BASIN MOVES W. THE UPPER LOW IS ALSO EXPECTED TO REMAIN RELATIVELY STATIONARY PLACING THE ERN GULF UNDER A DIFFLUENT ZONE. CARIBBEAN SEA... THE NW CARIBBEAN REMAINS UNDER ENHANCED DEEP LAYER MOISTURE STILL REMAINING FROM A TROPICAL WAVE THAT IS NOW OVER THE YUCATAN PENINSULA. CURRENTLY STRONG SHOWERS/THUNDERSTORMS ARE ACROSS MUCH OF CUBA WITH SOME SLIGHTLY LIGHTER ACTIVITY S OF THE ISLAND N OF 18N BETWEEN 79W-85W. ALOFT...AN UPPER LEVEL RIDGE IS CENTERED S OF CUBA NEAR 20N82W WITH AXIS EXTENDING TO THE NE. DRY AIR IS WRAPPING AROUND THE SE SIDE OF THE RIDGE PROVIDING FAIR CONDITIONS ACROSS THE SW AND CENTRAL CARIBBEAN. THIS IS PROVIDING SOME BRIEF RELIEF TO HISPANIOLA WHERE RAINFALL AMOUNTS HAVE BEEN REPORTED UP TO 8 INCHES OVER THE PAST 24 HOURS. AN AREA OF SHOWERS/THUNDERSTORMS IS IN THE FAR SW CARIBBEAN S OF 12N W OF 79W INFLUENCED BY THE MONSOON TROUGH EXTENDING ACROSS COSTA RICA TO NRN COLOMBIA. THE ERN CARIBBEAN IS ALSO UNDER MOIST CONDITIONS AS AN AREA OF DEEP LAYER MOISTURE MOVES INTO THE AREA FROM THE WRN TROPICAL ATLC. SOME OF THIS MOISTURE IS ASSOCIATED WITH A SURFACE TROUGH EXTENDING FROM 15N60W TO 10N64W...AND WITH A TROPICAL WAVE STILL E OF THE ISLANDS. STRONG SHOWERS/THUNDERSTORMS ARE MOVING ACROSS THE WINDWARD ISLANDS FROM 12N-17N E OF 63W WITH MORE ISOLATED ACTIVITY FROM 12N-16N BETWEEN 63W-69W. SOME OF THIS PRECIPITATION IS ENHANCED BY DIFFLUENCE ALOFT AROUND AN UPPER LEVEL TROUGH IN THE CENTRAL ATLC THAT EXTENDS INTO THE NE CARIBBEAN. EXPECT MOIST CONDITIONS TO CONTINUE OVER THE ERN CARIBBEAN AND MOVE INTO THE CENTRAL BASIN AS THE SURFACE TROUGH AND TROPICAL WAVE MOVE WWD. ATLANTIC OCEAN... DESPITE UPPER LEVEL RIDGING COVERING THE FAR W ATLC...A SURFACE TROUGH EXTENDING OFF THE E COAST OF FLORIDA FROM NEAR 28N78W TO 23N71W IS SUPPORTING A LARGE AREA OF SHOWERS/THUNDERSTORMS S OF 28N W OF 74W WITH THE STRONGEST ACTIVITY OVER ERN CUBA. TO THE E...AN UPPER LEVEL TROUGH EXTENDS FROM NEAR 36N46W TO 19N67W ENHANCING SHOWER ACTIVITY NEAR A TROPICAL WAVE E OF THE LESSER ANTILLES. SEE TROPICAL WAVE SECTION FOR MORE DETAILS. THE REMAINDER OF THE BASIN IS DOMINATED BY BROAD SURFACE RIDGING AROUND A 1031 MB HIGH NEAR 40N34W PROVIDING FAIR CONDITIONS. ALOFT...AN UPPER LEVEL RIDGE IS ALONG 33W WITH AN UPPER LEVEL TROUGH JUST W OF THE CANARY ISLANDS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON