000 AXPZ20 KNHC 070950 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC MON NOV 07 2011 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0645 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS SW ACROSS CENTRAL COSTA RICA TO THE E PACIFIC AT 06N93W WHERE LOW LEVEL WINDS INDICATE A TRANSITION TO AN ITCZ. THE ITCZ AXIS THEN EXTENDS NW TO 12N110W...RESUMES FROM 12N112W TO 10N127W...AND RESUMES FROM 08N130W TO BEYOND 07N140W. TWO LOW LEVEL TROUGHS...ORIENTATED NE TO SW...INTERRUPT THE ITCZ. THE FIRST TROUGH EXTENDS FROM 12N112W TO 16N109W ACCOMPANIED BY SCATTERED MODERATE ISOLATED STRONG CONVECTION WITHIN 60 NM OF TROUGH AXIS. THE SECOND TROUGH EXTENDS FROM 10N127W TO 14N124W...AND IS ACCOMPANIED BY SCATTERED MODERATE ISOLATED STRONG CONVECTION WITHIN 90 NM OF TROUGH AXIS. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS ALSO NOTED S OF PANAMA WITHIN 45 NM 07N79W...AND ALONG 09N BETWEEN 115W AND 120W. ...DISCUSSION... A LONG WAVE TROUGH DOMINATES WESTERN N AMERICA WITH ITS MEAN AXIS CONTINUING SW INTO THE DISCUSSION AREA FROM 32N115W TO A BASE AT 12N120W. TWO AREAS OF UPPER MOISTURE ARE ROTATING THROUGH THE UPPER PATTERN WITH THE EASTERN MOST AREA COVERING ARIZONA AND NEW MEXICO...BUT SEEMS TO BE EVAPORATING WITH TIME. A SECOND AREA OF MOISTURE IS W OF THE UPPER TROUGH AXIS...AND IS SHIFTING SE OVER THE DISCUSSION AREA TO THE N OF 28N BETWEEN 122W AND 130W. IMMEDIATELY TO THE S IS A BAND OF VERY DRY UPPER AIR...ROUGHLY WITHIN 120 NM EITHER SIDE OF A LINE FROM 32N136W TO 25N122W WHERE IT TURNS NE ACROSS THE NORTHERN BAJA CALIFORNIA PENINSULA AND THE GULF OF CALIFORNIA. AN UPPER LEVEL CYCLONE CONTINUES OVER THE DEEP TROPICS NEAR 04N107W AND SEPARATES THE UPPER ANTICYCLONIC FLOW. TO THE W AN UPPER ANTICYLONE IS CENTERED NEAR 02S145W WITH A SHORT WAVE RIDGE EXTENDING N TO A CREST NEAR 25N135W. AN UPPER ANTICYCLONE IS CENTERED NEAR 13N94W WITH A RIDGE AMPLIFYING N ACROSS THE CENTRAL GULF OF MEXICO. UPPER DIFFLUENCE IS ENHANCING THE PREVIOUSLY DESCRIBED CONVECTION ALONG THE TWO LOW LEVEL TROUGHS. THE RESULTANT DEBRIS MOISTURE IS ADVECTED NE MERGING WITH A DENSE TROPICAL PLUME THAT ORIGINATES IN THE CENTRAL PACIFIC. THE DENSE PLUME IS WITHIN 240 NM OF LINE 19N140W TO 17N119W... THEN CONTINUES NE ACROSS CENTRAL OLD MEXICO TO OVER THE W CENTRAL GULF OF MEXICO. DEBRIS MOISTURE FROM THE CONVECTION S OF PANAMA EVAPORATES IN THE DRY UPPER AIR THAT DOMINATES THE TROPICS S OF 17N E OF 105W. AT THE LOW LEVELS A RIDGE EXTENDS FROM 32N140W TO 15N110W. A COLD FRONT IS NE OF THE RIDGE FROM 30N116W TO 25N127W TO 29N140W AND ACCOMPANIED BY NORTHERLY WINDS AT 15 TO 20 KT AND COMBINED SEAS TO 10 FT IN NW SWELL. THESE NORTHERLY WINDS SHOULD SPREAD SE TO ALONG THE WESTERN BAJA CALIFORNIA PENINSULA THROUGH TUE. S OF THE RIDGE NE TO E TRADE WINDS CONTINUE AT 15 TO 20 KT WITH SEAS 9 TO 11 FT PRIMARILY IN MIXED NE AND NW SWELL. ALTHOUGH WINDS ARE LIGHT...MIXED N SWELL CONTINUES TO PROPAGATE SE OVER THE REMAINDER OF THE AREA NW OF LINE FROM 23N110W TO 07N130W TO 07N140W...RESULTING IN COMBINED SEAS OF 8 TO 11 FT PRIMARILY IN THE MIXED N SWELL. SOUTHERLY SWELL..WITH SEAS TO 8 FT...IS NOTED OVER THE AREA S OF 08N BETWEEN 95W AND 115W. THIS SOUTHERLY SWELL WILL SPREAD A LITTLE FURTHER N OVER THE NEXT FEW DAYS MIXING WITH THE REINFORCED N SWELL BEHIND THE COLD FRONT. GULF OF CALIFORNIA...SW WINDS ARE INCREASING TO 15 TO 20 KT OVER THE NORTHERN WATERS AHEAD OF THE COLD FRONT. NORTHERLY WINDS AT 15 TO 20 KT ARE FORECAST TO PERSIST THROUGH TUE OVER THE GULF WATERS TO S OF 29N IN THE WAKE OF THE COLD FRONT. NW WINDS WILL THEN INCREASE TO 20 TO 30 KT WED INTO THU. GULF OF TEHUANTEPEC...A STRONG COLD FRONT IS EXPECTED TO MOVE THROUGH THE GULF OF MEXICO WED. NORTHERLY WINDS AT 15 TO 20 KT WILL SURGE INTO THE GULF OF TEHUANTEPEC AS EARLY AS LATE WED POSSIBLY INCREASING TO GALE FORCE AROUND SUNRISE THU. $$ NELSON