000 AXNT20 KNHC 061049 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SAT JUL 06 2013 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 1015 UTC. ...TROPICAL WAVES... TROPICAL WAVE WAS RELOCATED FARTHER EAST TO ALIGN WITH A SURFACE LOW ALONG THE MONSOON TROUGH. AXIS IS CURRENTLY ALONG 19N32W TO A 1012 MB LOW NEAR 7N30W MOVING WEST NEAR 15 KT. THE WAVE IS EMBEDDED WITHIN AN AREA OF SLIGHTLY INCREASED MOISTURE PRESENT IN TOTAL PRECIPITABLE WATER IMAGERY. HOWEVER...A LARGE SAHARAN AIR LAYER SURROUNDS THE WAVE...WHICH IS INHIBITING ANY DEEP CONVECTION NEAR THE AXIS EXCEPT NEAR THE LOW. SCATTERED MODERATE/STRONG CONVECTION IS FROM 5N-10N BETWEEN 30W-34W. TROPICAL WAVE HAS BEEN RELOCATED FARTHER WEST TO THE EASTERN CARIBBEAN ALONG 20N60W TO 11N64W. THIS LOCATION IS WHERE A SURFACE TROUGH WAS ANALYZED ON THE PREVIOUS ANALYSIS. THE LOCATION OF THE WAVE IS BASED ON MODEL POTENTIAL VORTICITY FIELDS WHICH INDICATE A CLEAR WAVE AXIS MOVING WESTWARD OVER THE PAST SEVERAL DAYS TO THE CURRENT LOCATION WHERE IT IS ANALYZED. THE WAVE ALSO COINCIDES WITH A SURGE OF MODERATE MOISTURE PRESENT IN TOTAL PRECIPITABLE WATER IMAGERY. AN AREA OF INCREASED MOISTURE IS ALSO FARTHER EAST WHERE THE WAVE WAS PREVIOUSLY ANALYZED. NO DEEP CONVECTION IS CURRENTLY ASSOCIATED WITH THE WAVE. TROPICAL WAVE PREVIOUSLY MOVING INTO CENTRAL AMERICA HAS NOW DISSIPATED. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE COAST OF MAURITANIA NEAR 19N16W TO 11N23W TO A 1012 MB SURFACE LOW NEAR 7N31W TO 6N38W. THE ITCZ BEGINS NEAR 6N38W AND CONTINUES ALONG 5N46W 6N54W. BESIDES CONVECTION NEAR THE SURFACE LOW ASSOCIATED WITH THE TROPICAL WAVE...SCATTERED MODERATE CONVECTION IS WITHIN 150 NM SOUTH OF THE AXIS BETWEEN 36W-54W. ...DISCUSSION... GULF OF MEXICO... MOIST CONDITIONS REMAIN ACROSS MUCH OF THE GULF OF MEXICO. THIS IS DUE TO A COMBINATION OF MOIST SOUTHERLY TO SOUTHEASTERLY FLOW AT THE SURFACE THROUGHOUT MUCH OF THE AREA...AND MOIST SOUTHWESTERLY AND DIFFLUENT FLOW ALOFT BETWEEN AN UPPER LEVEL TROUGH OVER THE CENTRAL CONUS THAT IS PUSHING INTO THE NW GULF...AND AN UPPER LEVEL RIDGE OVER THE REMAINDER OF THE BASIN EXTENDING FROM THE BAY OF CAMPECHE NEAR 19N96W TO 31N84W. ISOLATED SHOWERS AND POSSIBLE THUNDERSTORMS ARE THROUGHOUT THE AREA WITH SOME AREAS OF STRONGER ACTIVITY. NUMEROUS SHOWERS/SCATTERED THUNDERSTORMS ARE FROM 23N-27N BETWEEN 87W- 91W...FROM 25N-27N BETWEEN 92W-95W...AND FROM 16N-21N BETWEEN 92W-95W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE ALSO NEAR A SURFACE TROUGH IN THE FAR WESTERN GULF ALONG 26N96W TO 19N96W. THE SURFACE TROUGH IS EXPECTED TO DRIFT WEST AND NORTH OVER THE NEXT 24 HOURS WHILE MOIST CONDITIONS WILL CONTINUE TO IMPACT THE BASIN FOR AT LEAST THE NEXT DAY OR SO. CARIBBEAN SEA... MOISTURE FROM THE GULF OF MEXICO IS DRAWN OVER THE NW CARIBBEAN IN NORTHERLY FLOW ALOFT AROUND AN UPPER LEVEL RIDGE OVER THE GULF. ONLY A FEW ISOLATED SHOWERS ARE NORTH OF 19N BETWEEN 78W- 86W. SCATTERED SHOWERS/ISOLATED THUNDERSTORMS ARE IN THE SW CARIBBEAN SOUTH OF 11N BETWEEN 76W-84W ASSOCIATED WITH THE MONSOON TROUGH EXTENDING ALONG 9N TO A 1009 MB SURFACE LOW OVER NORTHERN COLOMBIA. THE REMAINDER OF THE BASIN IS FAIRLY DRY EXCEPT FOR ISOLATED SHOWERS OVER THE NE CORNER FROM 15N-18N EAST OF 71W ASSOCIATED WITH A TROPICAL WAVE THAT HAS BEEN RELOCATED OVER THE EASTERN CARIBBEAN NEAR 62W. ALOFT...A NARROW UPPER TROUGH EXTENDS FROM HAITI TO COSTA RICA...BUT IS ACCOMPANIED BY DRY AIR ALOFT. UPPER LEVEL RIDGING COVERS THE REMAINDER OF THE BASIN ALSO ACCOMPANIED BY DRY AIR ALOFT. TRADEWIND FLOW OF 15-20 KT IS THROUGHOUT MUCH OF THE AREA WITH SOME STRONGER WINDS TO 25 KT NEAR THE COAST OF COLOMBIA. THE WAVE OVER THE EASTERN CARIBBEAN IS EXPECTED TO CONTINUE MOVING WEST WITH LITTLE CHANGE ELSEWHERE. HISPANIOLA... HISPANIOLA IS CLEAR AND DRY AT THIS TIME. DRY AIR ALOFT COVERS THE AREA AND WILL CONTINUE TO PROVIDE FAIR CONDITIONS EXCEPT DURING PEAK DAYTIME HEATING IN THE AFTERNOON WHEN CONVECTION IS POSSIBLE. MOISTURE ASSOCIATED WITH A TROPICAL WAVE TO THE EAST WILL REACH THE ISLAND WITHIN THE NEXT 24 HOURS. ATLANTIC OCEAN... BROAD SURFACE RIDGING DOMINATES THE WEST ATLC AROUND A 1027 MB HIGH NEAR 34N73W. THE RIDGE IS SUPPORTED BY BROAD UPPER RIDGING CENTERED NEAR 35N69W. HOWEVER...A NARROW UPPER TROUGH ALONG 80W IS SUPPORTING ISOLATED SHOWERS/THUNDERSTORMS NEAR THE STRAITS OF FLORIDA. AN UPPER LEVEL LOW IS CENTERED NEAR 23N65W SUPPORTING A FEW ISOLATED SHOWERS FROM 21N-25N BETWEEN 63W-69W. A TROPICAL WAVE IS TO THE EAST SUPPORTING A FEW ISOLATED SHOWERS FROM 17N- 23N BETWEEN 56W-63W. AN AREA OF ENHANCED MOISTURE IS ALSO FARTHER EAST WHERE A FEW ISOLATED SHOWERS ARE FROM 14N-18N BETWEEN 46W-56W. A STATIONARY FRONT TO THE NORTH EXTENDS INTO THE AREA ALONG 30N BETWEEN 45W-60W SUPPORTING SCATTERED SHOWERS WITHIN 45 NM EITHER SIDE. THE REMAINDER OF THE BASIN IS DOMINATED BY BROAD SURFACE RIDGING. BROAD UPPER RIDGING COVERS THE TROPICAL ATLC CENTERED NEAR 14N55W. AN UPPER TROUGH IS TO THE NORTH SUPPORTING THE FRONTAL BOUNDARY. VERY DRY AIR IS THROUGHOUT THE EAST ATLC DUE TO THE PRESENCE OF A BROAD SAHARAN AIR LAYER. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ WALTON