000 AXPZ20 KNHC 230346 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC TUE DEC 23 2014 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0315 UTC. ...SPECIAL FEATURE... GULF OF TEHUANTEPEC...A COLD FRONT WILL MOVE ACROSS THE GULF OF MEXICO ON TUE THROUGH WED NIGHT. EXPECTING LIGHT SOUTHERLY WINDS ACROSS THE GULF OF TEHUANTEPEC THROUGH LATE TUE NIGHT. NORTHERLY 20-30 KT WINDS WILL INITIALLY SURGE THROUGH THE ISTHMUS OF TEHUANTEPEC EARLY WED MORNING...THEN RAPIDLY INCREASE TO GALE FORCE BY WED EVENING AND THEN CONTINUE THROUGH THU MORNING. EXPECT THE NORTHERLY FLOW TO DIMINISH BELOW 20 KT ON FRI. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS SW FROM THE PACIFIC COAST OF COLOMBIA AT 05N77W TO 03.5N81W...THEN TURNS NW TO 05.5N86W WHERE SCATTEROMETER WINDS INDICATE A TRANSITION TO AN ITCZ WHICH CONTINUES WNW TO AN EMBEDDED TROUGH AT 114W...THEN THE ITCZ AXIS TURNS WSW TO BEYOND 06N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION WITHIN 45 NM EITHER SIDE OF A LINE FROM 09N105W TO 08N117W. THE EMBEDDED TROUGH EXTENDS FROM 08N114W TO 15N110W WITH SCATTERED MODERATE ISOLATED STRONG CONVECTION NOTED WITHIN 240 NM EITHER SIDE OF A LINE FROM 10N113W TO 18N101W WITH FREQUENT LIGHTNING STRIKES IN THE CENTRAL PORTION OF THE AREA. ...DISCUSSION... A POSITIVE TILT UPPER LEVEL TROUGH EXTENDS SW FROM CENTRAL TEXAS ACROSS NORTHERN MEXICO TO WELL DEFINED BASE OVER THE PACIFIC AT 11N117W. AN UPPER ANTICYCLONE IS CENTERED OVER THE NW PORTION NEAR 32N130W WITH THE ASSOCIATED TS ANTICYCLONIC ENVELOPE OF DRY UPPER AIR DOMINATING THE DISCUSSION AREA TO THE N OF 21N W OF 110W. A PLUME OF UPPER MOISTURE...MOSTLY ORIGINATING FROM ITCZ CONVECTION IN THE CENTRAL PACIFIC...CONTINUES TO STREAM E ACROSS THE DISCUSSION AREA WITHIN 360 NM EITHER SIDE OF A LINE FROM 16N140W TO 08N116W...THEN THE PLUME TURNS NE IN RESPONSE TO THE PREVIOUSLY MENTIONED UPPER TROUGH...CONTINUING WITHIN 300 NM OF LINE FROM 12N109W TO OVER THE PACIFIC COAST OF MEXICO AT 17N101W...THEN NARROWS AS IT CONTINUES NE DISSECTING THE GULF OF MEXICO...AND CONTINUING NE ACROSS MOST OF FLORIDA. A SURFACE RIDGE EXTENDS SE FROM 32N132W TO 16N107W. THE GRADIENT IS MAINTAINING A SMALL AREA OF 20-25 KT N WINDS 11-13 FT SEAS ACROSS THE SUB-TROPICAL WATERS N OF 29N BETWEEN 122-126W THROUGH LATE TONIGHT BEFORE DIMINISHING BELOW 20 KT. NE-E 15-20 KT TRADES ARE OBSERVED ELSEWHERE ACROSS THE SUBTROPICS AND TROPICS BETWEEN THE ITCZ AND THE RIDGE...WITH A FEW PATCHES OF EMBEDDED 20-25 KT NE WINDS. OTHERWISE...THE LONG PERIOD NW SWELL WILL CONTINUES ACROSS THE DISCUSSION AREA W OF 103W...RESULTING IN COMBINED SEAS OF 8-11 FT. THIS LONG PERIOD NW SWELL WILL GRADUALLY SUBSIDE THROUGH THE MIDDLE OF THE WEEK. EXPECT THE CURRENT 6-9 FT CONDITIONS ALONG THE PACIFIC COAST OF THE BAJA PENINSULA TO SUBSIDE TO 4-7 FT ON TUE. HOWEVER...NE 20-25 KT WINDS ARE EXPECTED TO DEVELOP ACROSS THE PACIFIC COAST OF THE BAJA PENINSULA NEAR 29N EARLY TUE NIGHT...AND SPREAD SW TO NEAR 27N117W LATE TUE NIGHT...THEN DIMINISH TO 15 KT BY LATE WED. GULF OF CALIFORNIA...15-20 KT NW WINDS ARE EXPECTED TONIGHT. THE GRADIENT WILL TIGHTEN EARLY TUE WITH THE NW FLOW INCREASING TO 20-25 KT ACROSS THE NORTHERN GULF WATERS TUE MORNING...WITH 20-30 KT CONDITIONS SPREADING S ACROSS THE ENTIRE GULF OF CALIFORNIA BY TUE EVENING. SEAS WILL BUILD TO 8 FT IN LONG FETCH WATERS NEAR 27N ON TUE NIGHT. THE GRADIENT SHOULD RELAX ON WED WITH 15-20 KT FLOW EARLY WED NIGHT AND ONLY 10-15 KT NW FLOW BY EARLY THU. GULF OF PAPAGAYO...GUIDANCE INDICATES THAT THE NEXT NE 20-25 KT SURGE WILL BEGIN LATE THU AND EXTEND AS FAR SW AT 09N91W ON FRI AFTERNOON. $$ NELSON