000 AXNT20 KNHC 111043 TWDAT TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 805 AM EDT SUN OCT 11 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1015 UTC. ...TROPICAL WAVES... TROPICAL WAVE EXTENDS FROM 10N40W TO 18N34W MOVING W AT 10-15 KT. THE WAVE COINCIDES WITH BROAD 700 MB TROUGHING BETWEEN 32W- 43W AND TOTAL PRECIPITABLE WATER IMAGERY INDICATING A MOISTURE MAXIMUM STRETCHING FROM 17N34W SW TO 11N41W. ISOLATED MODERATE CONVECTION IS OCCURRING WITHIN 180 NM EITHER SIDE OF THE AXIS. TROPICAL WAVE EXTENDS FROM 10N80W TO 19N78W MOVING W AT 10 KT. THE WAVE COINCIDES WITH BROAD 700 MB TROUGHING BETWEEN 76W-83W WITH A MAXIMUM IN 850 MB RELATIVE VORTICITY AT THE SOUTHERN EXTENT OF THE AXIS. MOVING BENEATH UPPER LEVEL TROUGHING EXTENDING S-SW FROM OVER HISPANIOLA TO NEAR 12N79W...ISOLATED MODERATE TO STRONG CONVECTION IS FROM 10N-14N BETWEEN 76W-84W. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH AXIS EXTENDS FROM THE AFRICAN COAST NEAR 12N17W TO 08N23W TO 08N32W. THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 11N42W TO 07N58W. OUTSIDE OF CONVECTION ASSOCIATED WITH THE TROPICAL WAVE ALONG 37W...SCATTERED MODERATE CONVECTION IS FROM 05N-13N BETWEEN 09W-15W...FROM 04N-12N BETWEEN 19W-30W...AND FROM 08N-13N BETWEEN 40W-50W. ...DISCUSSION... GULF OF MEXICO... NORTHWESTERLY FLOW ALOFT INFLUENCES MUCH OF THE GULF BASIN THIS MORNING BETWEEN UPPER LEVEL RIDGING OVER MOST OF MEXICO AND A MIDDLE TO UPPER LEVEL SHORTWAVE TROUGH FOCUSED AROUND AN UPPER LEVEL LOW OVER THE CAROLINAS WITH TROUGHING EXTENDING W-SW TO OVER COASTAL SE TEXAS. THIS SHORTWAVE SUPPORTS A COMPLEX AREA OF LOW PRESSURE OFFSHORE OF SOUTH CAROLINA WITH A WEAK COLD FRONT EXTENDING ACROSS THE SOUTHERN FLORIDA PENINSULA AND A WEAK STATIONARY FRONT EXTENDING FROM NEAR 26N82W TO 24N90W TO 23N97W. WHILE THE UPPER LEVELS REMAIN RELATIVELY DRY AND STABLE...THE COLD FRONT AT THE SURFACE REMAINS DRY AS WELL WITH ONLY A FEW ISOLATED SHOWERS OCCURRING ACROSS THE WEST-CENTRAL WATERS IN THE VICINITY OF 23N97W. OTHERWISE...THE FRONT IS EXPECTED TO BECOME DIFFUSE SUNDAY AS ANOTHER WEAK IMPULSE OF ENERGY ROTATES SOUTHWARD ACROSS THE EASTERN GULF AND FLORIDA PENINSULA USHERING IN A MILDER AIRMASS THROUGH MONDAY. WINDS ARE EXPECTED TO REMAIN NORTHERLY IN THE RANGE OF GENTLE TO MODERATE BREEZES AS HIGH PRESSURE SETTLES IN ACROSS THE WESTERN GULF LATE SUNDAY INTO MONDAY. CARIBBEAN SEA... NORTH-NORTHEASTERLY WINDS ALOFT ARE PROVIDING A STABLE AND RELATIVELY DRY ENVIRONMENT OVER MUCH OF THE NW CARIBBEAN BETWEEN RIDGING OVER MEXICO AND THE WESTERN EXTENT OF AN UPPER LEVEL TROUGH CENTERED OVER THE CENTRAL CARIBBEAN. WHILE CONDITIONS ACROSS THE NW CARIBBEAN REMAIN TRANQUIL THIS MORNING...THE PRESENCE OF A TROPICAL WAVE ALONG 80W IS PROVIDING FOCUS FOR WIDELY SCATTERED SHOWERS AND TSTMS GENERALLY S OF 15N BETWEEN 75W-84W. SOME OF THIS ACTIVITY IS LIKELY ENHANCED DUE TO THE CLOSE PROXIMITY OF THE MONSOON TROUGH AXIS EXTENDING FROM NORTHERN COLOMBIA NEAR 10N76W TO COSTA RICA. FARTHER EAST... WITHIN SOUTHWESTERLY FLOW ALOFT ON THE EASTERN PERIPHERY OF THE UPPER LEVEL TROUGH AXIS EXTENDING FROM HISPANIOLA SW TO 12N79W...ISOLATED SHOWERS AND TSTMS ARE OCCURRING WITHIN 90 NM EITHER SIDE OF A LINE FROM 17N76W TO 15N67W TO 10N59W. THE STRONGEST ACTIVITY IS NOTED ACROSS THE WINDWARD ISLANDS WITHIN AN AREA OF MAXIMUM MIDDLE TO UPPER LEVEL DIFFLUENCE. OTHERWISE...MODERATE TO FRESH TRADES PERSIST ACROSS THE BASIN WITH THE STRONGEST WINDS NOTED S OF 15N BETWEEN 66W-75W. ...HISPANIOLA... CURRENTLY AN UPPER LEVEL TROUGH CENTERED OVER THE ISLAND IS PROVIDING FOR INCREASED MOISTURE AND CLOUDINESS ACROSS THE REGION. WHILE MOSTLY CLEAR SKIES PREVAIL THIS MORNING...AS THE UPPER LEVEL LOW WEAKENS BY MONDAY...CONDITIONS ARE EXPECTED TO IMPROVE INTO EARLY NEXT WEEK. ATLANTIC OCEAN... A MIDDLE TO UPPER LEVEL SHORTWAVE LOW IS CENTERED OVER THE CAROLINAS WITH TROUGH AXIS EXTENDING W-SW OVER THE NORTHERN GULF OF MEXICO COAST. HOWEVER TROUGHING DOES DIP SOUTHWARD OVER MUCH OF THE SW NORTH ATLC REGION AS WELL N OF 26N W OF 70W. THE UPPER LEVEL DYNAMICS SUPPORT A COMPLEX AREA OF LOW PRESSURE FOCUSED ON A 1006 MB LOW CENTERED NEAR 32N76W WITH A WEAK COLD FRONT EXTENDING TO THE FLORIDA PENINSULA NEAR 27N80W. A WARM FRONT ALSO EXTENDS FROM THE 1016 MB TO THE E-SE TO NEAR 29N70W SUPPORTING SCATTERED SHOWERS AND TSTMS GENERALLY N OF 26N BETWEEN 66W-78W. THE LOW IS EXPECTED TO DRIFT NORTHEASTWARD DURING THE NEXT 24 HOURS WITH THE AREA OF CONVECTION EXPECTED TO SHIFT SLIGHTLY E-NE. OTHERWISE...THE REMAINDER OF THE CENTRAL AND EASTERN ATLC IS UNDER THE INFLUENCE OF A RATHER EXPANSIVE RIDGE ANCHORED BY A 1018 MB HIGH CENTERED NEAR 27N53W AND A 1019 MB HIGH CENTERED NEAR 27N53W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ HUFFMAN