000 AXNT20 KNHC 052351 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT TUE JUL 05 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 20N46W TO 11N49W MOVING W NEAR 20 KT. THE WAVE REMAINS WELL-DEFINED IN SATELLITE IMAGERY WITH A CLASSIC INVERTED-V STRUCTURE IN THE LOW LEVEL CLOUDS. THE WAVE PRECEDES A LARGE SURGE OF DEEP LAYER MOISTURE THAT EXTENDS TO NEAR 25N. HOWEVER...DEEP CONVECTION IS STILL LACKING NEAR THE WAVE AXIS. TROPICAL WAVE IS ACROSS THE NW CARIBBEAN FROM WRN CUBA NEAR 22N81W TO ERN HONDURAS NEAR 15N85W MOVING WNW NEAR 10 KT. THE WAVE LIES UNDERNEATH A LARGE AREA OF DEEP LAYER MOISTURE COVERING MUCH OF THE CENTRAL AND NW CARIBBEAN. THE WAVE ALSO IS UNDER AN AREA OF DIFFLUENCE ALOFT FURTHER SUPPORTING CONVECTION. IT IS HARD TO SAY WHAT CONVECTION IS MORE ASSOCIATED WITH THE WAVE OR THE UPPER LEVEL INFLUENCE. CURRENTLY SCATTERED MODERATE/STRONG CONVECTION IS ACROSS HONDURAS FROM 14N-17N BETWEEN 84W-89W...ACROSS THE YUCATAN PENINSULA FROM 16N-22N BETWEEN 87W-91W...AND FROM THE FLORIDA STRAITS FROM 23N-25N BETWEEN 79W-83W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS ACROSS THE NW CARIBBEAN FROM 18N-21N BETWEEN 80W-87W. OTHER CONVECTION IS THE AREA WILL BE DISCUSSED IN THE CARIBBEAN SEA SECTION. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA FROM THE PRIME MERIDIAN AT 22N ALONG 25N5W 18N13W 12N16W 10N22W. THE ITCZ CONTINUES FROM 10N22W ALONG 8N34W 6N43W. A SURFACE TROUGH IS E OF THE CENTRAL ATLC TROPICAL WAVE ALONG 13N54W 9N61W THAT FORMED FROM A PERTURBATION WITHIN THE ITCZ. SCATTERED MODERATE/STRONG CONVECTION IS MAINLY S OF THE TROUGH AXIS FROM 10N-13N BETWEEN 50W-60W. ELSEWHERE...ISOLATED MODERATE/STRONG CONVECTION IS FROM 3N-10N BETWEEN 32W-39W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL LOW CONTINUES TO SPIN OVER THE GULF OF MEXICO THIS EVENING NEAR 26N91W WITH TROUGH AXIS EXTENDING FROM CENTRAL ALABAMA TO THE BAY OF CAMPECHE. THE UPPER TROUGH IS SUPPORTING A SURFACE TROUGH ALONG 89W FROM 25N-27N. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE E OF THE TROUGH AXIS FROM 24N-28N BETWEEN 85W-88W. AN AREA OF DIFFLUENT FLOW AROUND THE NRN PORTION OF THE UPPER TROUGH ALONG WITH DAYTIME HEATING IS CONTINUING TO SUPPORT A LINE OF STRONG SHOWERS/THUNDERSTORMS ALONG THE NRN GULF COAST FROM THE WRN FLORIDA PANHANDLE TO ERN TEXAS. SCATTERED SHOWERS/THUNDERSTORMS ARE ALSO ACROSS THE FLORIDA STRAITS AND THE YUCATAN PENINSULA INFLUENCED BY DEEP LAYER MOISTURE ACROSS THE NW CARIBBEAN AND A TROPICAL WAVE ALSO IN THE NW CARIBBEAN. WEAK SURFACE RIDGING AROUND A 1016 MB HIGH NEAR TAMPICO MEXICO AT 22N98W IS PROVIDING FAIR WEATHER AND LIGHT WINDS ACROSS THE WRN GULF. EXPECT THE SURFACE TROUGH TO CONTINUE TO DRIFT W WITH ISOLATED SHOWERS/THUNDERSTORMS. EXPECT SHOWER ACTIVITY TO INCREASE OVER THE SE GULF AS THE TROPICAL WAVE AND ASSOCIATED DEEP LAYER MOISTURE OVER THE WNW CARIBBEAN CONTINUES TO DRIFT NW. CARIBBEAN SEA... MOIST CONDITIONS ARE ACROSS MUCH OF THE NW CARIBBEAN THIS EVENING INFLUENCED BY A TROPICAL WAVE EXTENDING FROM WRN CUBA TO ERN HONDURAS...AND ENHANCED DEEP LAYER MOISTURE N OF 16N W OF 71W. SEE TROPICAL WAVE SECTION FOR MORE DETAILS ON THE WAVE. THIS AREA ALSO LIES UNDERNEATH A STRETCH OF DIFFLUENCE ALOFT BETWEEN AN UPPER LEVEL TROUGH OVER THE GULF OF MEXICO AND AN UPPER LEVEL RIDGE CENTERED S OF CENTRAL CUBA. THIS COMBINATION IS SUPPORTING SHOWERS/THUNDERSTORMS N OF 18N W OF 75W ACROSS THE YUCATAN PENINSULA...MUCH OF CUBA...AND JAMAICA. STRONGER ACTIVITY IS OVER ERN CUBA DUE TO THE INFLUENCE OF A SURFACE TROUGH EXTENDING FROM THE WRN ATLC TO NEAR 22N77W. SCATTERED SHOWERS/THUNDERSTORMS ARE ALSO OVER NICARAGUA AND HONDURAS INFLUENCED BY THE TROPICAL WAVE AS WELL AS THE MONSOON TROUGH THAT EXTENDS FROM THE E PACIFIC ACROSS NICARAGUA TO NRN COLOMBIA. THE REMAINDER OF THE BASIN IS UNDER MOSTLY FAIR CONDITIONS EXCEPT FOR A FEW ISOLATED SHOWERS/THUNDERSTORMS OVER HISPANIOLA DUE TO DRY AIR ALOFT AROUND THE UPPER LEVEL RIDGE CENTERED NEAR CUBA. EXPECT MOIST CONDITIONS TO REMAIN OVER THE NW CARIBBEAN OVER THE NEXT 24 HOURS AS THE WAVE MOVES WNW. SHOWER ACTIVITY MAY FLARE UP OVER THE SE CARIBBEAN AS MOISTURE ASSOCIATED WITH A SURFACE TROUGH EMBEDDED IN THE ITCZ MOVES WWD. ATLANTIC OCEAN... DESPITE UPPER LEVEL RIDGING COVERING THE FAR W ATLC...A SURFACE TROUGH EXTENDING ACROSS THE CENTRAL BAHAMAS FROM NEAR 27N73W TO 22N77W IS SUPPORTING A LARGE AREA OF SHOWERS/THUNDERSTORMS S OF 26N W OF 66W WITH THE STRONGEST ACTIVITY OVER ERN CUBA. TO THE E...AN UPPER LEVEL LOW IS SPINNING NEAR 26N51W SUPPORTING A WEAK SURFACE TROUGH ALONG 53W FROM 25N-27N. ISOLATED SHOWERS ARE NEAR THE TROUGH FROM 24N-31N BETWEEN 27W-53W. A SHORTWAVE UPPER TROUGH EXTENDS OFF THE MAIN CIRCULATION OF THE UPPER LOW SUPPORTING ISOLATED SHOWERS/THUNDERSTORMS FROM 23N-28N BETWEEN 63W-69W. THE REMAINDER OF THE BASIN IS DOMINATED BY BROAD SURFACE RIDGING AROUND A 1030 MB HIGH NEAR 37N38W PROVIDING FAIR CONDITIONS. ALOFT...AN UPPER LEVEL RIDGE IS ALONG 34W WITH A WEAK UPPER TROUGH EXTENDING FROM THE AZORES TO THE CANARY ISLANDS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON 000 AXNT20 KNHC 052351 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 PM EDT TUE JUL 05 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 20N46W TO 11N49W MOVING W NEAR 20 KT. THE WAVE REMAINS WELL-DEFINED IN SATELLITE IMAGERY WITH A CLASSIC INVERTED-V STRUCTURE IN THE LOW LEVEL CLOUDS. THE WAVE PRECEDES A LARGE SURGE OF DEEP LAYER MOISTURE THAT EXTENDS TO NEAR 25N. HOWEVER...DEEP CONVECTION IS STILL LACKING NEAR THE WAVE AXIS. TROPICAL WAVE IS ACROSS THE NW CARIBBEAN FROM WRN CUBA NEAR 22N81W TO ERN HONDURAS NEAR 15N85W MOVING WNW NEAR 10 KT. THE WAVE LIES UNDERNEATH A LARGE AREA OF DEEP LAYER MOISTURE COVERING MUCH OF THE CENTRAL AND NW CARIBBEAN. THE WAVE ALSO IS UNDER AN AREA OF DIFFLUENCE ALOFT FURTHER SUPPORTING CONVECTION. IT IS HARD TO SAY WHAT CONVECTION IS MORE ASSOCIATED WITH THE WAVE OR THE UPPER LEVEL INFLUENCE. CURRENTLY SCATTERED MODERATE/STRONG CONVECTION IS ACROSS HONDURAS FROM 14N-17N BETWEEN 84W-89W...ACROSS THE YUCATAN PENINSULA FROM 16N-22N BETWEEN 87W-91W...AND FROM THE FLORIDA STRAITS FROM 23N-25N BETWEEN 79W-83W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS ACROSS THE NW CARIBBEAN FROM 18N-21N BETWEEN 80W-87W. OTHER CONVECTION IS THE AREA WILL BE DISCUSSED IN THE CARIBBEAN SEA SECTION. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA FROM THE PRIME MERIDIAN AT 22N ALONG 25N5W 18N13W 12N16W 10N22W. THE ITCZ CONTINUES FROM 10N22W ALONG 8N34W 6N43W. A SURFACE TROUGH IS E OF THE CENTRAL ATLC TROPICAL WAVE ALONG 13N54W 9N61W THAT FORMED FROM A PERTURBATION WITHIN THE ITCZ. SCATTERED MODERATE/STRONG CONVECTION IS MAINLY S OF THE TROUGH AXIS FROM 10N-13N BETWEEN 50W-60W. ELSEWHERE...ISOLATED MODERATE/STRONG CONVECTION IS FROM 3N-10N BETWEEN 32W-39W. ...DISCUSSION... GULF OF MEXICO... AN UPPER LEVEL LOW CONTINUES TO SPIN OVER THE GULF OF MEXICO THIS EVENING NEAR 26N91W WITH TROUGH AXIS EXTENDING FROM CENTRAL ALABAMA TO THE BAY OF CAMPECHE. THE UPPER TROUGH IS SUPPORTING A SURFACE TROUGH ALONG 89W FROM 25N-27N. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE E OF THE TROUGH AXIS FROM 24N-28N BETWEEN 85W-88W. AN AREA OF DIFFLUENT FLOW AROUND THE NRN PORTION OF THE UPPER TROUGH ALONG WITH DAYTIME HEATING IS CONTINUING TO SUPPORT A LINE OF STRONG SHOWERS/THUNDERSTORMS ALONG THE NRN GULF COAST FROM THE WRN FLORIDA PANHANDLE TO ERN TEXAS. SCATTERED SHOWERS/THUNDERSTORMS ARE ALSO ACROSS THE FLORIDA STRAITS AND THE YUCATAN PENINSULA INFLUENCED BY DEEP LAYER MOISTURE ACROSS THE NW CARIBBEAN AND A TROPICAL WAVE ALSO IN THE NW CARIBBEAN. WEAK SURFACE RIDGING AROUND A 1016 MB HIGH NEAR TAMPICO MEXICO AT 22N98W IS PROVIDING FAIR WEATHER AND LIGHT WINDS ACROSS THE WRN GULF. EXPECT THE SURFACE TROUGH TO CONTINUE TO DRIFT W WITH ISOLATED SHOWERS/THUNDERSTORMS. EXPECT SHOWER ACTIVITY TO INCREASE OVER THE SE GULF AS THE TROPICAL WAVE AND ASSOCIATED DEEP LAYER MOISTURE OVER THE WNW CARIBBEAN CONTINUES TO DRIFT NW. CARIBBEAN SEA... MOIST CONDITIONS ARE ACROSS MUCH OF THE NW CARIBBEAN THIS EVENING INFLUENCED BY A TROPICAL WAVE EXTENDING FROM WRN CUBA TO ERN HONDURAS...AND ENHANCED DEEP LAYER MOISTURE N OF 16N W OF 71W. SEE TROPICAL WAVE SECTION FOR MORE DETAILS ON THE WAVE. THIS AREA ALSO LIES UNDERNEATH A STRETCH OF DIFFLUENCE ALOFT BETWEEN AN UPPER LEVEL TROUGH OVER THE GULF OF MEXICO AND AN UPPER LEVEL RIDGE CENTERED S OF CENTRAL CUBA. THIS COMBINATION IS SUPPORTING SHOWERS/THUNDERSTORMS N OF 18N W OF 75W ACROSS THE YUCATAN PENINSULA...MUCH OF CUBA...AND JAMAICA. STRONGER ACTIVITY IS OVER ERN CUBA DUE TO THE INFLUENCE OF A SURFACE TROUGH EXTENDING FROM THE WRN ATLC TO NEAR 22N77W. SCATTERED SHOWERS/THUNDERSTORMS ARE ALSO OVER NICARAGUA AND HONDURAS INFLUENCED BY THE TROPICAL WAVE AS WELL AS THE MONSOON TROUGH THAT EXTENDS FROM THE E PACIFIC ACROSS NICARAGUA TO NRN COLOMBIA. THE REMAINDER OF THE BASIN IS UNDER MOSTLY FAIR CONDITIONS EXCEPT FOR A FEW ISOLATED SHOWERS/THUNDERSTORMS OVER HISPANIOLA DUE TO DRY AIR ALOFT AROUND THE UPPER LEVEL RIDGE CENTERED NEAR CUBA. EXPECT MOIST CONDITIONS TO REMAIN OVER THE NW CARIBBEAN OVER THE NEXT 24 HOURS AS THE WAVE MOVES WNW. SHOWER ACTIVITY MAY FLARE UP OVER THE SE CARIBBEAN AS MOISTURE ASSOCIATED WITH A SURFACE TROUGH EMBEDDED IN THE ITCZ MOVES WWD. ATLANTIC OCEAN... DESPITE UPPER LEVEL RIDGING COVERING THE FAR W ATLC...A SURFACE TROUGH EXTENDING ACROSS THE CENTRAL BAHAMAS FROM NEAR 27N73W TO 22N77W IS SUPPORTING A LARGE AREA OF SHOWERS/THUNDERSTORMS S OF 26N W OF 66W WITH THE STRONGEST ACTIVITY OVER ERN CUBA. TO THE E...AN UPPER LEVEL LOW IS SPINNING NEAR 26N51W SUPPORTING A WEAK SURFACE TROUGH ALONG 53W FROM 25N-27N. ISOLATED SHOWERS ARE NEAR THE TROUGH FROM 24N-31N BETWEEN 27W-53W. A SHORTWAVE UPPER TROUGH EXTENDS OFF THE MAIN CIRCULATION OF THE UPPER LOW SUPPORTING ISOLATED SHOWERS/THUNDERSTORMS FROM 23N-28N BETWEEN 63W-69W. THE REMAINDER OF THE BASIN IS DOMINATED BY BROAD SURFACE RIDGING AROUND A 1030 MB HIGH NEAR 37N38W PROVIDING FAIR CONDITIONS. ALOFT...AN UPPER LEVEL RIDGE IS ALONG 34W WITH A WEAK UPPER TROUGH EXTENDING FROM THE AZORES TO THE CANARY ISLANDS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON