000 AXPZ20 KNHC 022121 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC SAT NOV 02 2013 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2100 UTC. ...SPECIAL FEATURES... TROPICAL DEPRESSION EIGHTEEN-E CENTERED NEAR 17.7N 109.8W AT 02/2100 UTC OR 313 NM S OF THE SOUTHERN TIP OF BAJA CALIFORNIA MOVING WNW AT 5 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1006 MB. MAXIMUM SUSTAINED WIND SPEED IS 30 KT WITH GUSTS TO 40 KT. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP3/WTPZ23 KNHC FOR MORE DETAILS. THE DEPRESSION REMAINS SHEARED WITH THE CONVECTION CONFINED TO THE NW HALF OF THE SYSTEM. NUMEROUS MODERATE AND SCATTERED STRONG CONVECTION IS WITHIN 180 NM W OF A LINE FROM 21N109W TO 17N109W TO 15N112W. THE OFFICIAL FORECAST STILL CALLS FOR SOME SLIGHT STRENGTHENING TO MINIMAL TROPICAL STORM STATUS DURING THE NEXT 24 HOURS AS IT CONTINUES TO THE N...THEN WILL LIKELY WEAKEN AS IT APPROACHES LAND DUE TO INCREASING SHEAR. BUILDING SURF WILL IMPACT THE SOUTHERN BAJA CALIFORNIA PENINSULA...SPREADING INTO THE SOUTHERN GULF OF CALIFORNIA AND IMPACTING THE W CENTRAL MEXICAN COAST LATER THIS WEEKEND INTO EARLY NEXT WEEK UNTIL DISSIPATION OCCURS ONCE THE DEPRESSION MOVES INLAND. THE NEXT GAP WIND EVENT FOR THE GULF OF TEHUANTEPEC IS FORECAST TO INITIATE TONIGHT INTO EARLY SUN MORNING. A STRONG COLD FRONT IS MOVING INTO THE SW GULF OF MEXICO REGION. NORTHERLY WINDS WILL FUNNEL THROUGH THE CHIVELA PASS AND DOWNWIND THROUGH THE GULF OF TEHUANTEPEC. MODEL GUIDANCE INDICATES WINDS RAPIDLY INCREASING TO GALE FORCE WITH THE GFS AND NAM SHOWING WINDS TO 40 KT DURING THE EARLY MORNING HOURS ON SUN. RESULTANT SEAS WILL LIKELY BUILD TO UP TO AT LEAST 15 FT. CONDITIONS WILL THEN IMPROVE WITH WINDS DIMINISHING LATE SUN THROUGH MON. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM 09N78W TO 10N90W...THEN RESUMES FROM LOW PRES NEAR 15.5N122W TO 11N128W. THE ITCZ AXIS EXTENDS FROM 11N128W TO BEYOND 09N140W. SCATTERED MODERATE CONVECTION IS WITHIN 75 NM EITHER SIDE OF THE ITCZ W OF 134W. ADDITIONALLY...SCATTERED MODERATE CONVECTION IS WITHIN 90 NM S OF A LINE FROM 06N92W TO 07N98W...AND ALSO FROM 07N TO 09N BETWEEN 124W AND 127W. ...DISCUSSION... A BROAD UPPER LEVEL ANTICYCLONE IS CENTERED OVER WEST-CENTRAL MEXICO NEAR 20N106W...EXTENDING A RIDGE AXIS E-SE TO THE YUCATAN PENINSULA...AND TO THE SW-W THROUGH 14N128W TO BEYOND 12N140W. STRONG DEEP LAYER NE-E WINDS ARE NOTED ON WATER VAPOR IMAGERY FROM OVER THE NW CARIBBEAN AND NORTHERN CENTRAL AMERICA INTO THE ADJACENT PACIFIC WATERS BETWEEN THE UPPER LEVEL ANTICYCLONE AND AN UPPER LEVEL LOW OFF THE NE COAST OF NICARAGUA. THE SUBSIDENT DRY AIR ASSOCIATED WITH THIS NE FLOW IS INHIBITING THE DEVELOPMENT OF CONVECTION WITH ONLY A FEW SMALL AREAS PRESENT AS IS DESCRIBED IN THE SECTION ABOVE. A WEAK SURFACE TROUGH IS ANALYZED FROM 07N TO 11N ALONG 92W AND CONTINUES TO PROVIDE CONVERGING SW WINDS IN THE RANGE OF 15 TO 20 KT INTO THE MONSOON TROUGH E OF 95W. WHILE THIS WAVE OF LOW- LEVEL ENERGY REMAINS AS AN OPEN TROUGH...THERE IS GOOD CONSENSUS AMONG GLOBAL MODELS THAT THE SURFACE TROUGH OR A WEAK LOW PRES AREA WILL LINGER OVER THE NEXT 2 TO 3 DAYS...BUT WILL GRADUALLY WEAKEN IN THE ABSENCE OF ABUNDANT DEEP LAYER MOISTURE OR STRONG SOUTHWESTERLY LOW-LEVEL CONVERGENCE. BROAD SURFACE RIDGING IS ACROSS THE NW DISCUSSION WATERS. THIS RIDGING...IN CONJUNCTION WITH BROAD LOW PRES ALONG THE MONSOON TROUGH...IS PRODUCING MODERATE TO FRESH BREEZE TRADEWINDS AND SEAS LESS THAN 8 FT. NO SIGNIFICANT COLD FRONTS ARE EXPECTED S OF 30N IN THE NEXT SEVERAL DAYS AND THE TRADEWINDS SHOULD REMAIN BELOW HIGH SEAS CRITERIA THROUGH THU. ALTHOUGH WINDS WILL REMAIN BELOW CRITERIA...A SET OF NW SWELL WITH HEIGHTS OF 8 FT OR GREATER WILL REACH ACROSS THE WATERS N OF 28N BETWEEN 123W AND 134W BY SUN AFTERNOON AS A COLD FRONT DOES MANAGE TO SKIRT BY N OF 30N. THESE SEAS WILL SLOWLY PROPAGATE TO THE SE-S FROM 24-48 HOURS WITH SEAS UP TO 12 FT NEAR 30N BY MON AFTERNOON. ALSO BY MON AFTERNOON..THE PRES GRADIENT IS FORECAST TO STRENGTHEN ACROSS THE FAR N CENTRAL WATERS WITH FRESH TO STRONG NORTHERLY WINDS LIKELY N OF 28N BETWEEN 120W AND 130W. $$ LEWITSKY