000 AXPZ20 KNHC 231605 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC THU JAN 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1545 UTC. ...SPECIAL FEATURE... GULF OF TEHUANTEPEC GALE WARNING...N TO NE WINDS HAVE DIMINISHED TO 20-25 KT THROUGH THE GULF BASED IN PARTIAL ASCAT DATA FROM LATE LAST NIGHT. THESE WINDS ARE CONFINED TO THE N OF 15N BETWEEN 94W-96W. GFS MODEL GUIDANCE IS CONSISTENTLY INDICATES THAT THESE WINDS WILL CONTINUE TO DIMINISH THROUGH THIS EVENING AS THE PRES GRADIENT ACROSS SOUTHERN MEXICO WEAKENS. STRONG HIGH PRES BUILDING SOUTHWARD OVER EASTERN AND SOUTHERN MEXICO BEHIND A FAST-MOVING COLD FRONT IN THE WESTERN GULF OF MEXICO WILL INDUCE ANOTHER HIGH WIND EVENT IN THE REGION BEGINNING AROUND DAYBREAK ON FRI. WINDS WILL QUICKLY INCREASE FROM 10-15 KT TO 30- 35 KT BETWEEN 06Z AND 12Z ON FRI...AND TO 30-40 KT BY FRI EVENING. SEAS WILL RAPIDLY BUILD TO 10-15 SHORTLY AFTER THE GALES COMMENCE...AND TO 17 FT BY FRI EVENING. THIS EVENT IS FORECAST TO LAST THROUGH LATE SAT WITH THE POSSIBILITY OF WINDS BRIEFLY INCREASING TO JUST BELOW STORM FORCE. A PLUME OF 8-12 FT NE SWELL WILL SPREAD DOWNWIND FROM THE SOURCE REGION FRI NIGHT THROUGH SUN. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH IS NOT PRESENTLY IDENTIFIABLE. THE ITCZ AXIS EXTENDS FROM 06N88W TO 04N100W TO 05N110W...THEN RESUMES AT 10N127W TO 05N140W. NO SIGNIFICANT CONVECTION IS NOTED. ...DISCUSSION... AN UPPER TROUGH IS SEEN ON WATER VAPOR IMAGERY EXTENDING FROM AN ELONGATED UPPER LOW AT 31N128W SSE THROUGH 24N128W TO A SHARP BASE NEAR 08N123W. THE ASSOCIATED SURFACE TROUGH IS ANALYZED FROM 15N124W TO 08N125.5W. SCATTERED MODERATE TO STRONG CONVECTION IS NOTED FROM 11N TO 20N BETWEEN THE TROUGH AND 116W. MID/UPPER LEVEL RIDGING IS PRESENT E OF THE UPPER TROUGH...WHILE A SHARP RIDGE IS TO THE W OF THE UPPER TROUGH ROUGHLY ALONG 136W N OF 18N. A SHARP UPPER TROUGH IS W OF THIS RIDGE TO THE W OF THE AREA. THE UPPER TROUGH ALONG 31N128W 24N128W TO 08N123W WILL LIFT NE AND DAMPEN OUT OVER THE NEXT 24-30 HOURS AS THE TROUGH OF THE AREA MOVES INTO THE FAR WESTERN PORTION OF THE AREA. THE SURFACE TROUGH WILL TRACK NW THROUGH EARLY FRI...THEN TO THE NNE INTO SAT AHEAD OF THE APPROACHING UPPER TROUGH AND ASSOCIATED SURFACE COLD FRONT W OF THE AREA. EXPECT THE CURRENT SHOWER/TSTM ACTIVITY ASSOCIATED WITH THE SURFACE TROUGH TO PERSIST THROUGH MOST OF SAT BEFORE DIMINISHING IN AREAL COVERAGE. THE SURFACE COLD FRONT ASSOCIATED WITH THE SHARP UPPER TROUGH W OF THE AREA IS FORECAST TO WEAKEN AS IT MOVES TO A POSITION FROM 32N137W TO 20N140W BY EARLY FRI...AND WEAKEN FURTHER TO A TROUGH FROM 32N135W TO 28N140W BY EARLY ON SUN. LARGE LONG-PERIOD NW SWELL WITH PERIODS OF 18-21 SECONDS BEING GENERATED BY THE PARENT LOW STORM CENTER) OF THE AFOREMENTIONED COLD FRONT HAVE BEGUN TO INVADE THE FAR NW PORTION OF THE FORECAST AREA WITH SEAS IN THE RANGE OF 12-19 FT. SEAS WILL QUICKLY BUILD TO NEAR 20 FT IN THE FAR NW CORNER THIS AFTERNOON BEFORE SUBSIDING TO AROUND 15 FT ON FRI. ELSEWHERE NW OF A LINE FROM 30N125W TO 03N140W SEAS ARE FORECAST TO BE IN THE 8-14 FT RANGE THROUGH THE NEXT 24 HOURS DUE TO THE LARGE NW SWELL TRAIN MOVING INTO THE NW PORTION. THESE SWELLS ARE FORECAST BY WAVEWATCH TO REACH TO NEAR 110W BY EARLY ON SUN. GAP WINDS... GULF OF PAPAGAYO...THE PRES GRADIENT BETWEEN HIGH PRESSURE IN THE GULF OF MEXICO AND LOWER PRES ASSOCIATED WITH THE MONSOON TROUGH CONTINUES TO PRODUCE DIURNAL PULSES OF NE WINDS TO 20-30 KT DOWNWIND FROM PAPAGAYO TO NEAR 89W-90W. THESE WIND CONDITIONS ARE FORECAST TO LAST THROUGH THE NEXT 48 HOURS. WIND-DRIVEN SEAS WILL BUILD TO 8-10 FT DURING PEAK WINDS...THEN SUBSIDE TO 6-7 FT. GULF OF PANAMA...ASCAT DATA FROM THIS MORNING HIGHLIGHTED N WINDS OF 20-30 KT THROUGH THE GULF...AND S FROM THERE TO 05N AS HIGH PRES IN THE NW CARIBBEAN CONTINUES TO INDUCE THE RESPONSIBLE TIGHT PRES GRADIENT. THE STRONGEST WINDS WILL OCCUR DURING LATE NIGHT AND EARLY MORNING HOURS... ENHANCED BY NOCTURNAL DRAINAGE FLOW. $$ AGUIRRE