000 AXPZ20 KNHC 231605 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC MON NOV 23 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 1500 UTC. ...SPECIAL FEATURES... GULF OF TEHUANTEPEC STORM WARNING...A STRONG COLD FRONT HAS MOVED THROUGH THE CHIVELA PASS ALLOWING COOL..DRY AIR TO MOVE INTO THE GULF OF TEHUANTEPEC. WINDS BEHIND THE FRONT HAVE RAPIDLY INCREASED TO STORM FORCE IN THE GULF OF TEHUANTEPEC. AN EARLIER ASCAT SATELLITE PASS SHOWED 40-45 KT N WINDS...BUT THE PASSAGE OF THIS AIR MASS OVER THE 30 DEGREE CELSIUS WATER WILL PROMOTE VERTICAL MIXING AND BRING THE STRONGER WINDS IN THE LOWER LEVELS OF THE ATMOSPHERE TO THE SURFACE. THE ADDITIONAL FACTOR OF NOCTURNAL DRAINAGE FLOW LIKELY ALLOWED WINDS TO REACH STORM FORCE ALREADY THIS MORNING. A STORM WARNING REMAINS IN EFFECT THROUGH EARLY TUE WITH MAXIMUM SEAS OF 18-21 FT EXPECTED. WINDS AND SEAS WILL DIMINISH TO MINIMAL GALE FORCE BY TUE AFTERNOON AND TO A FRESH TO STRONG BREEZE BY EARLY WED MORNING. BROAD LOW PRES WAS ANALYZED S-SW OF THE GULF OF TEHUANTEPEC ALONG THE MONSOON TROUGH NEAR 11N98W MOVING W-NW AROUND 5-10 KT. THE ESTIMATED MINIMUM CENTRAL PRESSURE WAS 1006 MB. SCATTERED MODERATE TO STRONG CONVECTION WAS NOTED WITHIN 180 NM W AND NW QUADRANTS. THE LOW WILL CONTINUE TO MOVE WESTWARD...MERGING INTO A PLUME OF STRONG NE TO E WINDS EMERGING OUT OF THE GULF OF TEHUANTEPEC LATER TODAY. THERE HAD BEEN SOME UNCERTAINTY THAT THE DRIER AIR ASSOCIATED WITH THE TEHUANTEPEC PLUME WOULD INHIBIT CONVECTIVE GROWTH...BUT LATEST TRENDS ON SATELLITE INDICATE FAIRLY ROBUST CONVECTION WITH A BAND BECOMING MORE ORGANIZED TO THE NORTH OF THE LOW CENTER. CONDITIONS WILL CONTINUE TO BECOME MORE CONDUCIVE FOR TROPICAL CYCLONE DEVELOPMENT. THERE IS A HIGH CHANCE THAT THIS SYSTEM WILL BECOME A TROPICAL CYCLONE BY EARLY WED MORNING. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH AXIS WAS ANALYZED FROM 08N78W TO LOW PRES NEAR 11N98W 1006 MB TO 07N110W TO 09N114W...THEN CONTINUES FROM 12N119W TO 09N125W.ITCZ AXIS FROM 09N125W TO LOW PRES 10N135W TO 06N140W. NO SIGNIFICANT CONVECTION NOTED. ...DISCUSSION... N OF 15N E OF 120W...THE DYING POST-TROPICAL REMNANT LOW RICK IS CENTERED ABOUT 300 NM WNW OF CLARION ISLAND MOVING FARTHER TO THE NW INTO COOLER WATER. NO CONVECTION IS NOTED WITH THIS LOW...BUT AN EARLIER ASCAT PASS SHOWED WINDS TO 25 KT WITHIN 120 NM NE OF THE CENTER. SEAS AREA ESTIMATED TO BE 8 TO 9 FT WITHIN THIS AREA AND ELSEWHERE WITHIN 75 NM OF THE CENTER. THE LOW WILL WEAKEN FURTHER WITH WINDS AND SEAS DIMINISHING THROUGH THE 24 HOURS AND THE LOW ITSELF DISSIPATING THROUGH THE NEXT 24 TO 36 HOURS. LIGHT TO GENTLE BREEZES REMAIN IN PLACE ACROSS THE REMAINDER OF THE REGION OUTSIDE OF THE TEHUANTEPEC AREA WITH A WEAK PRES GRADIENT IN PLACE. LONG PERIOD NW SWELL WILL MOVE INTO THE REGION WEST OF BAJA CALIFORNIA NORTE TONIGHT...AND REACH AS FAR SOUTH AS 20N THROUGH LATE WED. MEANWHILE A POSSIBLE TROPICAL CYCLONE WILL MOVE INTO THE REGION FROM THE SOUTH...WITH THE ONSET OF ASSOCIATED FRESH WINDS AND SEAS TO 8 FT REACHING SOCORRO ISLAND BY EARLY THU. S OF 15N E OF 120W...FRESH TO STRONG WINDS WILL PULSE THROUGH THE GULF OF PAPAGAYO TONIGHT AND TUE NIGHT. A TIGHT PRES PATTERN BETWEEN HIGH PRES OVER THE U.S. LOWER MISSISSIPPI VALLEY...BEHIND THE AFOREMENTIONED COLD FRONT PASSING THROUGH CHIVELA PASS...AND THE MONSOON TROUGH TO THE S HAS SET UP ACROSS CENTRAL AMERICA. A FRESH TO STRONG E-NE BREEZE IS EXPECTED IN AND DOWNWIND OF THE GULF OF PAPAGAYO WITH THE ASSISTANCE OF NOCTURNAL DRAINAGE FLOW BEFORE SUNRISE. THESE WINDS WILL SHIFT AWAY FROM THE COAST IN THE AFTERNOON AND DIMINISH AT NIGHT BEFORE REPEATING THE PATTERN BEGINNING EARLY TUE MORNING. 7-9 FT SEAS ARE EXPECTED. ELSEWHERE SW SWELL WILL MOVE ACROSS THE EQUATOR AND MIX WITH SHORTER PERIOD NE SWELL EMERGING OUT OF TEHUANTEPEC RESULTING IN SEA OF 8 TO 10 FT FROM ROUGHLY 05N TO 15N BETWEEN 90W AND 100W THROUGH MID WEEK. ELSEWHERE...HIGH PRES OVER THE EASTERN NORTH PACIFIC HAS BEEN COMPROMISED BY TWO COLD FRONTS N OF THE AREA. TRADES HAVE WEAKENED TO A GENTLE TO MODERATE BREEZE ACCORDING TO THE RECENT SCATTEROMETER PASSES. ONE OF THE COLD FRONTS IS FORECAST TO REACH FAR N WATERS OVERNIGHT TUE NIGHT...WITH N-NW WINDS EXPECTED TO REACH 20-25 KT BEHIND THE FRONT OVER FAR NE WATERS BY EARLY WED MORNING. NW SWELL ASSOCIATED WITH THIS SYSTEM WILL PROPAGATE INTO THE AREA AHEAD OF THE FRONT...WITH SEAS IN THE 7- 9 FT RANGE EXPECTED OVER WATERS N OF 26N BETWEEN 118W AND 134W LATE TUE NIGHT INTO WED MORNING. $$ CHRISTENSEN