000 AXNT20 KNHC 171805 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT TUE JUN 17 2014 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 1745 UTC. ...TROPICAL WAVES... A NE TO SE TILTED TROPICAL WAVE EXTENDS FROM 02N47W TO 07N46W TO 13N43W MOVING W AT 15-20 KT. VISIBLE SATELLITE IMAGERY SINCE 24 HRS AGO SHOW A SIGNIFICANT INCREASE IN DEEP LAYER MOISTURE ALONG AND WITHIN 150 NM EITHER SIDE OF THE WAVE AXIS. IN ADDITION... TOTAL PRECIPITABLE WATER IMAGERY INDICATES MAXIMUM VALUES IN THE VICINITY OF THE WAVE AXIS FROM 05N-14N BETWEEN 39W-48W. SCATTERED MODERATE CONVECTION IS SEEN FROM 07N TO 10N WITHIN 120 NM W OF THE WAVE...WHILE WIDELY SCATTERED MODERATE CONVECTION IS S OF 05N WITHIN 180 NM EITHER SIDE OF THE AXIS. THE 600-700 MB MODEL GUIDANCE ALONG SATELLITE DERIVED WINDS INFER THAT BROAD 700 MB TROUGHING IS PRESENT TO THE W OF THE WAVE FROM 10N TO NEAR 20N BETWEEN 50W AND 59W. THE 1214 UTC ASCAT PASS FROM THIS MORNING REVEALED A SHARP WIND SHIFT ACROSS THE WAVE AXIS FROM NE AT 15-20 KT TO THE N OF 07N...TO SE TO S TO THE S OF 07N. TROPICAL WAVE IS ALONG 77W S OF 17N MOVING W AT 10-15 KT. THE WAVE CONTINUES MOVING ACROSS THE CENTRAL CARIBBEAN AND WITH MOST ENERGY ALOFT REMAINING S OF 15N. THIS WAVE HEPLED PRODUCE 1.36 INCHES OF RAIN AT MONTEGO BAY JAMAICA DURING THE PAST 24 HRS. A RELATIVELY FAIR AMOUNT OF LOW-LEVEL ENERGY CONTINUES BETWEEN THIS WAVE AND ANOTHER WAVE THAT HAS MOVED JUST TO THE W OF CENTRAL AMERICA GENERATING AN OVERALL BROAD CYCLONIC ENVIRONMENT FOR THE WAVE TO MOVE THROUGH. ONLY ISOLATED SHOWERS AND TSTMS ARE NOTED WITHIN 180 NM OF THE WAVE. THE NORTHERN PORTION OF THE WAVE JUST W OF CENTRAL AMERICA EXTENDS NORTHWARD TO SE HONDURAS. NO CONVECTION IS OCCURRING WITH THIS WAVE. ...ITCZ/THE MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE COAST OF GUINEA-BISSAU NEAR AFRICAN COAST NEAR 12N16W TO 05N19W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 05N19W TO 04N25W TO 06N40W. 01N50W. ASIDE FROM CONVECTION ASSOCIATED WITH THE TROPICAL WAVE IN THE CENTRAL ATLC AS DESCRIBED ABOVE...SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS OCCURRING WITHIN 180 NM NW OF THE MONSOON TROUGH BETWEEN 18W-21. ISOLATED MODERATE CONVECTION IS ALONG AND WITHIN 60 NM OF THE ITCZ BETWEEN 24W-38W. ...DISCUSSION... GULF OF MEXICO... NORTHERLY UPPER LEVEL FLOW BETWEEN A LARGE UPPER LEVEL ANTICYCLONE SITUATED OVER CENTRAL MEXICO WITH AXIS ROUGHLY ALONG 98W AND UPPER TROUGHING OVER THE SW N ATLC DOMINATES THE GULF BASIN. THE OVERALL STABLE ENVIRONMENT CONTINUES TO SUPPORT A SURFACE RIDGE ACROSS THE NORTHERN GULF ANCHORED BY AN SPORADIC 1021-1022 MB HIGH PRES CENTER JUST S OF THE WESTERN FLORIDA PANHANDLE NEAR 30N88W. THE RIDGE IS PROMOTING MOSTLY FAIR SKIES AND FAIR CONDITIONS WITH PRIMARILY E-SE WINDS IN THE RANGE OF 10- 15 KT. THESE CONDITIONS ARE EXPECTED TO CONTINUE THROUGH THU AS THE RIDGE REMAINS STATIONARY. THE ONLY CONVECTION NOTED ON SATELLITE AND RADAR IMAGERY IS OF THE SCATTERED MODERATE/ISOLATED STRONG TYPE INTENSITY CAUSING REDUCED VISIBILITIES OVER THE FAR SE PART OF THE GULF NEAR...AND TO OVER THE FLORIDA KEYS AND COVERING PORTIONS OF S FLORIDA. THIS ACTIVITY MAY DECREASE IN COVERAGE THROUGH THE REST OF DAY...BUT SHOULD DEVELOP AGAIN IN THE EVENING HOURS INTO WED AS INSTABILITY ALOFT ASSOCIATED WITH THE UPPER TROUGH STAYS IN PLACE. CARIBBEAN SEA... WATER VAPOR IMAGERY INDICATES AN UPPER LEVEL TROUGH OVER THE NW CARIBBEAN WITH MOSTLY DRY AIR AND SUBSIDENCE PROMOTING FAIR WEATHER AT THE SURFACE N OF 16N W OF 79W. TO THE SE OF THE UPPER LEVEL TROUGH...SOUTHWESTERLY FLOW QUICKLY BECOMES GENERALLY WESTERLY FLOW OVER THE CENTRAL AND EASTERN CARIBBEAN WITH PLENTY OF MOSTLY MID/UPPER LEVEL CLOUDINESS AND MOISTURE. SCATTERED SHOWERS AND ISOLATED TSTMS EARLIER NOTED OVER JAMAICA AND EASTERN CUBA HAVE JUST ABOUT DISSIPATED DURING THE MORNING HRS AS DRIER AIR IN THE WAKE OF THE UPPER TROUGH HAS SEEPED EASTWARD TO NEAR 78W. SCATTERED SHOWERS AND TSTMS SHOULD DEVELOP OVER EASTERN CUBA...AND ALSO OVER THE WATERS BETWEEN EASTERN CUBA AND JAMAICA MOST PROBABLY LATER IN THE AFTERNOON...AND SHOULD CONTINUE INTO THE NIGHT TIME HRS FOR THE MOST PART. A VERY ACTIVE AREA OF SCATTERED TO NUMEROUS TSTMS IS SITUATED OVER THE SW CARIBBEAN S OF 16N W OF 80W TO JUST INLAND THE COAST OF CENTRAL AMERICA. THIS ACTIVITY HAS BEEN ACTIVE OVER THE PAST 3-4 DAYS AS IT REMAINS UNDER FAVORABLE UPPER LEVEL CONDITIONS FOUND TO THE S OF THE AFOREMENTIONED UPPER TROUGH WHERE UPPER LEVEL DIFFLUENT FLOW IS OBSERVED. THIS CONVECTIVE ACTIVITY IS FORECAST TO CHANGE LITTLE OVER THE NEXT 48 HRS WITH STILL A POSSIBILITY OF WEAK LOW PRES DEVELOPING IN THAT AREA. OTHERWISE ...TRADES REMAIN IN THE RANGE OF 15-20 KT EXCEPT FOR 25-30 KT WINDS S OF 13N BETWEEN 75W-77W. ...HISPANIOLA... CURRENTLY MOISTURE CONTINUES TO BE ADVECTED OVER THE ISLAND FROM THE WEST AS AN UPPER LEVEL TROUGH AXIS EXTENDS FROM AN UPPER LOW OVER THE SW NORTH ATLC NEAR 29N76W SW TO ACROSS CENTRAL CUBA... AND TO A BASE OVER THE GULF OF HONDURAS NEAR 16N88W. LOW-LEVEL MOISTURE CONVERGENCE DUE TO THE PRESENCE OF A TROPICAL WAVE TO THE S ALONG 77W IN COMBINATION WITH DIFFLUENT ALOFT TO THE W OF THE UPPER LEVEL TROUGH IS PRODUCING MOISTURE IN THE FORM OF BROKEN LOW CLOUDS...AND BROKEN MID/UPPER CLOUDS TO THE N OF 16N BETWEEN 70W AND 75W. SCATTERED SHOWERS AND ISOLATED TSTMS ARE OCCURRING WITH THESE CLOUDS. MODEL GUIDANCE SUGGESTS THAT THE UPPER TROUGH WILL REMAIN TO THE W OF THE ISLAND DURING THE NEXT 24 TO 48 HOURS ALLOWING FOR SIMILAR SHOWER/TSTM ACTIVITY TO CONTINUE AS MENTIONED ABOVE. ATLANTIC OCEAN... WATER VAPOR IMAGERY SHOWS AN UPPER LEVEL LOW CENTERED NEAR 29N77W WITH A TROUGH EXTENDING FROM THE LOW SW TO S FLORIDA. THIS FEATURE SUPPORTS A WEAK TROUGH FROM THE NORTHERN BAHAMAS NNE TO NEAR 30N76W. SCATTERED TSTMS ARE OBSERVED IN RADAR AND SATELLITE IMAGERY TO BE CONFINED OVER THE BAHAMAS...AND WATERS S OF 27N W OF 76W TO PARTS OF S FLORIDA. SCATTERED SHOWERS AND ISOLATED ARE OCCURRING WITHIN 180 NM OF THE TROUGH. A WEAKENING COLD FRONT EXTENDS FROM 32N57W SW TO 28N66W TO 28N71W WHERE IT BEGINS TO DISSIPATE AS IT EXTENDS TOWARDS HIGH PRES REACHING TO NEAR 29N75W. A PRE-FRONTAL TROUGH EXTENDS FROM 31N59W TO 28N63W TO 27N67W. A NEW UPPER LEVEL LOW MOVING S IS SEEN NEAR 29N65W WITH A SHEAR AXIS EXTENDING TO 28N68W. INSTABILITY ALOFT ASSOCIATED WITH THE LOW IN COMBINATION WITH THE FRONT IS RESULTING IN SCATTERED TSTM ACTIVITY WITHIN 150 NM SE OF THE FRONT TO INCLUDE THE AREA BETWEEN THE FRONT AND TROUGH. A TROUGH EXTENDS FROM 27N54W TO 22N62W. ISOLATED SHOWERS AND TSTMS ARE WITHIN 120 NM OF THE TROUGH. ELSEWHERE...HIGH PRES IS PRESENT TO N OF 20N AND E OF THIS TROUGH...AND ALSO N OF 26N W OF 67W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ AGUIRRE