000 AXPZ20 KNHC 181000 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC TUE MAR 18 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0930 UTC. ...SPECIAL FEATURES... THE CURRENT GALE WARNING IN EFFECT FOR THE GULF OF TEHUANTEPEC FOR N TO NE WINDS OF 30-35 KT IS SET TO EXPIRE BY DAYBREAK THIS MORNING AS THE TIGHT PRES GRADIENT OVER SOUTHEASTERN MEXICO SLACKENS. THE CURRENT GALE FORCE WINDS WILL QUICKLY DIMINISH TO 10-15 KT THIS AFTERNOON. SEAS OF 12 FT WILL SUBSIDE TO LESS THAN 8 FT BY THIS AFTERNOON. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A WEAK MONSOON TROUGH EXTENDS FROM 06N94W TO 04N110W. SOME LOW LEVEL WINDS ARE FLOWING INTO THE SEASONAL SOUTHERN HEMISPHERIC "SECOND" ITCZ ALONG 04-05S BETWEEN 94W-107W. THE MONSOON TROUGH TRANSITIONS TO THE ITCZ NEAR 04N110W TO 05N125W TO 04N140W. NO SIGNIFICANT CONVECTION WAS NOTED. ...DISCUSSION... A SHARP UPPER TROUGH EXTENDS FROM THE SE U.S. SW ACROSS NE MEXICO TO A SHEARED MID/UPPER LEVEL CYCLONE NEAR 12N115W...AND SE TO THE EQUATOR AT 108W. BROAD UPPER LEVEL RIDGING IS NOTED TO THE W OF THE TROUGH AND CYCLONE. A SMALL UPPER LEVEL ANTICYCLONE IS OVER SOUTHERN COSTA RICA WITH ITS ASSOCIATED ANTICYCLONIC ENVELOP COVERING THE EASTERN PORTION OF THE AREA E OF THE UPPER TROUGH AND MID/UPPER CYCLONE. MODERATE TO STRONG SUBSIDENCE IS NOTED ON SATELLITE WATER VAPOR COVERING MUCH OF THE CENTRAL AND EASTERN PORTIONS OF THE AREA. DEEP LAYERED WLY FLOW ALOFT IS NOTED BETWEEN THE UPPER TROUGH AND THE BROAD UPPER LEVEL RIDGING. THE CUT-OFF LOW IS FORECAST TO WEAKEN THROUGH LATE THU AS IT SLOWLY DROPS TO THE SE. DIVERGENCE LOCATED TO THE SE OF THIS LOW HAS BEEN HELPING TO SUSTAIN AN AREA OF BROKEN TO OVERCAST MULTILAYERED CLOUDS WITH SCATTERED SHOWERS AND ISOLATED TSTMS FROM 07N TO 14N BETWEEN 107W-115W. THIS ACTIVITY IS EXPECTED TO DIMINISH OVER THE NEXT 24-48 HOURS AS THE CUT-OFF LOW WEAKENS AND THE UPPER DIVERGENCE FADES OUT. WIDELY SCATTERED SHOWERS AND TSTMS OVER THE FAR EASTERN PORTION ARE SEEN FROM 04N- 06N BETWEEN 85W-89W. THIS ACTIVITY IS UNDER THE UPPER LEVEL ANTICYCLONIC FLOW THERE. ABUNDANT MODERATE SUBSIDENCE ALOFT AND ASSOCIATED DRY AIR WILL KEEP THIS ACTIVITY TO A MINIMUM THROUGH THE NEXT 48 HOURS. AT THE SURFACE...BROAD RIDGING EXTENDS INTO THE AREA FROM THE NE PACIFIC...AND HAS WEAKENED SLIGHTLY DURING THE PAST 24-36 HOURS. THE RIDGE AXIS EXTENDS INTO THE AREA THROUGH 32N130W TO NEAR 21N122W. THE PRES GRADIENT TO THE S AND SW OF THE RIDGE IS SUPPORTING A ZONE OF NE-E 15-20 KT TRADES GENERALLY FROM NEAR 20N S TO THE ITCZ AND W OF ABOUT OF 120W WHERE SEAS ARE CURRENTLY 8 TO 10 FT PRIMARILY IN NW SWELL. A TIGHT PRES GRADIENT OVER THE NE WATERS IS PRODUCING NW 20-25 KT WINDS THERE WITH SEAS OF 10-11 FT. THE GRADIENT WILL WEAKEN THROUGH THIS AFTERNOON ALLOWING FOR THESE WINDS TO DIMINISH TO 15 KT. HOWEVER...SEAS WILL REMAIN LARGE...UP TO 9 FT...IN NW SWELLS. BY LATE TONIGHT...SEAS TO 9 FT IN NW SWELLS WILL BE CONFINED TO E OF A LINE FROM 30N128W TO 24N114W. BY LATE WED NIGHT...THESE SEAS ARE EXPECTED TO BE N OF 27N W OF 124W. GAP WINDS... GULF OF PAPAGAYO...HIGH PRES WILL BUILD SE AND S ACROSS THE GULF OF MEXICO AND NW CARIBBEAN WITH THE PRES DIFFERENCE BETWEEN IT AND LOWER PRES OVER FAR NW COLOMBIA AND THE SW CARIBBEAN SEA IS FORECAST TO INDUCE AN INITIAL SURGE OF NE-E 20-25 KT WINDS THROUGH THE GULF BEGINNING WED MORNING. MODEL GUIDANCE SUGGESTS THAT THESE PULSES WILL CONTINUE THROUGH THE NEXT 48 HOURS WITH POSSIBLE WIND GUSTS TO 30 KT...AND SEAS TO AROUND 9 FT. $$ AGUIRRE