000 AXPZ20 KNHC 082202 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC SAT DEC 08 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 W FROM THE NW COAST OF COLOMBIA ACROSS THE PANAMA/COSTA RICA BORDER TO 07N88W...THEN TURNS SW THROUGH AN EMBEDDED 1009 MB LOW PRESSURE CENTER AT 08N95W WHERE LOW LEVEL WINDS INDICATE A TRANSITION TO AN ITCZ AXIS THAT EXTENDS TO 07N101W TO 10N110W TO 10N123W TO 07N140W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 120 NM S OF THE AXIS W OF 133W. ...DISCUSSION... ALOFT...A PERSISTENT LONGWAVE UPPER RIDGE IS W OF THE AREA WITH ITS MEAN AXIS ANCHORED ALONG 150W WHILE A LONGWAVE TROUGH OVER CENTRAL U.S. EXTENDS SW TO NEAR 29N126W. SATELLITE WATER VAPOR IMAGERY SHOWS A SHORTWAVE TROUGH SWINGING SEWD THROUGH THE BASE OF THE LONGWAVE TROUGH FROM 32N123W TO 27N131W AND INTO A MID/UPPER CYCLONE DROPPING S AT 27N140W WHICH OCCASIONALLY INDUCES A SURFACE TROUGH OVER THE FAR NW WATERS. ANOTHER SHORTWAVE TROUGH EXTENDS FROM 32N112W SW TO 18N120W...THEN TURNS SEWD TO 14N118W TO 09N110W TO NEAR 02N106W. BETWEEN THIS TROUGH AND THE MID/UPPER CYCLONE...A SHORTWAVE RIDGE SLIDING EWD IS JUST S OF FIRST SHORTWAVE TROUGH ROUGHLY ALONG 27N123W 16N128W. DENSE UPPER MOISTURE...IN THE FORM OF BROKEN CIRRUS CLOUDS...IS NOTED UNDER THIS RIDGE...WITHIN 200 NM EITHER SIDE OF THE RIDGE. THESE CLOUDS SPREAD AS FAR NE AS 28N121W WHERE SW-W FLOW S OF THE FIRST SHORTWAVE TROUGH STEERS THEM TOWARDS NRN BAJA CALIFORNIA AND OVER FAR NW MEXICO. TO THE SE OF THE SHORTWAVE TROUGH ALONG 32N112W 18N120W...BROAD MID/UPPER LEVEL RIDGING COVERS THE AREA WITH A MEAN AXIS EXTENDING NW TO SE FROM 26N115W TO 18N104W. THIS PATTERN SETS UP AN AREA OF UPPER DIFFLUENCE SUPPORTING ENHANCED BROKEN TO OVERCAST MULTILAYERED CLOUDS WITH SCATTERED SHOWERS AND ISOLATED TSTMS FROM 11N TO 26N E OF 116W. THE RESULTANT DEBRIS MOISTURE CONTINUES TO BE ADVECTED NNE ALONG THE W PERIPHERY OF THE UPPER RIDGE...WITHIN 240 NM OF A LINE FROM 11N114W TO 26N114W. THIS MOISTURE PLUME THEN TURNS E-NE ACROSS THE UPPER RIDGE AXIS... THINNING SOMEWHAT AS IT CONTINUES NEWD TO THE S AND SE OF THE LONGWAVE TROUGH AXIS...AND WELL W OF THE AREA OVER NW AND N CENTRAL GULF OF MEXICO AND THE SE CONUS. WATER VAPOR IMAGERY CONTINUES TO SHOW VERY DRY AND STABLE ATMOSPHERIC CONDITIONS OVER THE SE PART OF THE AREA WITHIN THE MID/UPPER LEVEL RIDGING. THESE DRY AND STABLE CONDITIONS ARE SUPPRESSING CONVECTION EXCEPT ISOLATED SHOWERS WITHIN 60-75 NM OF THE MONSOON TROUGH LOW AT 08N95W. AT THE LOW LEVELS...A 1029 MB HIGH CENTER N OF THE AREA AT 39N134W EXTENDS A RIDGE SEWD THROUGH 32N130W TO NEAR 22N115W. NLY WINDS OF 15-20 KT ARE NOTED TO THE NE OF THE RIDGE...N OF ABOUT 27N BETWEEN 120W AND 131W...WITH SEAS 8-10 FT IN MIXED NE AND NW SWELL. THESE WINDS ARE EXPECTED TO CHANGE LITTLE OVER THE NEXT 48 HRS. THE TRADES SW OF THE RIDGE ARE AT 15-20 KT IN THE AREA FROM 08-22N W OF 127W...WITH SEAS 7-9 FT IN PRIMARILY IN MIXING NE AND NW SWELL. THE GRADIENT IS EXPECTED TO TIGHTEN ON SUN WITH NE 15-20 KT WINDS COVERING THE WATERS NW OF LINE FROM 32N120W TO 11N140W WITH SEAS 7-9 FT IN MOSTLY IN A NE SWELL. EXPECT NW WINDS AT 5-10 KT WITH SEAS 3-5 FT ALONG THE W COAST OF THE BAJA CALIFORNIA THROUGH SUN MORNING. A COLD FRONT WILL SWEEP S INTO THE EXTREME NE WATERS...INCLUDING THE GULF OF CALIFORNIA ON SUN AFTERNOON. THIS WILL RESULT IN WINDS BECOMING NE 15-20 KT ALONG THE W COAST OF THE BAJA PENINSULA LATE SUN NIGHT INTO MON. LIGHT AND VARIABLE WINDS OVER THE NORTHERN GULF OF CALIFORNIA TODAY WILL BECOME NW BEHIND THE FRONT...INCREASING TO 20-25 KT IN THE NORTHERN GULF WATERS...BRIEFLY 25-30 KT LATE SUN NIGHT...WITH NW WINDS AT 15-25 KT SPREADING S ACROSS THE ENTIRE GULF BY MON NIGHT. EXPECT SEAS MAY BUILD TO AROUND 8 FT BRIEFLY IN THE NRN GULF WATERS MON IN THE AREAS OF LONG NW FETCH...AND 4-6 FT SOUTHERN GULF WATERS BY LATE MON NIGHT. THESE NW WINDS SHOULD DIMINISH TO 10-15 KT TUE NIGHT. GAP WINDS... GULF OF TEHUANTEPEC...A COLD FRONT WILL ENTER THE NW GULF OF MEXICO SUN NIGHT. THE ASSOCIATED NLY WINDS WILL SURGE AT 15-20 KT THROUGH THE CHIVELA PASS TUE AFTERNOON...WITH WINDS GRADUALLY INCREASING TUE NIGHT AND EARLY WED...REACHING NEAR GALE FORCE BY LATE WED...AND CONTINUING INTO MIDDAY THU. NOTE THAT LATEST MODEL GUIDANCE IS NOT AS AGGRESSIVE AS PREVIOUS RUNS. GULF OF PAPAGAYO...A COUPLE OF SHIPS "3FQ04" AT 11N86W AND "9V7955" AT 10N88W REPORTED NE WINDS OF 20-25 KT JUST A FEW HOURS. THESE WIND SPEEDS ARE HIGHER THAN WHAT MODEL GUIDANCE SUGGESTS. THE ASCAT PASS FROM 1540 UTC THIS MORNING INDICATED NE WINDS OF 15-20 KT FROM 10N TO 11N JUST E OF THESE SHIPS TO THE GULF OF PAPAGAYO. BASED ON THIS OBSERVATIONS WILL INTRODUCE A BRIEF PERIOD OF NE 20-25 KT WINDS FOR GULF OF PAPAGAYO AND VICINITY THROUGH AT LEAST THE NEXT 24 HRS. AFTER THIS TIME...NE-E WINDS WILL CONTINUE TO PULSE AT 10-15 KT IN AND DOWNSTREAM OF THE GULF OF PAPAGAYO THROUGH THE MIDDLE OF NEXT WEEK...WITH GUIDANCE SUGGESTING AN INCREASE TO 20-25 KT BEGINNING ON WED NIGHT. $$ AGUIRRE