000 AXNT20 KNHC 101715 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 205 PM EDT FRI JUL 10 2015 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1615 UTC. ...TROPICAL WAVES... A TROPICAL WAVE IS OVER THE E ATLANTIC WITH AXIS APPROXIMATELY ALONG 35W...MOVING W AT 10 TO 15 KT. TOTAL PRECIPITABLE WATER AND METEOSAT IMAGERY DEPICT THIS LARGE WAVE AT THE BOUNDARY BETWEEN A DRY AND DUSTY SAHARAN AIR LAYER TO THE WEST AND A SURGE OF QUITE MOIST CONDITIONS TO THE EAST. NO SIGNIFICANT CONVECTION IS ASSOCIATED WITH THE WAVE AT THIS TIME. A TROPICAL WAVE IS APPROACHING THE LESSER ANTILLES WITH AXIS APPROXIMATELY ALONG 60W...MOVING W AT AROUND 15 KT. TOTAL PRECIPITABLE WATER IMAGERY INDICATE ONLY A SLIGHT MAXIMUM IN MOISTURE ON THE EASTERN SIDE OF THE WAVE AXIS WITH SUBSTANTIAL DRY AND DUSTY AIR NORTH OF 13N. RAWINDSONDES IN THE LESSER ANTILLES ARE ALSO USEFUL IN IDENTIFYING THE LOCATION OF THIS WAVE. IT HAS NO SIGNIFICANT CONVECTION ASSOCIATED AT THIS TIME. A TROPICAL WAVE IS OVER THE WESTERN CARIBBEAN WITH AXIS EXTENDING FROM 20N87W...ACROSS HONDURAS...AND INTO THE NORTHEAST PACIFIC OCEAN...MOVING W AT 15 KT. THE WAVE IS BECOMING INDISTINCT IN TPW...RAWINDSONDES...AND MODEL ANALYSES AS IT BEGINS TO INTERACT WITH THE LARGE MONSOONAL LOW IN THE NORTHEAST PACIFIC SOUTH OF MEXICO. SCATTERED MODERATE CONVECTION EXISTS FROM 10-13N BETWEEN 82-85W NEAR NICARAGUA. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM THE AFRICAN COAST NEAR 16N16W TO 07N33W. THE ITCZ BEGINS NEAR 08N37W AND CONTINUES TO 10N57W. SCATTERED MODERATE CONVECTION IS NORTH OF 03N TO THE WEST AFRICAN COAST EAST OF 00W. ISOLATED SHOWERS ARE FROM 05N TO 10N BETWEEN 10W AND 20W. ...DISCUSSION... GULF OF MEXICO... A SURFACE RIDGE EXTENDS WESTWARD JUST INLAND OF THE NORTHERN GULF OF MEXICO. A MODERATE PRESSURE GRADIENT ACROSS THE GULF IS PRODUCING GENERALLY WEAK EAST TO SOUTHWEST WINDS. A SURFACE TROUGHS IS ANALYZED IN THE SOUTHWESTERN GULF...THOUGH NO SIGNIFICANT WEATHER IS ASSOCIATED WITH IT. DURING THE NEXT TWO DAYS...THE SURFACE RIDGE WILL SLIDE SOUTHWESTWARD TO THE NORTHERN GULF AND WINDS WILL STAY WEAK BUT HAVE A NORTHERLY COMPONENT. CONVECTION LIKELY TO STAY MINIMAL OVER THE GULF DURING THE NEXT COUPLE OF DAYS. CARIBBEAN SEA... A VERY VIGOROUS TROPICAL UPPER TROPOSPHERIC TROUGH...OR TUTT...IS LOCATED OVER THE SOUTHERN BAHAMAS. VERY STRONG WEST- NORTHWESTERLIES ALOFT ACROSS THE CARIBBEAN ALONG WITH 20-30 KT TRADEWINDS NEAR THE SURFACE ARE PRODUCING VERTICAL SHEAR ON THE ORDER OF 60-70 KT. THIS IS QUITE A BIT MORE THAN TYPICAL FOR JULY...MAKING TROPICAL CYCLONE FORMATION IN THE LOW LATITUDES EXTREMELY UNLIKELY. ASIDE FROM THE MODERATE CONVECTION ASSOCIATED WITH THE WAVE OVER CENTRAL AMERICA...NO OTHER SIGNIFICANT CONVECTION IS OBSERVED OVER THE CARIBBEAN. THE SURFACE WINDS SHOULD CONTINUE TO BE STRONG...THOUGH THE CHANCES FOR DEEP CONVECTION MAY GO UP AS THE TROPICAL WAVE PROGRESSES WESTWARD TO THE EASTERN CARIBBEAN ON SATURDAY AND THE CENTRAL CARIBBEAN ON SUNDAY. ...HISPANIOLA... VERY DRY AIR IS PRESENTLY ACROSS THE ISLAND AS DEPICTED BY TOTAL PRECIPITABLE WATER IMAGERY. THIS IS SUPPORTING CLEAR SKIES AND FAIR WEATHER AT THE TIME. LITTLE CHANGE IS EXPECTED DURING THE NEXT COUPLE OF DAYS. ATLANTIC OCEAN... THE STRONG TUTT OVER THE CENTRAL BAHAMAS IS CONNECTED TO ANOTHER UPPER LOW NEAR 25N55W OVER THE CENTRAL ATLANTIC. THESE TWO SYSTEMS ARE FORCING SUBSTANTIAL UPPER LEVEL WESTERLIES AND THUS STRONG VERTICAL SHEAR ACROSS MOST OF THE SUBTROPICAL ATLANTIC WEST OF 40W. AT THE SURFACE...A 1022 MB HIGH IS CENTERED AT 29N75W. A TROUGH EXTENDS FROM 31N56W SOUTHWESTWARD TO 28N59W...ASSOCIATED WITH SCATTERED SHOWERS WITHIN 30 NM OF THE TROUGH AXIS. FARTHER EAST...A SURFACE HIGH IS CENTERED AT 36N25W WITH A RIDGE AXIS EXTENDING TOWARD THE WEST-SOUTHWEST. EQUATORWARD OF THE HIGH AND RIDGE...THE EASTERLY TRADEWINDS ARE GENERALLY 10-20 KT. NO SIGNIFICANT DEEP CONVECTION IS OCCURRING EXCEPT THAT MENTIONED NEAR WEST AFRICA ASSOCIATED WITH THE MONSOON TROUGH. NO SUBSTANTIAL CHANGES TO THE SURFACE WINDS ARE ANTICIPATED...THOUGH THE TROPICAL WAVE CURRENTLY AT 35W MAY PRODUCE SOME DEEP CONVECTION DURING THE NEXT COUPLE OF DAYS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ LANDSEA