000 AXPZ20 KNHC 012204 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC TUE DEC 01 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 2145 UTC. ...SPECIAL FEATURE... GULF OF TEHUANTEPEC GALE WARNING...NORTHERLY SURGES AT 20-25 KT ARE EXPECTED TONIGHT AND ON WED...THEN INCREASING TO 20-30 KT EARLY WED NIGHT...AND FURTHER INCREASING TO MINIMAL GALE FORCE LATE WED NIGHT. THE GRADIENT IS EXPECTED TO CONTINUE TO TIGHTEN THROUGHOUT THE DAY ON THU WITH 35-40 KT CONDITIONS AS FAR AS 180 NM SSW OF TEHUANTEPEC ON THU EVENING...AND 35-45 KT CONDITIONS AS FAR AS 240 NM SSW OF THE GULF AT SUNRISE ON FRI. THESE STRONG GALE CONDITIONS WILL THEN PERSIST THROUGH TUE NIGHT. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A 1006 MB SURFACE LOW IS ANALYZED OVER COLOMBIA AT 05N76W WITH A SURFACE TROUGH EXTENDING SW OVER THE TROPICAL PACIFIC FROM 04N77W TO 02N82W TO 03N86W. SCATTERED MODERATE ISOLATED STRONG STRONG CONVECTION IS OBSERVED E OF 84W WITHIN 120 NM EITHER SIDE OF THE TROUGH AXIS. SCATTEROMETER WINDS INDICATE THE ITCZ AXIS FORMS NEAR 05N90W...AND EXTENDS NW TO 06N97W...THEN WIGGLES WESTWARD THROUGH 04N111W TO AN EMBEDDED TROUGH AT 08N130W...WITH THE ITCZ THEN TURNING SW TO BEYOND 05N140W. THE EMBEDDED TROUGH EXTENDS N-S FROM 05N130W TO 11N129W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS OBSERVED WITHIN 180 NM E AND WITHIN 240 NM W OF TROUGH AXIS. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS NOTED WITHIN 180 NM EITHER SIDE OF THE ITCZ AXIS BETWEEN 96W- 101W...BETWEEN 105W-111W AND BETWEEN 115W AND 126W. ...DISCUSSION... A 1026 MB SURFACE HIGH IS ANALYZED NEAR 31N129W AND IS SHIFTING NE. THE PRESSURE GRADIENT BETWEEN THIS HIGH PRESSURE AND THE ITCZ IS SUPPORTING A LARGE AREA OF STRONG NE TRADE WINDS...ROUGHLY ACROSS THE TROPICS FROM 10-22N W OF 125W WITH COMBINED SEAS OF 9- 13 FT. LONG PERIOD CROSS EQUATORIAL SWELL AND LONG PERIOD NW SWELL ARE MIXING WITH FRESH TRADES ELSEWHERE W OF A LINE FROM THE NORTHERN BAJA CALIFORNIA PENINSULA TO EQUATOR AT 105W RESULTING IN COMBINED SEAS OF 8-11 FT. AS THE HIGH SHIFTS NE THE GRADIENT WILL RELAX WITH THE AREA OF STRONG TRADES SHIFTING TO THE W OF 133W ON THU. SOUTHERLY FLOW WILL INCREASE TO 20-30 KT ACROSS THE NW DISCUSSION WATERS ON WED IN ADVANCE OF A COLD FRONT ARRIVING AT 32N140W ON WED. ALTHOUGH THE FAST MOVING FRONT WILL WEAKEN CONSIDERABLY BY THE TIME IT REACHES THE NORTHERN BAJA ON THU NIGHT IT WILL BE ACCOMPANIED BY POST-FRONTAL LONG PERIOD NW SWELL WHICH WILL DRIVE THE SEAS HEIGHTS UP TO 18 FT NEAR 32N140W ON THU. SEAS 12 FT OR GREATER ARE FORECAST W OF A LINE FROM 32N122W TO 13N140W ON FRI. GULF OF CALIFORNIA...A STRONG GRADIENT WILL MAINTAIN NW-N 20-30 KT WINDS ACROSS THE GULF OF CALIFORNIA THROUGH EARLY WED...THEN 20-25 KT CONDITIONS WILL PERSIST THROUGH THU AFTERNOON BEFORE DIMINISHING TO 15-20 KT. EXPECT SEAS TO BUILD TO 10 FT IN LONG FETCH OPEN AREAS BETWEEN 25-27N. $$ NELSON