000 AXPZ20 KNHC 082139 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC FRI MAR 06 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 2100 UTC. ...SPECIAL FEATURES... GULF OF TEHUANTEPEC GALE WARNING...THE MOST RECENT SCATTEROMETER PASS INDICATES MINIMAL GALE FORCE WINDS ACROSS THIS GULF. THE PERSISTENT STRONG HIGH PRES CELL OVER NE MEXICO FROM THE PAST FEW DAYS HAS WEAKENED AS IT SHIFTS SOUTHWARD. THE ASSOCIATED TIGHT PRES GRADIENT OVER THE ISTHMUS OF TEHUANTEPEC HAS ALSO WEAKENED AND WINDS ARE EXPECTED TO BE BELOW GALE FORCE THIS EVENING. THE WINDS WILL FURTHER DIMINISH ON MON WITH NORTHERLY WINDS OF 15-20 KT BY MON AFTERNOON. LOOKING AHEAD...THE NEXT TEHUANTEPEC GAP WIND EVENT IS EXPECTED TO BEGIN WITH 20-25 KT NORTHERLY WINDS LATE TUE NIGHT AS REINFORCING HIGH PRES BUILDS SWD IN THE WAKE OF A WESTERN GULF OF MEXICO COLD FRONT. MODEL GUIDANCE HAS BEEN CONSISTENTLY FORECASTING THESE WINDS TO INCREASE TO MINIMAL GALE FORCE LATE WED NIGHT INTO THU MORNING. GALE CONDITIONS WILL LIKELY PERSIST THROUGH FRI MORNING. GULF OF PAPAGAYO GALE WARNING...A RECENT WINDSAT PASS SHOWED NE TO E WINDS OF 20-30 KT EXTENDING DOWNWIND OF THE GULF OF PAPAGAYO TO NEAR 08N95W WHILE AN ALTIMETER PASS INDICATED SEA HEIGHTS OF AROUND 10 FT. AT 2100 UTC...LIBERIA LOCATED IN NORTHERN COSTA RICA IS REPORTING SUSTAINED WINDS OF 26 KT WITH GUSTS TO 39 KT. MINIMAL GALE CONDITIONS ARE EXPECTED TO DEVELOP AGAIN LATE TONIGHT DURING MAXIMUM DRAINAGE FLOW AND CONTINUE THROUGH EARLY MON MORNING...THEN QUICKLY DIMINISH TO 20 KT OR LESS ON MON EVENING. GUIDANCE HAS BECOME MORE AGGRESSIVE OVER THE PAST 24 HOURS AND NOW SUGGESTS A MAX OF 30 KT...NEAR GALE...WINDS LATE MON NIGHT INTO EARLY TUE MORNING. IN THE GULF OF FONSECA...WINDS ARE NOT EXPECTED TO EXCEED 15-20 KT TONIGHT...AND REACH ONLY 10-15 KT ON MON NIGHT. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE ITCZ EXTENDS FROM 04N89W TO 03N100W TO 04N124W THEN RESUMES W OF A TROUGH AT 04N130W TO BEYOND 03N140W. THE TROUGH AXIS EXTENDS FROM 08N126W TO 03N127W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS SEEN ALONG THE TROUGH AXIS FROM 04.5N TO 05N BETWEEN 125W AND 128W. A SECOND ITCZ IS SOUTH OF THE EQUATOR AND STRETCHES FROM 05S94W TO 03S110W TO 03S120W. NO SIGNIFICANT CONVECTION. ...DISCUSSION... ALOFT...A RIDGE/TROUGH/RIDGE PATTERN DOMINATES THE FORECAST REGION. THE SECOND RIDGE ALSO COVERS SE MEXICO AND CENTRAL AMERICA. A SURFACE RIDGE EXTENDS FROM A 1024 MB HIGH PRESSURE LOCATED N OF AREA NEAR 38N130W TO 20N110W. THE TRADE WINDS HAVE INCREASED BETWEEN THE SOUTHERN PERIPHERY OF THE RIDGE AND THE ITCZ AXIS. A COUPLE OF SCATTEROMETER PASSES PROVIDED OBSERVATIONS OF 20-25 KT NE TO E WINDS FROM 06N TO 16N W OF 118W. THE PRESSURE GRADIENT WILL GRADUALLY RELAX OVER THE NEXT COUPLE OF THE DAYS AS THE RIDGE BREAKS DOWN IN RESPONSE TO A FRONTAL SYSTEM THAT MOVES INTO THE FAR WESTERN PART OF THE AREA. BY TUE AFTERNOON...NE TO E 20-25 KT WINDS ARE FORECAST FROM 06N TO 11N W OF 135W WITH SEAS OF 9-11 FT. REINFORCING NE SWELL...ORIGINATING FROM PREVIOUS GULF OF TEHUANTEPEC STORM FORCE WINDS...AND STRONG TO GALE FORCE WINDS IN THE GULF OF PAPAGAYO WILL CONTINUE TO PROPAGATE WSW INTO THE TROPICAL WATERS S OF ABOUT 13N...AND SPREAD WWD ACROSS THE WATERS BETWEEN 93W-120W OVER THE NEXT 24- 48 HRS. CROSS EQUATORIAL SOUTHERLY SWELLS ARE FORECAST TO REACH THE SOUTHERN WATERS BY EARLY MON AS PROJECTED BY WAVEWATCH MODEL GUIDANCE. A WEAK COLD FRONT REMAINS OVER THE FAR NW WATERS AND LIES FROM 30N136W TO A 1013 MB LOW PRES LOCATED W OF AREA NEAR 25N143W. MAINLY GENTLE WINDS ARE OBSERVED ON EITHER SIDE OF THE FRONT WITH SEAS TO 9 FT IN NW SWELL. THE FRONT WILL MOVE W OF THE AREA TONIGHT. EXPECT INCREASING SOUTHERLY WINDS ACROSS THE NW WATERS ON MON AS ANOTHER COLD FRONT APPROACHES FROM THE WEST. MARINE GUIDANCE SUGGESTS SE-S WINDS OF 20-25 KT AND SEAS OF 8 TO 10 FT N OF 20N W OF 137W BY MONDAY MORNING. A TOUGH PERSISTS NEAR THE COAST OF COLOMBIA AND CURRENTLY EXTENDS FROM A 1006 MB LOW PRES NEAR 06N75W TO THE EQUATOR AT 81W. SCATTERED SHOWERS ARE POSSIBLE NEAR THIS TROUGH. .GULF PANAMA...FRESH TO STRONG NORTHERLY WINDS ARE FUNNELING INTO THE GULF OF PANAMA FROM THE CARIBBEAN SEA. AN EARLIER ASCAT PASS CONFIRMED THE PRESENCE OF THESE WINDS SPREADING AS FAR SOUTH AS 04N. WINDS WILL PULSE AGAIN TO 25 KT LATE TONIGHT INTO EARLY MON MORNING...THEN WILL DIMINISH TO 20 KT OR LESS BY MON AFTERNOON. EXPECT BUILDING SEAS TO AROUND 9 FT WITH THIS GAP WINDS EVENT. $$ GR