000 AXPZ20 KNHC 281601 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC MON DEC 28 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1545 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE ITCZ AXIS EXTENDS FROM 05N90W TO 07N106W TO 07N113W TO 07N129W TO BEYOND 04N140W. SCATTERED MODERATE CONVECTION IS WITHIN 60 NM N OF THE AXIS BETWEEN 130W-138W. ...DISCUSSION... RATHER QUIET CONDITIONS CONTINUE OVERALL ACROSS THE AREA AS HIGH PRESSURE DOMINATES. WATER VAPOR IMAGERY SHOWS MODERATE TO STRONG SUBSIDENCE SPREADING EASTWARD W OF 117W...WHILE A SUBTROPICAL JET STREAM BRANCH OVER THE E CENTRAL PART OF THE AREA IS CHANNELING AMPLE DEEP TROPICAL MOISTURE IN THE FORM OF BROKEN TO OVERCAST CLOUDS EASTWARD FROM 12N-22N E OF 120W. A SHORTWAVE TROUGH IS SWINGING EASTWARD THROUGH THE SOUTHERN PORTION OF THE LONGWAVE TROUGH ALONG 116W. THIS FEATURE WORKING ON THE JET STREAM ENERGY AND THE ALREADY PRESENT MOISTURE IS TRIGGERING OFF SCATTERED TSTMS FROM 09N-11N. SCATTERED SHOWERS AND ISOLATED TSTMS ARE NOTED FROM 11N-17N BETWEEN 100W-114W. THIS ACTIVITY IS EXPECTED TO LAST INTO WED. A 1031 MB HIGH PRESSURE SYSTEM IS CENTERED N OF THE DISCUSSION AREA AT 36N140W WITH A RIDGE STRETCHING SE TO 32N131W TO NEAR 22N115W. HIGH PRESSURE COVERS THE AREA N OF 20N W OF 115W. THE TAIL-END OF A WEAKENING COLD FRONT EXTENDS FROM 32N124W TO 30N129W. A TIGHT PRESSURE GRADIENT BETWEEN THE FRONT AND THE RIDGE IS BRINGING NW 20-25 KT N OF THE FRONT WITH SEAS TO 8 FT. THE FRONT IS FORECAST TO CONTINUE TO WEAKEN AS IT REACHES FROM NEAR 32N113W TO 27N120W BY EARLY MON...THEN DISSIPATE BY EARLY TUE. THE PRESSURE GRADIENT BETWEEN THE SUBTROPICAL RIDGE AND LOWER PRESSURE IN THE VICINITY OF THE ITCZ CONTINUES TO SUPPORT AN AREA OF FRESH TO STRONG TRADE WINDS FROM 6N-242N W OF 133W BASED ON ASCAT DATA FROM LAST NIGHT. SEAS WITHIN THIS AREA OF TRADES ARE 9-11 FT EXCEPT 10-12 FT IN NW SWELL N OF 29N W OF 137W. THE TIGHT GRADIENT IS EXPECTED TO CHANGE LITTLE THROUGH EARLY TUE...THEN SLACKEN TUE AFTERNOON AS THE 1031 MB HIGH CENTER SHIFTS EASTWARD AND WEAKENS. THIS WILL ALLOW FOR THE TRADES TO DIMINISH TO 15-20 KT. SEAS AT THAT TIME ARE FORECAST TO BE IN THE 8-10 FT RANGE IN MIXED NE AND NW SWELL...EXCEPT 10-11 FT PRIMARILY IN NW SWELL N OF 28N E OF 125W AND FROM 14N-20N W OF 135W. BY 48 HOURS...WINDS ARE FORECAST TO BE 15-20 KT BETWEEN A LINE FROM 30N116W TO 13N119W TO 08N125W TO 02N140W...AND ANOTHER LINE FROM 32N127W TO 24N140W WITH SEAS 8-9 FT PRIMARILY IN NW SWELL...EXCEPT FOR SEAS TO 10 FT W OF 130W. GAP WINDS... GULF OF TEHUANTEPEC...CURRENT CONDITIONS ARE QUIET. THE NEXT PULSE OF STRONG GAP WINDS IS EXPECTED THIS EVENING AS A COLD FRONT MOVES THROUGH THE SW GULF OF MEXICO. WINDS WILL BRIEFLY INCREASE TO STRONG TO NEAR GALE FORCE WITH SEAS BUILDING TO 9 FT. WINDS AND SEAS WILL DIMINISH QUICKLY BY TUE EVENING. BEYOND 48 HOURS...ADDITIONAL GAP WIND PULSE IS EXPECTED TO START WED NIGHT FOLLOWED BY ANOTHER GALE FORCE GAP WIND EVENT FRI NIGHT AS A REINFORCING PUSH OF COLD AIR OCCURS ACROSS THE WESTERN GULF OF MEXICO. GULF OF PAPAGAYO...STRONG TO GALE FORCE EASTERLY TRADE WIND FLOW ACROSS THE SW CARIBBEAN SEA IS RESULTING IN STRONG EASTERLY GAP WINDS THROUGH THE GULF OF PAPAGAYO...BUT ARE EXPECTED TO DIMINISH THIS AFTERNOON. THESE WINDS WILL PULSE DURING THE OVERNIGHT HOURS THROUGH MOST OF THE WEEK. THE CARIBBEAN WINDS WILL ALSO SEND PULSES OF MODERATE TO FRESH NORTHERLY GAP WINDS ACROSS THE ISTHMUS OF PANAMA INTO THE GULF OF PANAMA DURING THE EVENING TO EARLY MORNING HOURS THROUGH MOST OF THE WEEK. $$ AGUIRRE