000 AXPZ20 KNHC 310301 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC THU MAR 31 2011 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... INTERTROPICAL CONVERGENCE ZONE AXIS IS CENTERED ALONG 5N90W 3N101W 4N113W 4N122W 2N140W. SCATTERED MODERATE CONVECTION IS WITHIN 60 NM S OF THE AXIS BETWEEN 121W-123W AND 126W-129W. ...DISCUSSION... AN UPPER LEVEL TROUGH EXTENDS FROM FAR NORTHEASTERN MEXICO SW ACROSS CENTRAL BAJA CALIFORNIA AND NW TO A COL REGION AT 27N125W. TO THE W OF THE COL THE FLOW BECOMES CYCLONIC GENERALLY N OF 21N W OF 136W IN RESPONSE TO A LARGE UPPER LEVEL CYCLONIC CIRCULATION JUST W OF THE REGION NEAR 26N142W. MODERATE SUBSIDENCE IS NOTED N OF THE TROUGH AND N AND NW OF THE COL REGION. THE UPPER FLOW IS NLY TO THE N OF THE TROUGH E OF THE COL THEN BECOMES NE TO E W OF THE COL TO 136W WHERE IT VEERS TO E TO SE ON THE NORTHERN PERIPHERY OF THE CYCLONIC CIRCULATION. A VERY LARGE ANTICYCLONE IS SITUATED WELL N OF THE REGION NEAR 36N125W WITH A CREST STRETCHING WELL TO THE NW OF THE REGION. QUITE AN IMPRESSIVE AMOUNT OF HIGH LEVEL MOISTURE IS RIDING UP AND OVER THE CREST OF THE RIDGE...THEN DIVING SOUTHEASTWARD TO ACROSS THE WESTERN PORTION OF THE U.S. AND TURNING TO THE SW OFF FAR SOUTHERN CALIFORNIA AND EXTREME NORTHERN BAJA CALIFORNIA. S OF THE UPPER TROUGH BROAD W TO W FLOW COVERS THE AREA E OF 120W...WHILE TO THE W OF 120W THE FLOW BECOMES ANTICYCLONIC AHEAD OF A TROUGH THAT EXTENDS SW FROM THE CYCLONIC CIRCULATION SW TO WELL W OF THE AREA...AND ALSO DUE TO MID/UPPER RIDGE MOVING E ALONG 127W. A JET STREAM BRANCH ENTERS THE REGION THROUGH 21N140W...AND EXTENDS NE TO OVER THE NORTHERN PERIPHERY OF THE RIDGE NEAR 26N129W...THEN HAS A TRAJECTORY TOWARDS THE SE THROUGH 23N120W TO 22N114W AND BRANCHES NE TO ACROSS EXTREME FAR SOUTHERN BAJA CALIFORNIA AND NE TO ACROSS CENTRAL MEXICO. UPPER AIR DATA INDICATES MAXIMUM WINDS IN THE RANGE OF 50-60 KT WITHIN ABOUT 500 NM S OF THE JET. THESE WINDS ARE ADVECTING UPPER LEVEL MOISTURE IN THE FORM OF MOSTLY BROKEN HIGH CIRRUS CLOUDS FROM THE DEEP TROPICS OF THE CENTRAL PACIFIC NORTHEASTWARD TO ACROSS THE FAR EASTERN PORTION OF THE AREA S OF THE UPPER TROUGH FROM 18N-21N. MOSTLY OVERCAST HIGH CIRRUS CLOUDS ARE CONFINED FROM 17N TO 27N W OF 131W AROUND THE EASTERN PERIPHERY OF THE UPPER LEVEL LOW. OVER THE FAR SOUTHERN PORTION OF THE AREA...THE MID/UPPER LEVEL ANTICYCLONE THAT YESTERDAY WAS NOTED OVER THE GALAPAGOS HAS SINCE SHIFTED TO JUST SW OF NICARAGUA WITH A RIDGE SW TO 8N107W. MODERATE SUBSIDENCE AS NOTED IN WATER VAPOR IMAGERY CONTINUES TO MAINTAIN GENERALLY STABLE ATMOSPHERIC CONDITIONS ALLOWING FOR VERY LIMITED TO NO MOISTURE TO BE PRESENT OVER THE PORTION OF THIS AREA S OF 16N AND E OF 101W. UPPER LEVEL MOISTURE...IN THE FORM OF SCATTERED TO BROKEN CIRRUS CLOUDS...IS BEING CHANNELED NORTHEASTWARD ON THE NW PERIPHERY OF THE RIDGE AND TO THE E OF AN UPPER TROUGH THAT EXTENDS FROM 11N114W TO 1N107W TOWARDS SE MEXICO AND THE GULF OF TEHUANTEPEC. AT THE SURFACE...A 1036 MB HIGH CENTER IS LOCATED NW OF THE AREA NEAR 35N136W WITH A RIDGE SE TO 24N125W TO NEAR 21N113W. HIGH PRES COVERS THE DISCUSSION AREA N OF 14N AND W OF 116W. FRESH NE TRADE WINDS ARE PRESENT S OF THE RIDGE AXIS N OF 5N W OF 128W. THIS AREA OF TRADE WINDS IS FORECAST TO DIMINISH IN AREAL COVERAGE IN 24 HOURS...THEN TO LESS THAN 20 KT IN 48 HOURS AS THE GRADIENT BREAKS DOWN. A TIGHT PRES GRADIENT BETWEEN THE 1032 MB HIGH AND LOWER PRES ALONG CALIFORNIA AND BAJA CALIFORNIA IS INDUCING N-NE 20 KT WINDS N OF 27N BETWEEN 120W-125W WHERE COMBINED SEAS ARE UP TO 11 FT IN A NW SWELL. AS THE HIGH RETREATS NW...THE AREA OF N-NE WINDS WILL SHIFT WESTWARD TO N OF 28N BETWEEN 126W-130W IN ABOUT 24 HOURS...THEN DIMINISH TO LESS THAN 20 KT IN ABOUT 30 HOURS AS THE GRADIENT RELAXES. SEAS IN THE RANGE OF 9-11 FT IN LONG PERIOD NW SWELLS WILL PLAGUE MOST OF THE NW SECTION OF THE REGION BEGINNING IN 30 HOURS AND SPREADING FURTHER SE THROUGH 48 HOURS. A WEAK SURFACE TROUGH IS ALONG 120W/121W S OF 8N MOVING W AT 10 KT...AND WAS ENHANCING CONVECTION SOME ALONG THE ITCZ WITHIN THE PAST FEW HOURS. $$ AGUIRRE