000 AXPZ20 KNHC 042202 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC TUE DEC 04 2012 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 2145 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM 07N78W TO 05N86W TO 07N98W WHERE LOW LEVEL WINDS SUGGEST IT TRANSITIONS TO THE ITCZ TO 07N123W TO 06N133W TO 07N140W. SCATTERED MODERATE CONVECTION EXISTS FROM 10N TO 12N BETWEEN 118W-123W. ...DISCUSSION... ...HIGHLY AMPLIFIED FEATURES ACROSS THE REGION... AN ANTICYCLONE MOVING SE IS CENTERED AT 26N117W WITH A RIDGE EXTENDING NNE TO A CREST OVER THE WESTERN U.S. WITH THE ANTICYCLONE MOVING SE...THIS WILL FOR A SHORTWAVE OVER THE NW PORTION OF THE AREA TO ALSO MOVE E BUT WILL DAMPEN OUT WITHIN THE NEXT 24 HRS. THE FAR SRN END OF A SHORTWAVE TROUGH IS SE OF THE ANTICYCLONE MOVING SLIDING EWD ACROSS CENTRAL MEXICO. TO THE SW OF THE ANTICYCLONE...A SHARPENING UPPER LEVEL TROUGH IS EVIDENT ROUGHLY ALONG 127W FROM 09N TO A CUT-OFF LOW AT 19N127W. THE TROUGH EXTENDS SSE FROM THE LOW TO NEAR THE EQUATOR AT 124W. AS THE TROUGH SHARPENS FURTHER WITH TIME THE LOW CONTINUE TO RESPOND BY LIFTING NWD ALLOWING FOR AN AREA OF EXTENSIVE UPPER LEVEL RIDGING TO ITS E AND SE TO EXPAND TO THE N. ANOTHER EXPANSIVE AREA OF UPPER LEVEL RIDGING IS TO THE SW OF THE SHARP TROUGH...AND IS SLOWLY EDGING EWD AS THE LOW LIFTS N. SATELLITE-DERIVED WINDS INDICATE THAT A SWLY DIFFLUENT PATTERN ALOFT IS PRESENT TO THE E OF THE TROUGH...AND HELPING TO SUSTAIN THE AN AREA OF INCREASED MULTILAYERED CLOUDINESS ALONG AND NEAR THE ITCZ AXIS FROM ABOUT 05N TO 15N AND BETWEEN 116W AND 126W. THE CONVECTION DESCRIBED ABOVE IN RELATION TO THE ITCZ ABOVE IS EMBEDDED WITHIN THIS AREA OF CLOUDINESS. HIGH LEVEL DEBRIS CLOUDS FROM THE INCREASED AREA OF MULTILAYERED CLOUDINESS ARE STREAMING NNE TO NEAR 20N BETWEEN 117W AND 125W...AND THEN EWD TO ACROSS CENTRAL MEXICO FROM 17N TO 24N. ELSEWHERE SATELLITE WATER VAPOR IMAGERY SHOWS MOSTLY MODERATE SUBSIDENCE MAINTAIN A RATHER STABLE ATMOSPHERE WITH DRY AND STABLE CONDITIONS AT THE SURFACE/LOWER LEVELS. AT THE SURFACE...A 1025 MB HIGH CENTER IS ANALYZED AT 28N126W WITH A RIDGE SW TO W OF THE AREA AT 23N140W. PATCHES OF STRATOCUMULUS CLOUDS MOVING WSW WITH ISOLATED SHOWERS ARE SEEN N OF 12N AND W OF 115W. ONLY MINIMAL DYNAMIC LIFT IS BEING GENERATED BY THE PRESENCE OF THE MONSOON TROUGH AXIS AS STATED ABOVE. WIDELY SCATTERED SHOWERS AND ISOLATED WEAK TSTMS ARE OCCURRING WITHIN 120 NM EITHER SIDE OF THE MONSOON TROUGH AXIS AT THIS TIME. IN REFERENCE TO THE MARINE ASPECT OF THE AREA....WINDS AND SEAS REMAIN BELOW ADVISORY CRITERIA WITH THE EXCEPTION OF 8 FT SEAS IN NW SWELL N OF 26N BETWEEN 115W AND 117W OFF THE COAST OF THE BAJA CALIFORNIA PENINSULA. GAP WINDS... A COLD FRONT IS EXPECTED TO MOVE INTO THE GULF OF MEXICO EARLY WEDNESDAY FOLLOWED BY A COOLER AND STABLE AIR MASS. THIS AIR MASS IS FORECAST TO SURGE ALONG THE GULF COAST OF MEXICO...AND THROUGH THE CHIVELA PASS TO EVENTUALLY THE GULF OF TEHUANTEPEC. BASED ON GLOBAL MODEL GUIDANCE...WINDS ARE EXPECTED TO REACH 30 KT BY WEDNESDAY MORNING WITH SEAS BUILDING TO A 10 FT MAX LATE WED AND THROUGH THURSDAY. WHILE GFS AND ECMWF GUIDANCE SUGGEST WINDS WILL REMAIN BELOW GALE FORCE...THE NAM HINTS AT WINDS EXCEEDING GALE FORCE VERY BRIEFLY IN THE MORNING HOURS ON THURSDAY WITH MAXIMUM DRAINAGE FLOW PEAKING AROUND 06/1200 UTC. WITH LOW CONFIDENCE THINKING OF AN OCCURRENCE OF GALE FORCE WINDS...WILL MAINTAIN STATUS QUO WITH PREVIOUS FORECAST THINKING AND HOLD WINDS AT A MAXIMUM OF 30 KT AND UPDATE FORECAST WINDS IN THE NEAR FUTURE IF MODEL TRENDS COME INTO A CONSENSUS WITH SHOWING GALE FORCE WINDS. WINDS WILL CONTINUE TO PULSE IN THE GULF OF PAPAGAYO TO 20 KT DURING LATE NIGHT AND EARLY MORNING HOURS THEN DIMINISH BELOW 15 KT IN THE AFTERNOON THROUGH FRI. $$ AGUIRRE