000 FZPN03 KNHC 020916 HSFEP2 TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0830 UTC. ...SPECIAL FEATURES... TROPICAL DEPRESSION EIGHTEEN-E CENTERED NEAR 17.2N 108.7W AT 02/0900 UTC OR 270 NM WSW OF MANZANILLO MEXICO MOVING WNW AT 4 KT. ESTIMATED MINIMUM CENTRAL PRESSURE REMAINS 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. ALL OF THE ASSOCIATED CONVECTION REMAINS ON THE NW HALF OF THE SYSTEM DUE TO STRONG WIND SHEAR WITH NUMEROUS MODERATE AND ISOLATED STRONG CONVECTION NOTED WITHIN 180 NM IN THE NW QUADRANT OF THE CENTER OF THE DEPRESSION. THE TROPICAL DEPRESSION IS FORECAST TO STRENGTHEN TO A MINIMAL TROPICAL STORM DURING THE NEXT 24 HOURS WHILE TURNING MORE TO W-NW AS A RIDGE BUILDS OVER MEXICO. IT IS THEN FORECAST TO MAKE A SHARP TURN TO THE NE TOWARD THE SOUTHERN BAJA CALIFORNIA PENINSULA AND W CENTRAL MEXICO DUE TO A LARGE UPPER LEVEL LOW W OF THE AREA. THE NEXT GAP WIND EVENT FOR THE GULF OF TEHUANTEPEC IS FORECAST FOR TONIGHT. A STRONG COLD FRONT WILL BE MOVING BY N OF THE AREA IN THE SW GULF OF MEXICO. NORTHERLY WINDS WILL FUNNEL THROUGH THE CHIVELA PASS BEHIND THE FRONT AND DOWNWIND THROUGH THE GULF OF TEHUANTEPEC. EARLIER MODEL GUIDANCE ALONG WITH THE LATEST MODEL GUIDANCE INDICATES WINDS RAPIDLY INCREASING TO GALE FORCE WITH THE GFS SHOWING WINDS TO 40 KT COMMENCING BY LATE TONIGHT AND CONTINUING INTO EARLY SUN. RESULTANT SEAS WILL LIKELY BUILD TO UP TO AT LEAST 15 FT. CONDITIONS WILL THEN IMPROVE WITH WINDS DIMINISHING LATE SUN. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM 10N85W TO LOW PRES NEAR 09N92W THEN RESUMES FROM LOW PRES NEAR 15N119W TO 09N125W TO 09N135W TO 08N140W. NO ITCZ IS PRESENT E OF 140W. SCATTERED MODERATE TO STRONG CONVECTION IS WITHIN 120 NM S OF THE AXIS BETWEEN 82W AND 86W OFF THE COAST OF COSTA RICA. SCATTERED MODERATE CONVECTION NOTED WITHIN 60 NM S OF AXIS BETWEEN 126W AND 128W...AND WITHIN 60 NM EITHER SIDE OF AXIS W OF 138W. ...DISCUSSION... A BROAD UPPER ANTICYCLONE IS CENTERED OVER CABO CORRIENTES IN W CENTRAL MEXICO NW OF MANZANILLO...EXTENDING E TO W FROM THE SW GULF TO 15N120W. THE E TO SE FLOW ON THE SOUTHERN EDGE OF THE UPPER RIDGE IS PROVIDING THE SHEAR OF THE TROPICAL DEPRESSION NEAR 17.2N 108.7W. FARTHER TO THE SE...STRONG DEEP LAYER NE WINDS ARE NOTED FROM THE NW CARIBBEAN AND ACROSS NORTHERN CENTRAL AMERICA INTO ADJACENT PACIFIC WATERS BETWEEN THE UPPER ANTICYCLONE AND AN UPPER CYCLONE OFF THE CARIBBEAN COAST OF NICARAGUA. THE SUBSIDENT DRY AIR ASSOCIATED WITH THIS NE FLOW IS INHIBITING THE DEVELOPMENT OF THE ROUTINE OVERNIGHT COASTAL CONVECTION FROM NICARAGUA TO SOUTHERN MEXICO. THERE ARE CLUSTERS OF CONVECTION OFF COSTA RICA HOWEVER...POSITIONED ALONG THE MONSOON TROUGH AND JUST OUTSIDE THE AREA OF DRYING NE FLOW. AN ASCAT PASS FROM 03 UTC INDICATED 15 TO 20 KT SW WINDS CONVERGING INTO THE MONSOON TROUGH E OF 95W...SUPPORTING THE CONVECTION AS WELL AS A WEAK 1009 MB SURFACE CENTERED NEAR 09N92W. THE GENESIS OF THIS LOW PRES MAY HAVE BEEN A TROPICAL WAVE THAT MIGRATED ACROSS THIS AREA OVER THE PAST COUPLE OF DAYS. THERE IS GOOD CONSENSUS AMONG GLOBAL MODELS THAT THIS LOW PRES WILL LINGER OVER THE NEXT 2 TO 3 DAYS...BUT GRADUALLY WEAKEN IN THE ABSENCE OF ABUNDANT DEEP LAYER MOISTURE OR STRONG SW LOW CONVERGENCE. THE WAVE FORECASTING FOR TROPICAL DEPRESSION EIGHTEEN-E CONTINUES TO BE BOOSTED SIGNIFICANTLY ABOVE ANY AVAILABLE GLOBAL MODEL AND GFDL BASED WAVEWATCH-III GUIDANCE. THIS IS BECAUSE THE WIND FORCING FROM THESE MODELS REMAINS TOO LOW COMPARED TO THE NHC OFFICIAL FORECAST. MAXIMUM WAVE HEIGHTS ARE EXPECTED TO BE JUST BELOW 15 FT...IF THE SYSTEM BECOMES A LOW-END TROPICAL STORM AS IS CURRENTLY PREDICTED. WINDS AND SEAS FROM THIS CYCLONE WILL DIMINISH AFTER LANDFALL IN MEXICO LATE ON MON OR EARLY ON TUE. BROAD SURFACE RIDGING IS ACROSS THE NW DISCUSSION WATERS. THIS RIDGING...IN CONJUNCTION WITH SEVERAL AREAS OF 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 IN OUR AREA FOR 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 29N BETWEEN 122W AND 135W BY SUN AFTERNOON...SLOWLY PROPAGATING TO THE SSE WITH SEAS UP TO 12 FT ALONG 30N BY EARLY MON. AN AREA OF FRESH TO STRONG NORTHERLY WINDS IS IN THE GULF OF CALIFORNIA ARE FROM 24N TO 28N BETWEEN TROUGHING OVER NW MEXICO AND THE RIDGING OVER THE NORTHERN WATERS. THESE WINDS IN THE GULF SHOULD DIMINISH EARLY THIS MORNING WITH THE NEXT ROUND OF FRESH TO STRONG NORTHERLIES PUSH THROUGH THE GULF TUE AND WED. THE GRIDDED FORECASTS FOR THE WINDS ARE BASED UPON A BLEND OF THE LATEST GFS AND ECMWF GLOBAL MODELS TOGETHER WITH THE OFFICIAL NHC WIND FIELD FORECAST FOR TROPICAL DEPRESSION EIGHTEEN-E. $$ CHRISTENSEN