000 AXPZ20 KNHC 282221 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC SAT NOV 28 2015 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 2130 UTC. ...SPECIAL FEATURES... GULF OF TEHUANTEPEC GALE WARNING...A HIGH PRESSURE RIDGE EXTENDING FROM THE SOUTHEASTERN U.S. TO THE YUCATAN PENINSULA IS COMBINING WITH A SHARP AND HIGH AMPLITUDE TROUGH ACROSS THE ATLANTIC FROM JUST WEST OF BERMUDA TO HISPANIOLA...WHICH IS PROMOTING FRESH N TO NE WINDS ACROSS THE W CARIBBEAN AND INTO CENTRAL AMERICA. THIS ALIGNMENT AND THE ASSOCIATED PRESSURE GRADIENT CONTINUES TO SUPPORT FRESH TO STRONG PULSES OF GAP WINDS ACROSS SEVERAL GAP PRONE AREAS OF PACIFIC CENTRAL AMERICA...AND 20-30 KT NORTHERLY WINDS ACROSS THE GULF OF TEHUANTEPEC AND DOWNSTREAM TO NEAR 13N97W. A WEAK COLD FRONT WILL BE NUDGED INTO THE NW GULF OF MEXICO TONIGHT AND SUN...WITH STRONG HIGH PRESSURE BEHIND IT BUILDING SOUTHWARD INTO CENTRAL MEXICO...AND WILL FURTHER TIGHTEN THE PRESSURE GRADIENT ACROSS TEHUANTEPEC. THIS WILL LEAD TO NORTHERLY GALES DEVELOP TONIGHT AROUND 0600 UTC ACROSS THE TEHUANTEPEC REGION...AND IS EXPECTED TO CONTINUE FOR 24-30 HOURS THROUGH MON MORNING AROUND 1200 UTC. WINDS THERE MAY PEAK NEAR 40 KT ON SUNDAY AND SUNDAY NIGHT... WITH MAXIMUM SEAS BUILDING 12-14 FT. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM 06N78W TO 04N81W TO 05N95W. THE ITCZ EXTENDS FROM 09N119W TO 04N140W. SCATTERED MODERATE TO STRONG CONVECTION NOTED FROM 05N TO 11N BETWEEN 108W TO 132W. ...DISCUSSION... POST-TROPICAL CYCLONE SANDRA WAS LOCATED OFFSHORE OF THE SOUTHERN TIP OF BAJA CALIFORNIA NEAR 22.3N 108.8W...MOVING N-NE AT 8 KT. A FLARE-UP OF CONVECTION NEAR THIS LOW HAS OCCURRED THIS AFTERNOON...WITH ISOLATED TO SCATTERED STRONG CONVECTION NOTED WITHIN 120 NM ACROSS THE NE QUADRANT OF THE CENTER. OTHERWISE...THE REMNANTS OF SANDRA REMAIN A LOW LEVEL CLOUD SWIRL THAT IS GRADUALLY BECOMING ELONGATED NE TO SW. AFTERNOON SCATTEROMETER DATA SHOWED SE WINDS 20-30 KT WITHIN 180 NM ACROSS THE NE QUADRANT AND S TO SW WINDS 20-25 KT WITHIN 150 NM ACROSS THE SE QUADRANT. SEAS REMAIN ROUGH AND CONFUSED ACROSS THE SOUTHERN GULF OF CALIFORNIA S OF 25.5N...AT 8 TO 12 FT. THE REMNANT LOW WILL MOVE N-NE DURING THE NEXT 24 HOURS AND IS EXPECTED TO REACH THE COAST OF CENTRAL SINALOA ON SUNDAY AS IT GRADUALLY WEAKENS AND SPINS DOWN. LOOK FOR MARINE CONDITIONS ACROSS THE SOUTHERN GULF OF CALIFORNIA TO GRADUALLY IMPROVE DURING THIS TIME...BUT WILL IMMEDIATELY BE REPLACED BY N-NW WINDS OF 20-25 KT SPILLING DOWN THE ENTIRE LENGTH OF THE GULF SUN AFTERNOON AND NIGHT...AND CONTINUE THROUGH TUE...WITH SEAS BUILDING TO 8-10 FT FAR S PORTIONS. A WEAKENING COLD FRONT STRETCHES FROM LOW PRES N OF THE AREA NEAR 36N129W TO 32N129W TO 30N134W TO 30N143W. WEAK HIGH PRES BEHIND FRONT CENTERED NEAR 33N140W...WITH A STRONGER COLD FRONT NW OF THE HIGH. A BROAD RIDGE PREVAILS OVER NORTHERN WATERS N OF 18N W OF 115W. THE PRESSURE GRADIENT BETWEEN THE RIDGE AND ITCZ IS SUPPORTING 20-25 KT NE WINDS FROM 15N-21N W OF 126W. LARGE AREA OF 8-12 FT SEAS FROM SWELL GENERATED BY SANDRA...NW SWELL SWEEPING INTO THE AREA FROM THE CENTRAL PACIFIC...AND FRESH NE TRADE SWELL EXISTS W OF 115W-120W. THE AREA OF FRESH TO STRONG TRADES IS EXPECTED TO SHIFT WEST-SOUTHWESTWARD AS RIDGING BUILDS SOUTHEASTWARD ACROSS THE NORTHERN FORECAST WATERS THROUGH SUN. A NEW COLD FRONT WILL ENTER THE NW FORECAST WATERS MONDAY MORNING WITH NW SWELL W OF THE BOUNDARY RAISING SEAS TO 13 FT. GAP WINDS... AS MENTIONED ABOVE...THE PRESSURE PATTERN ACROSS THE W ATLANTIC...GULF OF MEXICO...AND WESTERN CARIBBEAN HAS SET UP TO PRODUCE IDEAL CONDITIONS FOR NORTHEAST WINDS TO BLOW ACROSS CENTRAL AMERICA AND THROUGH THE GAP WIND PRONE AREAS ALONG THE PACIFIC COASTS. THE GULF OF PAPAGAYO REGION IS EXPECTED TO PULSE TO 20-25 KT EACH EVENING THROUGH MORNING FOR THE NEXT FEW DAYS...POSSIBLY PEAKING NEAR 30 KT SUN AND MON MORNINGS. MEANWHILE LOOK FOR THE GULF OF FONSECA TO BLOW TO AROUND 20 KT EACH OF THE NEXT NIGHT AND MORNINGS...WHILE NORTHERLY WINDS SPILL ACROSS PANAMA AND PRODUCE N WINDS AROUND 20 KT ACROSS AND DOWNSTREAM OF THE GULF OF PANAMA. $$ STRIPLING