000 AXPZ20 KNHC 121617 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC MON MAR 12 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1500 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH IS NOT PRESENT ACROSS E PACIFIC. ITCZ AXIS EXTENDS FROM 03.5N92W TO S OF THE EQUATOR AT 113W. SCATTERED MODERATE TO STRONG CONVECTION IS NOTED WITHIN 150 NM N OF AXIS BETWEEN 93W AND 103W. ...DISCUSSION... A GENERAL ZONAL FLOW PATTERN ALOFT DOMINATES MOST OF THE LOCAL AREA THIS MORNING N OF 23N...WITH A MODEST PERTURBATION ALONG 121W FROM 10N TO 15N...WHILE A TUTT AXIS EXTENDS FROM THE W CARIBBEAN W-SW INTO THE EPAC ALONG 90W WHERE A WEAK MID LEVEL CYCLONE HAS CARVED A TROUGH SWD ALONG 89W/90W BEYOND THE EQUATOR. THIS TROUGHING ALONG 90W IS CONTRIBUTING TO UNSTABLE ATMOSPHERIC CONDITIONS AND ACTIVE WEATHER ALONG THE ITCZ E OF 100W. N OF 23N...A BROAD TROUGH CONTINUES TO DOMINATE THE NE PACIFIC WITH ITS SRN PERIPHERY EXTENDING S INTO N PORTIONS OF THE DISCUSSION AREA. SHORTWAVES CONTINUE TO MOVE THROUGH THE BASE OF THE TROUGH...WITH ONE CURRENTLY ALONG 120W AND APPROACHING SRN CALIFORNIA AND THE BAJA PENINSULA...WITH A MORE SIGNIFICANT SHORTWAVE AND ASSOCIATED WEAKENING CYCLONE EXTENDING FROM 34N136W TO 24N143W. A JET CORE WITH WINDS 75-90 KT IS S OF THIS FEATURE...JUST S OF 20N...BETWEEN 130W AND 150W. ACTIVE CONVECTION CONTINUES ALONG THE ITCZ IN THE E CENTRAL PACIFIC... WHICH REMAINS S OF THE EQUATOR S OF 113W. EQUATORIAL UPPER RIDGING PERSISTS OVER THIS CONVECTION AND IS CENTERED S OF THE EQUATOR...AIDING IN PRODUCING THIS ZONAL FLOW ALOFT SWD TO ALONG THE EQUATOR. A WEAKENING FRONTAL TROUGH OVER THE FAR NW WATERS HAS RECENTLY DISSIPATED. HOWEVER A MORE SIGNIFICANT FRONT SUPPORTING BY THE SECOND AND MORE SIGNIFICANT SHORTWAVE IS FORECAST TO MOVE INTO THE NW PORTION OF THE AREA LATE TONIGHT INTO TUE WITH SW WINDS POSSIBLY INCREASING TO 20 KT N OF 29N WITHIN 300 NM AHEAD OF IT. THE FRONT IS FORECAST TO WEAKEN FROM NEAR 30N133W TO 26N140W BY LATE TUE NIGHT AS THE BROAD UPPER TROUGH TRANSLATED EASTWARD. THE MAIN IMPACT OF THESE FRONTS MOVING INTO THE NORTHERN WATERS THROUGH THE NEXT 48 HRS WILL BE THE ASSOCIATED PULSES OF LONG PERIOD NW SWELLS SWEEPING SE ACROSS THE AREA WATERS. NWLY SWELL CURRENTLY ACROSS NW PORTIONS OF THE AREA WILL DECAY SOME THIS MORNING ALLOWING FOR SEAS TO SUBSIDE SLIGHTLY INTO THE 9-10 FT RANGE. ANOTHER PULSE OF NW SWELL WILL ARRIVE WITH THE STRONGER COLD FRONT TUE MORNING AND YIELD SEAS OF 9-12 FT N OF 24N AND W OF 127W BY TUE EVENING. ELSEWHERE AT THE SURFACE...THE EPAC HIGH PRES RIDGE WAS CENTERED ON A 1033 MB HIGH OVER THE NORTH-CENTRAL PACIFIC WELL NW OF THE HAWAIIAN ISLANDS. THE RIDGE BRIDGED ACROSS THE RECENTLY DISSIPATED FRONTAL TROUGH AND EXTENDS TO THE SRN BAJA PENINSULA ALONG 112W. THE PRES GRADIENT TO THE S OF THE RIDGE WAS INDUCING NE TRADES OF 20 KT GENERALLY FROM 05N TO 13N W OF 133W...WITH SEAS IN THE 9-11 FT RANGE ...HIGHEST LOCATED W OF 130W. THIS AREA OF TRADES IS FORECAST TO DIMINISH IN AREAL COVERAGE TO A NARROW ZONE OF NEAR 20 KT TRADES FROM 07-10N W OF 132W DURING THE NEXT 24-48 HOURS AS THE CENTRAL PACIFIC HIGH WEAKENS AND SHIFTS W. E OF 110W...WINDS ARE DOMINATED BY GAP WIND FLOW SPILLING FROM THE CARIBBEAN ACROSS CENTRAL AMERICA AND THEN DOWNSTREAM ACROSS THE EPAC...WITH WEAK WINDS S OF 05N. GAP WINDS... THE GULF OF TEHUANTEPEC...THERE IS LITTLE TO NO FORCING MECHANISM ACROSS THE GULF OF MEXICO CURRENTLY TO DRIVE WINDS THROUGH THE GULF OF TEHUANTEPEC...AND ONLY A NARROW NOCTURNAL DRAINAGE FLOW OF 20-25 KT WAS FOUND THIS MORNING. HOWEVER...HIGH WILL BEGIN TO BUILD ACROSS THE GULF OF MEXICO AND THE W CARIBBEAN DURING THE NEXT FEW DAYS TO INCREASE WINDS AND THE LENGTH OF THIS PLUME DOWNWIND OF TEHUANTEPEC. WINDS MAY BRIEFLY APPROACH 30 KT WITHIN THE NEXT 36-48 HRS...AND MAY PULSE LATE AT NIGHT TO NEAR GALE FORCE WED AND THU NIGHT. THE GULF OF PAPAGAYO...FRESH TRADES ACROSS THE CARIBBEAN CONTINUE TO FUEL GAP WIND FLOW ACROSS CENTRAL AMERICA THEN THROUGH THE GULF OF PAPAGAYO AND JUST DOWNWIND OF THE GULF FONSECA...EXTENDING WELL SW TO NEAR 93W THIS MORNING...WITH DOWNWIND SEAS PRESENTLY AT 6 TO 9 FT. AS STATED ABOVE...HIGH PRES IS EXPECTED TO BUILD S AND SW ACROSS THE GULF OF MEXICO AND WRN CARIBBEAN IN THE NEXT 24-48 HOURS AND WILL REINFORCE THIS FLOW THROUGH THROUGH THE GULF. THE WINDS ARE EXPECTED TO SPREAD DOWNSTREAM FROM THE GULF TO 94W OR 95W DURING THE NEXT 24-48 HRS WITH NE TO E WINDS NEAR 20 KT REACHING AS FAR W AS 115W. THE GULF OF PANAMA...TRADES IN THE SOUTHWESTERN CARIBBEAN SEA WILL CONTINUE TO SUPPORT PULSES OF FRESH NORTHERLY FLOW ACROSS THE ISTHMUS OF PANAMA AND ACROSS THE GULF OF PANAMA. SEAS ARE LESS THAN 8 FT THERE...BUT ARE EXPECTED TO BUILD TO 8 FT WED NIGHT. $$ STRIPLING