000 AXPZ20 KNHC 270318 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC SAT SEP 27 2008 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 0230 UTC. ...TROPICAL WAVES... TROPICAL WAVE ALONG 90W N OF 5N TO ACROSS EASTERN GUATEMALA IS ESTIMATED TO BE MOVING W 13 KT. NO DEEP CONVECTION IS NOTED WITH THIS WAVE...EXCEPT ALONG THE COAST OF SOUTHERN GUATEMALA WHERE CLUSTERS OF SCATTERED STRONG CONVECTION ARE NOTED. GLOBAL MODELS STILL SUGGEST THAT LOW PRES MAY DEVELOP ALONG OF NEAR THIS WAVE OVER THE NEXT FEW DAYS. TROPICAL WAVE ALONG 100W N OF 5N IS MOVING W 10 KT. THIS WAVE HAS LOST A LOT OF ITS ASSOCIATED CLOUDINESS AND CONVECTION OBSERVED DURING THE PAST FEW DAYS AS THE PERSISTENT MONSOON FLOW PATTERN HAS DIMINISHED OVER THE FAR EASTERN PORTION OF THE AREA. A TROPICAL WAVE IS CURRENTLY E OF THE AREA OVER WESTERN COLOMBIA ALONG 76W MOVING W 10-15 KT...AND IS EXPECTED TO ENTER THE FAR EASTERN PART OF THE AREA WITHIN THE NEXT 12 HOURS. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 11N86W 12N92W 12N100W 12N110W 12N120W 11N130W 9N140W. SCATTERED STRONG CONVECTION IS WITHIN 120 NM S OF THE AXIS BETWEEN 112W-115W...AND ALSO N OF THE AXIS WITHIN 60 NM OF LINE 12N135W TO 12N138W. SCATTERED MODERATE CONVECTION IS WITHIN 30 NM EITHER SIDE OF THE AXIS BETWEEN 115W-119W...AND ALSO WITHIN 60 NM S OF THE AXIS BETWEEN 121W-123W. ...DISCUSSION... W OF 120W... THE WESTERN EXTENSION OF THE MID/UPPER LEVEL RIDGE MENTIONED BELOW UNDER E OF 120W EXTENDS SW TO 15N134W WHERE A COL REGION IS OBSERVED ON WATER VAPOR IMAGERY. THIS REGION DEFINES THE POINT WHERE A MID/UPPER LEVEL TROUGH STRETCHES THROUGH 19N135W TO 27N135W TO N OF THE AREA AT 32N136W. TO THE W OF THE TROUGH ...BROAD MID/UPPER LEVEL RIDGING IS PRESENT...AND IS ASSOCIATED WITH A VERY PRONOUNCED UPPER LEVEL ANTICYCLONE W OF THE AREA NEAR 14N146W. THE TROUGH IS FORECAST TO MOVE ACROSS THE NORTHERN PORTION OF THE AREA THROUGH SUN BEFORE LIFTING NE WHILE FOLLOWED BY STRONG NW FLOW SUN INTO MON. MOISTURE IN THIS AREA REMAINS VERY LIMITED AS MODERATE TO STRONG SUBSIDENCE PREVAILS. ONLY DEEP MOISTURE IS THAT DIRECTLY ASSOCIATED WITH THE ITCZ. AT THE SURFACE...A HIGH CENTER OF 1019 MB IS JUST NW OF THE AREA NEAR 31N142W WITH A RIDGE SE TO 27N134W TO 22N124W. HIGH PRES COVERS THE AREA GENERALLY N OF 22N. A WEAK 1010 MB LOW IS JUST N OF THE ITCZ NEAR 11N134W 1010 MB...AND IS ENHANCING CONVECTION ALONG THE ITCZ IN ITS VICINITY. IN REFERENCE TO THE HIGH SEAS MARINE FORECAST...S SWELLS OF UP TO 8 FT WILL IMPACT THE AREA S OF ABOUT 5N BETWEEN 93W-105W... AND ALSO FROM 5N-10N BETWEEN 110W-125W. THESE SEAS ARE FORECAST TO BUILD UP TO 9 FT PER WAVEWATCH GUIDANCE IN 48 HOURS OVER THE AREA S OF 5N BETWEEN 82W-100W...AND BETWEEN 100W-115W. E OF 120W... MID/UPPER LEVEL ANTICYCLONE IS CENTERED JUST SW OF THE BAJA CALIFORNIA PENINSULA NEAR 21N112W WITH A RIDGE EXTENDING SW THROUGH 18N120W. MODERATE TO STRONG SUBSIDENCE AND ASSOCIATED DRY STABLE AIR IS EVIDENT ON WATER VAPOR IMAGERY TO THE N OF THE ANTICYCLONE. MODERATE TO STRONG UPPER ELY WINDS ARE NOTED OVER THE SW PERIPHERY OF THE RIDGE. WEAK SURFACE LOW PRES OF 1009 MB NEAR 16N116W IS DRIFTING W. MODERATE TO STRONG UPPER LEVEL ELY WINDS ARE ADVECTING DEBRIS MOISTURE WESTWARD WITHIN THE AREA FROM 8N-19N AND W OF 100W. A WEAK SURFACE PRES PATTERN HOLDS THROUGHOUT OVER THE NEXT FEW DAYS...EXCEPT FOR THE GULF OF TEHUANTEPEC WHERE NLY FLOW WILL DRAIN DOWN FROM THE WESTERN GULF OF MEXICO TO PRODUCE N WINDS OF 20-25 KT EXPECTED TO BEGIN SHORTLY. THIS EVENT IS FORECAST TO LAST WELL INTO NEXT WEEK. $$ AGUIRRE