000 AXNT20 KNHC 221045 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT THU AUG 22 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 EXTENDS FROM 10N45W TO 18N42W MOVING W AT 15 KT. THE WAVE REMAINS EMBEDDED WITHIN THE MONSOON TROUGH AT THE SURFACE AND WITHIN A LOWER AMPLITUDE 700 MB TROUGH BETWEEN 40W- 50W. TO THE EAST OF THIS AREA...GLOBAL MODEL GUIDANCE INDICATES ANOTHER HIGHER AMPLITUDE IMPULSE OF 700 MB TROUGHING IS LOCATED BETWEEN 30W-40W. AT THIS TIME ANY SIGNIFICANT CONVECTION REMAINS CONFINED SOUTH OF THE MONSOON TROUGH AXIS. TROPICAL WAVE EXTENDS FROM 12N81W TO 22N80W MOVING W AT 10-15 KT. THE WAVE REMAINS WITHIN BROAD LOW-LEVEL...SURFACE TO 700 MB...TROUGHING LOCATED ACROSS THE WESTERN CARIBBEAN SEA WITH TOTAL PRECIPITABLE WATER IMAGERY INDICATING MAXIMUM VALUES GENERALLY BETWEEN 73W-83W. WIDELY SCATTERED MODERATE CONVECTION IS FROM 13N-22N BETWEEN 76W-83W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM 12N17W TO 16N27W TO 10N45W TO 07N51W. ISOLATED MODERATE CONVECTION IS FROM 08N-14N BETWEEN 15W- 28W...FROM 08N-11N BETWEEN 36W-40W...AND FROM 06N-10N BETWEEN 46W-54W. ...DISCUSSION... GULF OF MEXICO... UPPER LEVEL DIFFLUENT FLOW IS NOTED ON WATER VAPOR IMAGERY OCCURRING BETWEEN AN UPPER LEVEL LOW CENTERED OVER NORTHERN MEXICO NEAR 27N103W AND AN UPPER LEVEL ANTICYCLONE CENTERED OVER THE EAST PACIFIC REGION NEAR 16N100W. MIDDLE TO UPPER LEVEL DIFFLUENCE IS GENERATING ISOLATED SHOWERS OVER THE WESTERN GULF THIS MORNING WEST OF A LINE FROM 29N95W TO 19N93W. FARTHER EAST...AN UPPER LEVEL LOW IS CENTERED OVER WESTERN CUBA NEAR 22N82W. THIS UPPER LEVEL FEATURE ALONG WITH A MID-LEVEL VORTICITY MAXIMUM OVER THE NE GULF NEAR 26N87W IS GENERATING SCATTERED SHOWERS AND WIDELY SCATTERED TSTMS N OF 23N E OF 91W...INCLUDING PORTIONS OF THE FLORIDA PENINSULA AND FLORIDA STRAITS. MOST OF THIS CONVECTIVE ACTIVITY IS FOCUSED IMMEDIATELY OFFSHORE OF THE FLORIDA PENINSULA FROM 23N-29N BETWEEN 81W-86W. LOOKING AHEAD...GENERALLY E-SE WINDS ARE EXPECTED TO PREVAIL THROUGH THE UPCOMING WEEKEND AND REMAIN 20 KT OR LESS AS A SURFACE RIDGE CONTINUES TO BE ANCHORED OVER THE SW NORTH ATLC WITH A RIDGE AXIS EXTENDING WESTWARD ALONG 30N. CARIBBEAN SEA... AN UPPER LEVEL LOW IS CENTERED OVER WESTERN CUBA NEAR 22N82W AND ALONG WITH A TROPICAL WAVE ALONG 81W CONTINUES TO GENERATE SCATTERED SHOWERS AND TSTMS IN THE ADJACENT OFFSHORE WATERS OF CUBA...THE CAYMAN ISLANDS...AND JAMAICA. THIS CONVECTION STRETCHES SOUTHWARD IN THE VICINITY OF THE TROPICAL WAVE AXIS FROM 13N-21N BETWEEN 76W-83W. THE WAVE IS EXPECTED TO CONTINUE A WESTWARD MOVEMENT OVER THE NEXT 24 TO 48 HOURS BRINGING INCREASED PRECIPITATION CHANCES TO CENTRAL AMERICA AND THE NW CARIBBEAN WATERS. TO THE SOUTH...THE MONSOON TROUGH IS ALONG 09N/10N EXTENDING FROM NORTHERN COLOMBIA WESTWARD INTO THE EAST PACIFIC REGION. ISOLATED SHOWERS AND TSTMS ARE OCCURRING WITHIN 120 NM EITHER SIDE OF THE AXIS...INCLUDING PORTIONS OF PANANA AND COSTA RICA THIS MORNING. FINALLY...E-SE TRADES CONTINUE ACROSS THE EASTERN CARIBBEAN WITH ABUNDANT LOW-LEVEL MOISTURE AS NOTED ON TOTAL PRECIPITABLE WATER IMAGERY. WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING E OF 71W AND ARE PRIMARILY FOCUSED IN THE VICINITY OF 16N66W. HISPANIOLA... EARLIER OVERNIGHT CONVECTION HAS DIMINISHED WITH ONLY A FEW ISOLATED SHOWERS POSSIBLE THIS MORNING. NORTH-NORTHWESTERLY FLOW ALOFT REMAINS OVER THE ISLAND BETWEEN AN UPPER LEVEL TROUGH TO THE NE OVER THE ATLC...AND UPPER LEVEL RIDGING TO THE WEST. PARTIAL DRYING ALOFT IS EXPECTED OVER THE NEXT 12 TO 24 HOURS... HOWEVER LOW-LEVEL MOISTURE WILL CONTINUE TO ADVECT WESTWARD WITHIN THE E-SE TRADES ACROSS THE EASTERN AND CENTRAL CARIBBEAN. THE LOW-LEVEL MOISTURE ALONG WITH PEAK DAYTIME HEATING AND INSTABILITY WILL INITIATE AFTERNOON SHOWERS AND TSTMS. ANY ACTIVITY THAT FORMS WILL LIKELY LAST INTO THE EVENING HOURS AND DIMINISH THEREAFTER. ATLANTIC OCEAN... AN UPPER LEVEL LOW IS CENTERED OVER WESTERN CUBA NEAR 22N82W THAT CONTINUES TO PRODUCE ENHANCEMENT FOR WIDELY SCATTERED SHOWERS AND ISOLATED TSTMS OCCURRING W OF 75W ACROSS PORTIONS OF THE SW NORTH ATLC. THIS ACTIVITY REMAINS ON THE SOUTHWESTERN PERIPHERY OF A SURFACE RIDGE ANCHORED BY A 1021 MB HIGH CENTERED OFF THE CAROLINA COAST NEAR 32N74W. THE SURFACE HIGH IS LARGELY SUPPORTED BY A MIDDLE TO UPPER LEVEL ANTICYCLONE CENTERED NEAR 29N71W. FARTHER EAST...AN UPPER LEVEL TROUGH AXIS EXTENDS FROM 32N53W SW TO A BASE NEAR 17N67W. MOISTURE ASSOCIATED WITH A STATIONARY FRONT ANALYZED FROM 32N55W TO 29N60W TO 29N65W CONTINUES TO PRODUCE WIDELY SCATTERED SHOWERS WITHIN 90 NM EITHER SIDE OF THE BOUNDARY. OTHERWISE...THE REMAINDER OF THE CENTRAL AND EASTERN ATLC IS UNDER THE INFLUENCE OF A SURFACE RIDGE ANCHORED BY A 1022 MB HIGH CENTERED SOUTH OF THE AZORES NEAR 34N27W. THE RIDGE AXIS EXTENDS SOUTHWEST FROM THE HIGH TO NEAR 29N48W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN