000 AXNT20 KNHC 271129 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT MON JUN 27 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 1115 UTC. ...TROPICAL WAVES... A TROPICAL WAVE IS ACROSS THE CENTRAL ATLC ALONG 14N33W TO 5N35W MOVING W NEAR 15 KT. THE WAVE ALIGNS WITH CYCLONIC FLOW CAPTURED BY PREVIOUS SCATTEROMETER DATA. THE WAVE IS OF THE WRN SIDE OF A SURGE OF DEEP LAYER MOISTURE EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. NO DEEP CONVECTION IS CURRENTLY ASSOCIATED WITH THIS WAVE. A TROPICAL WAVE EXTENDS ACROSS THE WINDWARD ISLANDS FROM 17N61W TO 10N64W MOVING W NEAR 15 KT. THE WAVE LIES ON THE ERN EDGE OF AN AREA OF MAXIMUM DEEP LAYER MOISTURE THAT HAS MOVED OVER THE ERN CARIBBEAN. ISOLATED MODERATE CONVECTION IS E OF THE WAVE AXIS FROM 13N-17N BETWEEN 59W-67W. SCATTERED MODERATE/STRONG CONVECTION IS OVER THE VIRGIN ISLANDS FROM 17N-19N BETWEEN 62W-65W. THIS WAVE WILL CONTINUE TO BRING MOISTURE AND PRECIPITATION TO THE ERN CARIBBEAN OVER THE NEXT 24 HOURS...AND MAY BEGIN TO INTERACT WITH AN UPPER LEVEL LOW MOVING S TOWARDS THE DOMINICAN REPUBLIC WHICH WOULD SUPPORT MORE CONVECTION. A TROPICAL WAVE IS OVER THE CENTRAL GULF AND ERN BAY OF CAMPECHE ALONG 25N89W TO 15N92W DRIFTING WNW AT 5-10 KT. THE WAVE LIES IN A LARGE AREA OF DEEP LAYER MOISTURE PRESENT ACROSS THE NW CARIBBEAN AND SRN GULF. BROAD CYCLONIC FLOW IS ABOUT THE WAVE AXIS INDICATED BY SATELLITE IMAGERY...AND APPEARS TO BE CONCENTRATED ALONG THE WAVE AXIS NEAR 20N WHERE A SURFACE LOW MAY BE FORMING. NUMEROUS STRONG CONVECTION IS S OF SRN MEXICO FROM 13N-16N BETWEEN 91W-97W. SCATTERED MODERATE/STRONG CONVECTION IS OVER THE YUCATAN PENINSULA AND BAY OF CAMPECHE FROM 15N-20N BETWEEN 88W-96W...AND FROM 20N-22N BETWEEN 85-88W. ISOLATED MODERATE CONVECTION IS OVER THE ERN GULF FROM 25N-28N BETWEEN 82W-88W. THE WAVE WILL LIKELY KEEP MOISTURE OVER MUCH OF THE SRN GULF OVER THE NEXT COUPLE OF DAYS. A LOW PRESSURE CIRCULATION IS ALSO EXPECTED TO FORM AS THE WAVE DRIFTS WNW INTO THE BAY OF CAMPECHE. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA FROM THE PRIME MERIDIAN AT 21N ALONG 22N11W TO THE COAST AT 12N16W AND OVER WATER TO 9N19W. THE ITCZ AXIS CONTINUES FROM 9N19W ALONG 6N34W 6N46W 4N56W. AN EMBEDDED SURFACE TROUGH IS ANALYZED ALONG 44W FROM 7N-10N. ISOLATED MODERATE/STRONG CONVECTION IS OFF THE W COAST OF AFRICA FROM 6N-12N BETWEEN 12N-18N...AND WITHIN 60 NM EITHER SIDE OF THE AXIS BETWEEN 43W-51W. ...DISCUSSION... GULF OF MEXICO... A LARGE AREA OF DEEP LAYER MOISTURE ASSOCIATED WITH A TROPICAL WAVE SITS OVER THE SRN GULF OF MEXICO SUPPORTING SCATTERED SHOWERS/THUNDERSTORMS IN THE ERN GULF FROM 25N-28N BETWEEN 82W-89W. SCATTERED SHOWERS/THUNDERSTORMS ARE ALSO OVER THE BAY OF CAMPECHE S OF 22N. SEE TROPICAL WAVE SECTION FOR MORE DETAILS. THE WAVE IS EXPECTED TO DRIFT WNW WITH A POSSIBLE LOW FORMING ALONG THE AXIS OVER THE SRN BAY OF CAMPECHE. ENHANCED MOISTURE EXTENDS OVER MUCH OF THE FLORIDA PENINSULA INCREASING THE PROBABILITY OF SHOWER ACTIVITY TODAY. ALOFT...A NARROW SHORTWAVE UPPER LEVEL TROUGH CONTINUES TO EXTEND FROM THE FLORIDA PANHANDLE TO CENTRAL MEXICO NEAR 23N102W WITH AN UPPER LEVEL RIDGE EXTENDING FROM THE WRN CARIBBEAN AND INTO THE SE GULF. STRONG DRY AIR AND SUBSIDENCE IS OVER THE NW GULF MAINTAINING FAIR CONDITIONS. EXPECT MOIST CONDITIONS TO REMAIN ACROSS THE MAJORITY OF THE BASIN OVER THE NEXT COUPLE OF DAYS. CARIBBEAN SEA... ENHANCED MOISTURE REMAINS OVER THE WRN CARIBBEAN IN THE WAKE OF THE TROPICAL WAVE THAT IS NOW OVER THE ERN BAY OF CAMPECHE. ISOLATED SHOWERS/POSSIBLE THUNDERSTORMS ARE W OF 82W...WHILE A FEW MORE CONCENTRATED CLUSTERS OF ACTIVITY ARE OVER THE YUCATAN CHANNEL. A CLUSTER OF SHOWERS/THUNDERSTORMS IS IN THE FAR SW CARIBBEAN OFF THE COAST OF PANAMA FROM 9N-11N BETWEEN 80W-82W INFLUENCED BY THE MONSOON TROUGH EXTENDING FROM THE E PACIFIC ACROSS COSTA RICA TO NRN COLOMBIA. A LARGE AREA OF STRONG SHOWERS/THUNDERSTORMS IS OVER NRN COLOMBIA NEAR THE WRN EXTENT OF THE MONSOON TROUGH. THE CENTRAL CARIBBEAN BETWEEN 73W-82W IS UNDER MOSTLY FAIR CONDITIONS DUE TO AN AREA OF DRY AIR ALOFT THAT IS BEING WRAPPED AROUND THE W SIDE OF AN UPPER LEVEL LOW CURRENTLY JUST N OF THE DOMINICAN REPUBLIC NEAR 20N69W. MOIST SWLY FLOW ALOFT COVERS THE ERN CARIBBEAN WHICH IS HELPING ENHANCE CONVECTION NEAR A TROPICAL WAVE EXTENDING ACROSS THE WINDWARD ISLANDS. SEE TROPICAL WAVE SECTION ABOVE FOR MORE DETAIL. THE UPPER LOW IS ALSO SUPPORTING SCATTERED SHOWERS/THUNDERSTORMS N OF 17N BETWEEN 63W-71W. AS THE UPPER LOW MOVES SW...AND THE WAVE MOVES W PLACING IT UNDER DIFFLUENCE ALOFT...STRONGER SHOWER/THUNDERSTORM ACTIVITY COULD FLARE UP OVER THE ERN AND CENTRAL CARIBBEAN. ATLANTIC OCEAN... AN UPPER LEVEL TROUGH CONTINUES TO SIT OVER THE ERN SEABOARD ALLOWING FOR MOIST SWLY FLOW TO COVER MUCH OF THE WRN ATLC. SCATTERED SHOWERS/THUNDERSTORMS ARE FROM 27N-30N BETWEEN 77W-81W...AND N OF 29N BETWEEN 71W-73W. ISOLATED SHOWERS/POSSIBLE THUNDERSTORMS ARE ALSO N OF 25N BETWEEN 73W-79W. A NARROW UPPER RIDGE EXTENDS FROM THE SE GULF TO NEAR 32N67W SANDWICHED BETWEEN THE AFOREMENTIONED UPPER TROUGH AND AN UPPER LEVEL LOW N OF THE DOMINICAN REPUBLIC NEAR 20N69W. THE UPPER LOW SUPPORTS SCATTERED SHOWERS/THUNDERSTORMS FROM 17N-23N BETWEEN 67W-71W. A TROPICAL WAVE THAT EXTENDS ACROSS THE WINDWARD ISLANDS IS SUPPORTING SCATTERED SHOWERS/THUNDERSTORMS FROM THE VIRGIN ISLANDS TO 19N BETWEEN 61W-65W. FARTHER E...SURFACE RIDGING DOMINATES THE MAJORITY OF THE CENTRAL AND ERN TROPICAL ATLC CENTERED AROUND A 1026 MB HIGH NEAR 33N53W SUPPORTED BY AN UPPER LEVEL RIDGE CENTERED NEAR 32N47W. A LONGWAVE UPPER TROUGH IS OVER THE ERN ATLC ALONG 20W SUPPORTING A WEAK SURFACE TROUGH THAT EXTENDS ALONG 31N27W TO 28N32W. POSSIBLE ISOLATED SHOWER ARE WITHIN 60 NM SE OF THE AXIS. A SAHARAN AIR LAYER CONSISTING OF DRY AND DUSTY AIR CONTINUES TO MOVE OVER THE CENTRAL ATLC BETWEEN 40W-60W...AS WELL AS N OF THE TROPICAL WAVE MOVING IN THE CENTRAL ATLC. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON 000 AXNT20 KNHC 271129 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT MON JUN 27 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 1115 UTC. ...TROPICAL WAVES... A TROPICAL WAVE IS ACROSS THE CENTRAL ATLC ALONG 14N33W TO 5N35W MOVING W NEAR 15 KT. THE WAVE ALIGNS WITH CYCLONIC FLOW CAPTURED BY PREVIOUS SCATTEROMETER DATA. THE WAVE IS OF THE WRN SIDE OF A SURGE OF DEEP LAYER MOISTURE EVIDENT IN TOTAL PRECIPITABLE WATER IMAGERY. NO DEEP CONVECTION IS CURRENTLY ASSOCIATED WITH THIS WAVE. A TROPICAL WAVE EXTENDS ACROSS THE WINDWARD ISLANDS FROM 17N61W TO 10N64W MOVING W NEAR 15 KT. THE WAVE LIES ON THE ERN EDGE OF AN AREA OF MAXIMUM DEEP LAYER MOISTURE THAT HAS MOVED OVER THE ERN CARIBBEAN. ISOLATED MODERATE CONVECTION IS E OF THE WAVE AXIS FROM 13N-17N BETWEEN 59W-67W. SCATTERED MODERATE/STRONG CONVECTION IS OVER THE VIRGIN ISLANDS FROM 17N-19N BETWEEN 62W-65W. THIS WAVE WILL CONTINUE TO BRING MOISTURE AND PRECIPITATION TO THE ERN CARIBBEAN OVER THE NEXT 24 HOURS...AND MAY BEGIN TO INTERACT WITH AN UPPER LEVEL LOW MOVING S TOWARDS THE DOMINICAN REPUBLIC WHICH WOULD SUPPORT MORE CONVECTION. A TROPICAL WAVE IS OVER THE CENTRAL GULF AND ERN BAY OF CAMPECHE ALONG 25N89W TO 15N92W DRIFTING WNW AT 5-10 KT. THE WAVE LIES IN A LARGE AREA OF DEEP LAYER MOISTURE PRESENT ACROSS THE NW CARIBBEAN AND SRN GULF. BROAD CYCLONIC FLOW IS ABOUT THE WAVE AXIS INDICATED BY SATELLITE IMAGERY...AND APPEARS TO BE CONCENTRATED ALONG THE WAVE AXIS NEAR 20N WHERE A SURFACE LOW MAY BE FORMING. NUMEROUS STRONG CONVECTION IS S OF SRN MEXICO FROM 13N-16N BETWEEN 91W-97W. SCATTERED MODERATE/STRONG CONVECTION IS OVER THE YUCATAN PENINSULA AND BAY OF CAMPECHE FROM 15N-20N BETWEEN 88W-96W...AND FROM 20N-22N BETWEEN 85-88W. ISOLATED MODERATE CONVECTION IS OVER THE ERN GULF FROM 25N-28N BETWEEN 82W-88W. THE WAVE WILL LIKELY KEEP MOISTURE OVER MUCH OF THE SRN GULF OVER THE NEXT COUPLE OF DAYS. A LOW PRESSURE CIRCULATION IS ALSO EXPECTED TO FORM AS THE WAVE DRIFTS WNW INTO THE BAY OF CAMPECHE. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS ACROSS AFRICA FROM THE PRIME MERIDIAN AT 21N ALONG 22N11W TO THE COAST AT 12N16W AND OVER WATER TO 9N19W. THE ITCZ AXIS CONTINUES FROM 9N19W ALONG 6N34W 6N46W 4N56W. AN EMBEDDED SURFACE TROUGH IS ANALYZED ALONG 44W FROM 7N-10N. ISOLATED MODERATE/STRONG CONVECTION IS OFF THE W COAST OF AFRICA FROM 6N-12N BETWEEN 12N-18N...AND WITHIN 60 NM EITHER SIDE OF THE AXIS BETWEEN 43W-51W. ...DISCUSSION... GULF OF MEXICO... A LARGE AREA OF DEEP LAYER MOISTURE ASSOCIATED WITH A TROPICAL WAVE SITS OVER THE SRN GULF OF MEXICO SUPPORTING SCATTERED SHOWERS/THUNDERSTORMS IN THE ERN GULF FROM 25N-28N BETWEEN 82W-89W. SCATTERED SHOWERS/THUNDERSTORMS ARE ALSO OVER THE BAY OF CAMPECHE S OF 22N. SEE TROPICAL WAVE SECTION FOR MORE DETAILS. THE WAVE IS EXPECTED TO DRIFT WNW WITH A POSSIBLE LOW FORMING ALONG THE AXIS OVER THE SRN BAY OF CAMPECHE. ENHANCED MOISTURE EXTENDS OVER MUCH OF THE FLORIDA PENINSULA INCREASING THE PROBABILITY OF SHOWER ACTIVITY TODAY. ALOFT...A NARROW SHORTWAVE UPPER LEVEL TROUGH CONTINUES TO EXTEND FROM THE FLORIDA PANHANDLE TO CENTRAL MEXICO NEAR 23N102W WITH AN UPPER LEVEL RIDGE EXTENDING FROM THE WRN CARIBBEAN AND INTO THE SE GULF. STRONG DRY AIR AND SUBSIDENCE IS OVER THE NW GULF MAINTAINING FAIR CONDITIONS. EXPECT MOIST CONDITIONS TO REMAIN ACROSS THE MAJORITY OF THE BASIN OVER THE NEXT COUPLE OF DAYS. CARIBBEAN SEA... ENHANCED MOISTURE REMAINS OVER THE WRN CARIBBEAN IN THE WAKE OF THE TROPICAL WAVE THAT IS NOW OVER THE ERN BAY OF CAMPECHE. ISOLATED SHOWERS/POSSIBLE THUNDERSTORMS ARE W OF 82W...WHILE A FEW MORE CONCENTRATED CLUSTERS OF ACTIVITY ARE OVER THE YUCATAN CHANNEL. A CLUSTER OF SHOWERS/THUNDERSTORMS IS IN THE FAR SW CARIBBEAN OFF THE COAST OF PANAMA FROM 9N-11N BETWEEN 80W-82W INFLUENCED BY THE MONSOON TROUGH EXTENDING FROM THE E PACIFIC ACROSS COSTA RICA TO NRN COLOMBIA. A LARGE AREA OF STRONG SHOWERS/THUNDERSTORMS IS OVER NRN COLOMBIA NEAR THE WRN EXTENT OF THE MONSOON TROUGH. THE CENTRAL CARIBBEAN BETWEEN 73W-82W IS UNDER MOSTLY FAIR CONDITIONS DUE TO AN AREA OF DRY AIR ALOFT THAT IS BEING WRAPPED AROUND THE W SIDE OF AN UPPER LEVEL LOW CURRENTLY JUST N OF THE DOMINICAN REPUBLIC NEAR 20N69W. MOIST SWLY FLOW ALOFT COVERS THE ERN CARIBBEAN WHICH IS HELPING ENHANCE CONVECTION NEAR A TROPICAL WAVE EXTENDING ACROSS THE WINDWARD ISLANDS. SEE TROPICAL WAVE SECTION ABOVE FOR MORE DETAIL. THE UPPER LOW IS ALSO SUPPORTING SCATTERED SHOWERS/THUNDERSTORMS N OF 17N BETWEEN 63W-71W. AS THE UPPER LOW MOVES SW...AND THE WAVE MOVES W PLACING IT UNDER DIFFLUENCE ALOFT...STRONGER SHOWER/THUNDERSTORM ACTIVITY COULD FLARE UP OVER THE ERN AND CENTRAL CARIBBEAN. ATLANTIC OCEAN... AN UPPER LEVEL TROUGH CONTINUES TO SIT OVER THE ERN SEABOARD ALLOWING FOR MOIST SWLY FLOW TO COVER MUCH OF THE WRN ATLC. SCATTERED SHOWERS/THUNDERSTORMS ARE FROM 27N-30N BETWEEN 77W-81W...AND N OF 29N BETWEEN 71W-73W. ISOLATED SHOWERS/POSSIBLE THUNDERSTORMS ARE ALSO N OF 25N BETWEEN 73W-79W. A NARROW UPPER RIDGE EXTENDS FROM THE SE GULF TO NEAR 32N67W SANDWICHED BETWEEN THE AFOREMENTIONED UPPER TROUGH AND AN UPPER LEVEL LOW N OF THE DOMINICAN REPUBLIC NEAR 20N69W. THE UPPER LOW SUPPORTS SCATTERED SHOWERS/THUNDERSTORMS FROM 17N-23N BETWEEN 67W-71W. A TROPICAL WAVE THAT EXTENDS ACROSS THE WINDWARD ISLANDS IS SUPPORTING SCATTERED SHOWERS/THUNDERSTORMS FROM THE VIRGIN ISLANDS TO 19N BETWEEN 61W-65W. FARTHER E...SURFACE RIDGING DOMINATES THE MAJORITY OF THE CENTRAL AND ERN TROPICAL ATLC CENTERED AROUND A 1026 MB HIGH NEAR 33N53W SUPPORTED BY AN UPPER LEVEL RIDGE CENTERED NEAR 32N47W. A LONGWAVE UPPER TROUGH IS OVER THE ERN ATLC ALONG 20W SUPPORTING A WEAK SURFACE TROUGH THAT EXTENDS ALONG 31N27W TO 28N32W. POSSIBLE ISOLATED SHOWER ARE WITHIN 60 NM SE OF THE AXIS. A SAHARAN AIR LAYER CONSISTING OF DRY AND DUSTY AIR CONTINUES TO MOVE OVER THE CENTRAL ATLC BETWEEN 40W-60W...AS WELL AS N OF THE TROPICAL WAVE MOVING IN THE CENTRAL ATLC. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON