000 AXPZ20 KNHC 152149 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC MON FEB 15 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...A 20-30 KT NORTHERLY SURGE WILL BEGIN LATE TONIGHT AND THEN GRADUALLY INCREASE THROUGHOUT THE DAY ON TUE REACHING MINIMAL GALE STRENGTH AROUND SUNSET ON TUE. THE GALE WILL BRIEFLY STRENGTHEN TO 30-40 KT LATE WED NIGHT INTO EARLY THU...WITH GALE CONDITIONS PERSISTING THROUGH SUNRISE ON SAT. EXPECT SEAS TO BUILD TO ABOUT 15 FT NEAR 15N95.5W ON WED NIGHT. ...INTERTROPICAL CONVERGENCE ZONE AND TROPICAL TROUGHS... A MID TO UPPER LEVEL CYCLONE AT 18N138W HAS AN ASSOCIATED SURFACE INVERTED TROUGH EXTENDING FROM 13N139W TO 20N137W AND IS MOVING W WITH TIME. SCATTERED MODERATE CONVECTION IS ENHANCED E OF THE TROUGH WITHIN 300 NM OF 16.5N130W. STRONG E-SE WINDS... WITH 9-11 FT SEAS...ARE OBSERVED TO THE N OF 17N WITHIN 360 NM E OF TROUGH. THIS TROUGH SHOULD MOVE W OF AREA TONIGHT WITH WINDS DIMINISHING TO 20 KT OR LESS WITHIN THIS DISCUSSION AREA. A SECOND LOW LEVEL TROUGH IS NOTED IN THE DEEP TROPICS FROM 02N133W TO 10N130W WITH ISOLATED MODERATE TO STRONG CONVECTION OBSERVED TO THE N OF 05N WITHIN 240 NM E OF THE TROUGH. STRONG NE WINDS ARE OBSERVED WITHIN 240 NM NW OF LINE EXTENDING NE FROM 06N138W TO 12N130W...WITH SEAS OF 11-14 FT. THIS TROUGH WILL ALSO MOVE W OF THE AREA ON TUE LEAVING A SMALL AREA OF STRONG NE WINDS FROM 08-14N BETWEEN 130-138W WITH SEAS OF 10 FT. THE ASSOCIATED WINDS WILL THEN DIMINISH TO 20 KT OR LESS ON WED. SCATTEROMETER WINDS INDICATE THAT THE ITCZ FORMS NEAR 05N88W AND EXTENDS WESTWARD TO 04N130W WHERE THE LOW LEVEL FLOW IS INTERRUPTED BY THE SECOND TROUGH PREVIOUSLY MENTIONED. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS NOTED ALONG THE ITCZ WITHIN 150 NM EITHER SIDE OF A LINE FROM 05.5N96.5W TO 03N118W TO 06N128W. THE ITCZ RESUMES SW OF THE SECOND TROUGH FROM 03N134W TO BEYOND 01N140W WITH SCATTERED MODERATE ISOLATED STRONG CONVECTION OBSERVED WITHIN 30 NM EITHER SIDE OF A LINE FROM 03N137W TO 02N140W. ...DISCUSSION... ELSEWHERE N OF 15N E OF 120W... A SURFACE RIDGE EXTENDS SE FROM 25N120W TO BEYOND 15N101W. THE PRESSURE GRADIENT IS RELAXING WITH GENTLE NORTHERLY WINDS EXPECTED ACROSS THE OPEN PACIFIC WATERS BETWEEN 110-120W TONIGHT INTO TUE. A WEAK SURFACE HIGH WILL DEVELOP ALONG THE RIDGE NEAR 22N110W LATE TUE WITH LIGHT AND VARIABLE WINDS W OF 107W THROUGH WED AS A SECOND SURFACE HIGH DRIFTS E INTO THE AREA NEAR 27N120W...AND THEN SHIFTS NE TO OVER NW MEXICO ON WED NIGHT WITH A WEAK COLD FRONT/TROUGH PASSING E ACROSS THE WATERS N OF 24N ON WED NIGHT THROUGH THU NIGHT. A RIDGE WILL SET UP IN THE WAKE OF THE FRONT FROM 27N120W TO 15N104W ON THU NIGHT AND THEN MOVE LITTLE THROUGH THE WEEKEND. COMBINED SEAS OF 4-7 FT CURRENTLY ACROSS THE PAC WATERS BETWEEN 107-120W WILL CONTINUE TO SUBSIDE WITH 3-6 FT CONDITIONS EXPECTED ON TUE AND WED. POST-FRONTAL NW SWELL IN THE FORM OF 6- 9 FT SEAS WILL ARRIVE AT 30N120W LATE THU NIGHT...REACH THE PACIFIC COAST OF THE NORTHERN BAJA PENINSULA ON FRI AND THE SOUTHERN COAST OF BAJA ON SAT. FRESH TO LOCALLY STRONG NW WINDS ARE EXPECTED ACROSS THE GULF OF CALIFORNIA WATERS TO THE N OF 26N W OF 110W TONIGHT...THEN THE NW FLOW WILL DIMINISH TO GENTLE BY TUE NIGHT BECOMING LIGHT AND VARIABLE ON WED NIGHT. S OF 15N E OF 110W...MODERATE E TO SE WINDS DOMINATE THE AREA W OF 93W WITH COMBINED SEAS OF 7-1O FT IN SUBSIDING NE...S AND NW SWELL. THESE SEAS SHOULD SUBSIDE TO LESS THAN 8 FT BY WED MORNING. STRONG TO NEAR GALE FORCE NE PULSES ARE EXPECTED EACH NIGHT ACROSS AND DOWNSTREAM OF THE GULF OF PAPAGAYO. ANOTHER GALE WILL DEVELOP IN THE GULF OF TEHUANTEPEC LATE TUE...WITH THE GALE CONDITIONS SPREADING S INTO THE AREA N OF 13N BETWEEN 94- 97W ON WED...WITH THE TONGUE OF STRONG TO NEAR GALE WINDS SPREADING S TO NEAR 10N100W ON THU. SEAS FROM BOTH GAP EVENTS WILL MERGE AGAIN WITH 7-11 FT SEAS ACROSS THE AREA W OF 93W LATE IN THE WEEK. PULSES OF FRESH NORTHERLY WINDS WILL SPREAD S FROM THE GULF OF PANAMA TO ALONG ABOUT 04N TONIGHT AND TUE NIGHT WITH GUIDANCE SUGGESTING STRONG N-NE WINDS WILL RESUME ON WED NIGHT...WITH ASSOCIATED SEAS BUILDING TO ABOUT 10 FT NEAR 05N82W. ELSEWHERE FROM THE EQUATOR TO 32N E OF 140W...MIXING SWELL RESULTING IN 8 TO 11 FT COMBINED SEAS ACROSS THE TROPICS WILL GRADUALLY SUBSIDE THROUGH MID WEEK. EXPECT A W-E ORIENTATED RIDGE FROM 25N140W TO 26N120W ON TUE NIGHT WITH A TROUGH...OR WEAK COLD FRONT RAPIDLY SWEEPING E ACROSS THE WATERS N OF THE RIDGE ACCOMPANIED BY STRONG NW FLOW N OF 30N W OF THE FRONT LATE TUE NIGHT INTO WED. ANOTHER ROUND OF LARGE NW SWELL IN THE FORM OF 8-13 FT SEAS WILL PROPAGATE E ACROSS THE WATERS N OF 22N ON WED-FRI. STRONG SW FLOW WILL DEVELOP ACROSS THE FAR NW PORTION ON SAT IN ADVANCE OF ANOTHER COLD FRONT. $$ NELSON