000 AXPZ20 KNHC 262201 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC WED JAN 26 2011 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... AXIS IS CENTERED ALONG 5N78W 5N90W 5N106W 5N120W 7N130W 7N140W. SCATTERED MODERATE CONVECTION IS WITHIN 30 NM OF THE AXIS BETWEEN 111W-112W. ...DISCUSSION... W OF 115W...A FAIRLY AMPLIFIED UPPER PATTERN REMAINS IN PLACE N OF 20N. AN UPPER TROUGH EXTENDS FROM NORTHERN BAJA SW TO A DEVELOPING CYCLONIC CIRCULATION AT 24N124W...AND CONTINUES SSW TO 15N127W. ANOTHER UPPER TROUGH WITH AN ASSOCIATED COLD FRONT IS DIGGING EASTWARD THROUGH 145W N OF 20N...RESULTING IN A SHARPENING UPPER RIDGE BETWEEN THE TWO TROUGH STRETCHING FROM THE COAST OF WASHINGTON TO NEAR 21N137W. THE ASSOCIATED 1023 MB SURFACE HIGH IS ANALYZED N OF THE AREA AT 31N134W WITH A RIDGE SE TO NEAR 19N114W. THE HIGH IS FORECAST TO SHIFT SW TO NEAR 28N137W BY EARLY THU...BLOCKING THE ADVANCE OF THE COLD FRONT WHICH WILL DISSIPATE NW OF THE AREA THROUGH THU NIGHT AS THE UPPER SUPPORTING TROUGH LIFTS TO THE NE. MEANWHILE...THE SOUTHERN EXTENT OF THE UPPER TROUGH FROM NORTHERN BAJA TO 12N142W BECOMES CUTOFF NEAR 13N145W ON THU. AN ASSOCIATED SURFACE TROUGH CURRENTLY JUST W OF THE AREA ALONG 142W BECOMES MORE PRONOUNCED BY THU AS THE UPPER LOW CUTS OFF. THE SURFACE HIGH PRES DROPS SOUTH AT THE SAME TIME ALLOWING FOR FRESH TO STRONG TRADES BETWEEN THE TROUGH AND THE HIGH PRES...WITH SEAS BUILDING TO AS HIGH AS 13 FT IN MIXED NW AND NE SWELL. MEANWHILE NW SWELL OF 10 FT OR GREATER IS MOVING INTO THE NW PORTION OF THE DISCUSSION AREA...REINFORCING AN EARLY GROUP OF NW SWELL OF 8 TO 9 FT CURRENTLY MOVING ACROSS THE WHOLE AREA. E OF 115W...BROAD SW UPPER LEVEL FLOW AHEAD OF THE ABOVE DESCRIBED TROUGH DOMINATES THIS PART OF THE AREA WITH A MID/UPPER LEVEL TROUGH EMBEDDED WITHIN THIS FLOW ALONG 16N98W TO 12N95W TO 5N88W. ABUNDANT UPPER LEVEL MOSITURE IS BEING ADVECTED BY THIS FLOW NORTHEASTWARD TO ACROSS NORTHERN AND CENTRAL MEXICO. PATCHES OF MODERATE SUBSIDENCE RESULTING IN RELATIVELY CLOUD FREE AREAS ARE NOTED TO THE E OF THE TROUGH...AND W OF THE TROUGH TO NEAR 105W. ONLY ISOLATED WEAK CONVECTION IS NOTED OVER THIS PORTION OF THE AREA MAINLY ALONG AND NEAR THE ITCZ. GAP WINDS... TIGHTENING PRES GRADIENT OVER SOUTHEASTERN MEXICO DUE TO A HIGH CENTER OF 1028 MB OVER NW MEXICO AND THE SOUTHERN EXTENT OF A COLD FRONT DRAPED ACROSS THE YUCATAN PENINSULA HAD PROMPTED A GALE WARNING FOR THE GULF OF TEHUANTEPEC AS A COLD AIR MASS SURGES SWD THROUGH THE CHIVELA PASS AS INDICATED BY SURFACE OBSERVATION REPORTS FROM STATION IXTEPEC ON THE SOUTH SIDE OF THE ISTHMUS WHERE N WINDS OVER THE PAST SEVERAL HOURS HAVE BEEN SUSTAINED AT 30 KT WITH GUSTS TO 40 KT. THE HIGH WILL WEAKEN SOME OVER THE NEXT 24 TO 48 HOURS AS IS SHIFTS ESE ALLOWING FOR THE GALE WINDS TO TEMPORARILY DIMINISH...BUT IS EXPECTED TO BEGIN LATE THU NIGHT AS THE NLY SURGE INTENSIFIES. SEAS IN THE GULF ARE EXPECTED TO BUILD UP POSSIBLY 10 FT. THE STRONG TEHUANTEPEC FLOW WILL GENERATE NE SWELL BY THU THAT WILL MIX WITH AN AREA OF DECAYING NW SWELL GENERALLY S OF 14N BETWEEN 90W AND 111W. NE TO E 20 KT WINDS WILL BEGIN THROUGH THE GULF PAPAGAYO IN ABOUT 12 HOURS AND EXTENT WESTWARD TO 88W FROM 10N TO 12N AND TO 90W BY 24 AND 48 HOURS. GULF OF CALIFORNIA...HIGH PRES BUILDING OVER THE GREAT BASIN WILL IMPART FRESH TO STRONG NW FLOW OVER MAINLY THE NORTHERN GULF OF CALIFORNIA THROUGH FRI. $$ AGUIRRE