000 AXPZ20 KNHC 242204 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC THU DEC 24 2009 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0315 UTC. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 8N79W 6N90W 5N101W 8N112W 8N125W 8N140W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 180 NM S OF THE AXIS BETWEEN 117W-121W. SCATTERED MODERATE CONVECTION IS WITHIN 30 NM EITHER SIDE OF THE AXIS BETWEEN 132W-135W. ...DISCUSSION... A LARGE UPPER LEVEL TROUGH HAS CROSSED IN THE FAR WESTERN PORTION OF THE AREA...AND EXTENDS FROM 30N126W TO 20N129W TO 9N135W TO W OF THE AREA AT 5N140W. AT THE SURFACE ...A COLD FRONT IS ABOUT 290 NM NW OF THE AREA N OF 27N.5 THAT IS JUST ENTERING THE NW PART OF THE AREA FROM NEAR 30N140W TO 21N142W. WIDELY SCATTERED SHOWERS AND ISOLATED WEAK TSTMS ARE JUST NW OF THE AREA AHEAD OF THE FRONT. SURFACE WINDS OVER THE NW PORTION OF THE AREA HAVE RESPONDED TO THE FRONT...AND ARE SE TO S 20 TO 25 KT N OF 25N W OF 135W WITH SEAS 10 TO 15 FT IN A NW SWELL. THE FRONT IS FORECAST TO REACH FROM NEAR 31N138W TO 27N140W IN 24 HRS...AND FROM 30N127W TO 25N133W DISSIPATING TO 20N140W IN 48 HRS WITH NW SWELLS BUILDING UP TO 15 FT BEHIND IT IN 24 HRS...AND UP TO 20 FT IN ABOUT 48 HRS. THE REMAINDER OF THE DISCUSSION AREA E OF THE TROUGH IS UNDER THE DOMINANCE OF RATHER BROAD MID/UPPER LEVEL RIDGING WITH A FAINT RIDGE AXIS EXTENDING FROM 30N118W TO 18N110W TO A MID/UPPER LEVEL ANTICYLONE MOVING ENE NEAR 10N98W. A 1024 MB HIGH CENTER IS N OF THE AREA NEAR 37N127W WITH A RIDGE SW TO 30N132W TO 20N140W. A JET STREAM BRANCH EXTENDS NE FROM 18N132W TO 23N123W WHERE IT MERGES WITH ANOTHER JET BRANCH FROM THE NW. THE MERGED BRANCH THAN MAKES AN EASTWARD TRAJECTORY TOWARDS CENTRAL BAJA CALIFORNIA AND ACROSS NORTHERN MEXICO TO INTO THE WESTERN GULF OF MEXICO. MAXIMUM JET CORE WIND SPEEDS AS NOTED BY SATELLITE DERIVED WIND DATA ARE IN THE RANGE OF 60-100 KT. OVER THE FAR NE PORTION CONFLUENT FLOW PATTERN IS NOTED TO THE NE OF THE MID/UPPER LEVEL RIDGE. A SMALL POCKET OF DRY AIR HAS PUSHED EASTWARD TO OVER FAR NORTHERN BAJA CALIFORNIA AND NORTHERN MEXICO. THE UPPER FLOW AHEAD OF THE TROUGH CONTINUES TO PULL A PLUME OF MOSTLY MID AND UPPER LEVEL MOISTURE DERIVED FROM THE ITCZ CONSISTING OF MOSTLY BROKEN HIGH CLOUDS NE AND E OVER THE AREA FROM 9N TO 19N W OF 120W...AND N OF 12N E OF 120W TO ACROSS BAJA CALIFORNIA AND OVER NORTHERN AND CENTRAL MEXICO...AND AS FAR E AS THE GULF OF MEXICO. SCATTERED TO BROKEN PATCHES OF LOW CLOUDS WITH ISOLATED SHOWERS ARE N OF 19N W OF 125W. ELSEWHERE AT THE SURFACE...A WEAK AND PERSISTENT WEAK 1012 MB LOW MOVING W ABOUT 10 KT IS NEAR 8N128W WITH A TROUGH NNE TO 13N126W. AN AREA OF NE TO E 20 KT TRADE WINDS INDUCED BY A TIGHTENING OF THE PRES GRADIENT BETWEEN SURFACE HIGH PRES TO THE N AND NW OF THE LOW IS LOCATED FROM 15N TO 22N BETWEEN 120W AND 132W. WITH THE LOW WEAKENING FURTHER AND HIGH PRES TO THE N ALSO WEAKENING IN ADVANCE OF A STRONGER COLD FRONT APPROACHING THE FAR NW PORTION OF THE AREA...THESE WINDS WILL DIMINISH CONSIDERABLY THROUGH THE NEXT 24-36 HRS...BUT SEAS UP TO 12 FT IN LARGE NW SWELLS WILL BE POSSIBLE OVER THE FAR W AND NW SECTIONS THROUGH FRI. THE SOUTHERN PORTION OF A RATHER SHARP MID/UPPER LEVEL TROUGH EXTENDS FROM THE FAR WESTERN CARIBBEAN SEA SSW TO ACROSS CENTRAL AMERICA...AND REACHES TO NEAR 4N87W. WIDELY SCATTERED SHOWERS AND TSTMS ARE NEAR THE BASE OF THE TROUGH FROM 4N TO 8N BETWEEN 86W AND 91W. THE UPPER FLOW PATTERN BETWEEN THE TROUGH AND THE WESTERN EXTENSION OF MID/UPPER LEVEL RIDGING THAT EXTENDS OVER S AMERICA ALONG 8N IS ADVECTING UPPER LEVEL ITCZ MOISTURE NORTHWARD ACROSS PANAMA FROM N OF 5N. SATELLITE WATER VAPOR IMAGERY SHOWED ABUNDANT MODERATE SUBSIDENCE INDICATIVE OF DRY SINKING AIR AND VERY STABLE CONDITIONS COVERING JUST ABOUT THE ENTIRE AREA S AND SE OF THE ABOVE MENTIONED PLUME OF CLOUDS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ AGUIRRE 000 AXPZ20 KNHC 242204 RRA TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC THU DEC 24 2009 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2145 UTC. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 8N79W 6N90W 5N101W 8N112W 8N125W 8N140W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 180 NM S OF THE AXIS BETWEEN 117W-121W. SCATTERED MODERATE CONVECTION IS WITHIN 30 NM EITHER SIDE OF THE AXIS BETWEEN 132W-135W. ...DISCUSSION... A LARGE UPPER LEVEL TROUGH HAS CROSSED IN THE FAR WESTERN PORTION OF THE AREA...AND EXTENDS FROM 30N126W TO 20N129W TO 9N135W TO W OF THE AREA AT 5N140W. AT THE SURFACE ...A COLD FRONT IS ABOUT 290 NM NW OF THE AREA N OF 27N.5 THAT IS JUST ENTERING THE NW PART OF THE AREA FROM NEAR 30N140W TO 21N142W. WIDELY SCATTERED SHOWERS AND ISOLATED WEAK TSTMS ARE JUST NW OF THE AREA AHEAD OF THE FRONT. SURFACE WINDS OVER THE NW PORTION OF THE AREA HAVE RESPONDED TO THE FRONT...AND ARE SE TO S 20 TO 25 KT N OF 25N W OF 135W WITH SEAS 10 TO 15 FT IN A NW SWELL. THE FRONT IS FORECAST TO REACH FROM NEAR 31N138W TO 27N140W IN 24 HRS...AND FROM 30N127W TO 25N133W DISSIPATING TO 20N140W IN 48 HRS WITH NW SWELLS BUILDING UP TO 15 FT BEHIND IT IN 24 HRS...AND UP TO 20 FT IN ABOUT 48 HRS. THE REMAINDER OF THE DISCUSSION AREA E OF THE TROUGH IS UNDER THE DOMINANCE OF RATHER BROAD MID/UPPER LEVEL RIDGING WITH A FAINT RIDGE AXIS EXTENDING FROM 30N118W TO 18N110W TO A MID/UPPER LEVEL ANTICYLONE MOVING ENE NEAR 10N98W. A 1024 MB HIGH CENTER IS N OF THE AREA NEAR 37N127W WITH A RIDGE SW TO 30N132W TO 20N140W. A JET STREAM BRANCH EXTENDS NE FROM 18N132W TO 23N123W WHERE IT MERGES WITH ANOTHER JET BRANCH FROM THE NW. THE MERGED BRANCH THAN MAKES AN EASTWARD TRAJECTORY TOWARDS CENTRAL BAJA CALIFORNIA AND ACROSS NORTHERN MEXICO TO INTO THE WESTERN GULF OF MEXICO. MAXIMUM JET CORE WIND SPEEDS AS NOTED BY SATELLITE DERIVED WIND DATA ARE IN THE RANGE OF 60-100 KT. OVER THE FAR NE PORTION CONFLUENT FLOW PATTERN IS NOTED TO THE NE OF THE MID/UPPER LEVEL RIDGE. A SMALL POCKET OF DRY AIR HAS PUSHED EASTWARD TO OVER FAR NORTHERN BAJA CALIFORNIA AND NORTHERN MEXICO. THE UPPER FLOW AHEAD OF THE TROUGH CONTINUES TO PULL A PLUME OF MOSTLY MID AND UPPER LEVEL MOISTURE DERIVED FROM THE ITCZ CONSISTING OF MOSTLY BROKEN HIGH CLOUDS NE AND E OVER THE AREA FROM 9N TO 19N W OF 120W...AND N OF 12N E OF 120W TO ACROSS BAJA CALIFORNIA AND OVER NORTHERN AND CENTRAL MEXICO...AND AS FAR E AS THE GULF OF MEXICO. SCATTERED TO BROKEN PATCHES OF LOW CLOUDS WITH ISOLATED SHOWERS ARE N OF 19N W OF 125W. ELSEWHERE AT THE SURFACE...A WEAK AND PERSISTENT WEAK 1012 MB LOW MOVING W ABOUT 10 KT IS NEAR 8N128W WITH A TROUGH NNE TO 13N126W. AN AREA OF NE TO E 20 KT TRADE WINDS INDUCED BY A TIGHTENING OF THE PRES GRADIENT BETWEEN SURFACE HIGH PRES TO THE N AND NW OF THE LOW IS LOCATED FROM 15N TO 22N BETWEEN 120W AND 132W. WITH THE LOW WEAKENING FURTHER AND HIGH PRES TO THE N ALSO WEAKENING IN ADVANCE OF A STRONGER COLD FRONT APPROACHING THE FAR NW PORTION OF THE AREA...THESE WINDS WILL DIMINISH CONSIDERABLY THROUGH THE NEXT 24-36 HRS...BUT SEAS UP TO 12 FT IN LARGE NW SWELLS WILL BE POSSIBLE OVER THE FAR W AND NW SECTIONS THROUGH FRI. THE SOUTHERN PORTION OF A RATHER SHARP MID/UPPER LEVEL TROUGH EXTENDS FROM THE FAR WESTERN CARIBBEAN SEA SSW TO ACROSS CENTRAL AMERICA...AND REACHES TO NEAR 4N87W. WIDELY SCATTERED SHOWERS AND TSTMS ARE NEAR THE BASE OF THE TROUGH FROM 4N TO 8N BETWEEN 86W AND 91W. THE UPPER FLOW PATTERN BETWEEN THE TROUGH AND THE WESTERN EXTENSION OF MID/UPPER LEVEL RIDGING THAT EXTENDS OVER S AMERICA ALONG 8N IS ADVECTING UPPER LEVEL ITCZ MOISTURE NORTHWARD ACROSS PANAMA FROM N OF 5N. SATELLITE WATER VAPOR IMAGERY SHOWED ABUNDANT MODERATE SUBSIDENCE INDICATIVE OF DRY SINKING AIR AND VERY STABLE CONDITIONS COVERING JUST ABOUT THE ENTIRE AREA S AND SE OF THE ABOVE MENTIONED PLUME OF CLOUDS. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ AGUIRRE