000 AXPZ20 KNHC 201822 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC SUN MAR 20 2011 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1545 UTC. ...ITCZ... THE INTERTROPICAL CONVERGENCE ZONE IS CENTERED ALONG 6N86W 3N99W 2N108W 5N121W 3N131W 7N140W. SCATTERED MODERATE CONVECTION IS WITHIN 120 NM N OF THE ITCZ AXIS BETWEEN 90W AND 94W. ...DISCUSSION... A VIGOROUS DEEP LAYER TROUGH OFF THE WEST COAST OF THE U.S EXTENDS SSE INTO THE DISCUSSION AREA THROUGH 32N125W...AND S TO 23N125W THEN SW TO 18N130W TO W OF THE AREA 19N140W. A JET STREAM BRANCH DIVES SOUTHEASTWARD INTO THE BACKSIDE OF THE TROUGH ENTERING THE AREA THROUGH 32N139W THEN ROUNDS THE BASE OF THE TROUGH REACHING NE TO 24N122W...AND TO ACROSS CENTRAL BAJA CALIFORNIA TO NW MEXICO. UPPER AIR DATA SHOWS MAXIMUM JET CORE WINDS OF 60-90 KT ON THE EASTERN SIDE OF THE TROUGH N OF 20N. THIS WINDS ASSOCIATED WITH THE JET CONTINUE TO ADVECT UPPER LEVEL MOISTURE IN THE FORM OF BROKEN TO SCATTERED MID AND HIGH LEVEL CLOUDS NORTHEASTWARD TO OVER MUCH OF CALIFORNIA AND NORTHERN BAJA CALIFORNIA TO WELL INLAND THE WESTERN U.S. THE SURFACE COLD FRONT ASSOCIATED WITH THE DEEP LAYER TROUGH HAS PUSHED INTO THE FAR NORTHERN WATERS ALONG A PSN FROM 32N123W TO 28N133W TO NW OF THE AREA AT 29N140W. A VERY IMPRESSIVE COLD AIR MASS BEHIND THE FRONT IS SEEN IS DENOTED BY THE STRATOCUMULUS CLOUD FIELD SPREADING SSE INTO THE FAR NORTHERN BOUNDARY OF THE AREA BEHIND THE FRONT IN NW FLOW OF 20-25 KT. AHEAD OF THE FRONT...THE PRES GRADIENT IS TIGHT ENOUGH TO ALLOW FOR SW GALE WINDS OF 25-35 KT N OF 28N WITHIN 120 NM E OF FRONT. THESE WINDS WILL DIMINISH TO LESS THAN GALE FORCE BY LATE THIS AFTERNOON...AND INTO EARLY THIS EVENING AS THE FRONT BEGINS TO WEAKEN. BY EARLY TUE...THE FRONT WILL BE DISSIPATING INLAND THE WESTERN U.S. A NEW COLD FRONT WILL THEN BEGIN TO MOVE INTO THE FAR NW PORTION PRECEDED BY INCREASING SW WINDS...AND YET ANOTHER NW SWELL TRAIN WILL BE MOVING INTO THE NORTHERN WATERS. SEAS WILL REMAIN HIGH DUE TO LARGE LONG PERIOD NW SWELLS WITH MAXIMUM HEIGHTS OF 14 FT WITHIN ABOUT 120-180 NM E OF THE FRONT AND UP TO 16 FT N OF THE FRONT E OF 134W AND 12 FT ELSEWHERE N OF THE FRONT. A WEAK 1015 MB HIGH CENTER IS ANALYZED TO THE SE OF THE FRONT NEAR 24N118W...BUT IS EXPECTED TO DISSIPATE IN 24 HOURS. STRONGER HIGH PRES IS OVER THE FAR WESTERN SECTION OF THE AREA TO THE SW OF THE FRONT. TO ITS S...NE TO E TRADE WINDS OF 20-25 KT ARE OCCURRING FROM 8N-16N W OF 125W WITH SEAS THERE IN THE 8-10 FT RANGE. HOWEVER AS THE RIDGE SHIFTS S AND WEAKENS WITH THE EASTWARD PROGRESSION OF THE FRONT...THE TRADES WILL RESPOND BY DIMINISHING SLIGHTLY TO AROUND 20 KT. BY TUE MORNING...THE RIDGE WILL REBUILD OVER NW WATERS IN THE WAKE OF THE DISSIPATED FRONT AND THE TRADES OVER WESTERN WATERS WILL THEN EXPAND NORTHWARD IN RESPONSE. AN UPPER RIDGE AXIS EXTENDS FROM A BROAD ANTICYCLONE LOCATED OVER CENTRAL MEXICO NEAR 19N100W TO 10N126W. WATER VAPOR IMAGERY SHOWS DRY AIR ALOFT OVER MUCH OF THE AREA S OF 20N BETWEEN 85W AND 105W IN THE VICINITY OF THE ANTICYCLONE. MOST OF THIS AREA IS VOID OF DEEP CONVECTION WITH THE EXCEPTION OF IMMEDIATELY N OF THE ITCZ FROM 90W-97W WHERE LOW TO MID LEVEL MOISTURE IS FOUND...AND IN COMBINATION WITH DIFFLUENCE ALOFT BETWEEN THE SOUTHERN EDGE OF THE ANTICYCLONIC CIRCULATION AND A 25-45 KT SOUTHWESTERLY UPPER JET THAT ROUNDS THE WESTERN PERIPHERY OF A MID/UPPER RIDGE THAT EXTENDS FROM COLOMBIA SW TO NEAR 5N93W IS ENOUGH TO PROVIDE FOR THE NECESSARY LIFT TO RESULT IN SCATTERED MODERATE CONVECTION AS DESCRIBED ABOVE UNDER ITCZ. FARTHER SE...A 1009 MB SURFACE LOW ALONG THE COAST OF COLOMBIA NEAR 04N78W IS EXPECTED TO REMAIN STATIOANRY OVER THE NEXT 48 HOURS. SCATTERED MODERATE CONVECTION IS FROM 2N-6N BETWEEN 78W-80W. THIS AREA COINCIDES WITH THE HIGHEST PRECIPITABLE WATER VALUES OVER THE FORECAST AREA AND BROAD DIFFLUENCE BETWEEN RIDGE AXES N AND S OF THE EQUATOR. GAP WINDS... GULF OF CALIFORNIA...SW WINDS IN THE NORTHERN GULF OF CALIFORNIA ARE EXPECTED TO INCREASE ABOVE ADVISORY CRITERIA THIS EVENING AHEAD OF THE PREVIOUSLY MENTIONED STRONG COLD FRONT. THE FRONT WILL MOVE INTO THE AREA LATE MON AND QUICKLY DISSIPATE. WINDS THEN DIMINISH TO LESS THAN 20 KT BY LATE MON NIGHT. GULF OF TEHUANTEPEC...FRESH TO STRONG N TO NE WINDS ARE EXPECTED TO CONTINUE OVER THE NEXT TWO DAYS WITH A DIURNAL MAXIMUM COINCIDING WITH MORNING DRAINAGE FLOW THROUGH THE PASS. THIS WILL ALLOW FOR WINDS TO PEAK UP TO 30 KT EARLY IN THE MORNINGS. GULF OF PAPAGAYO...A STRONG PRES GRADIENT BETWEEN HIGH PRES OVER CENTRAL AMERICA TO THE N AND LOW PRES ALONG THE W COAST OF COLOMBIA IS EXPECTED TO CONTINUE WITH LITTLE CHANGE OVER THE NEXT FEW DAYS. FRESH TO STRONG NE TO E WINDS WILL CONTINUE TO FUNNEL FROM THE CARIBBEAN THROUGH CENTRAL AMERICA THROUGH TUE MORNING. GULF OF PANAMA...PERSISTENT PRES GRADIENT BETWEEN THE LOW/TROUGH NEAR THE COAST OF COLOMBIA AND HIGH PRES OVER CENTRAL AMERICA WILL SUSTAIN N WINDS OF 20 KT WITH LITTLE CHANGE EXPECTED IN WINDS AND SEAS THROUGH 24 HOURS...THEN WINDS MAY INCREASE TO 25 KT BY 48 HOURS. $$ AGUIRRE