000 AXPZ20 KNHC 240316 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC TUE APR 24 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0045 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE ITCZ AXIS EXTENDS FROM 09N85W TO 05N95W TO 07N109W TO 04N120W TO 04N127W. SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION LIES WITHIN 90 NM N AND 120 NM S OF THE AXIS BETWEEN 106W AND 114W. SCATTERED MODERATE CONVECTION CAN BE FOUND WITHIN 150 NM S OF THE AXIS BETWEEN 116W AND 119W. ...DISCUSSION... A STRONG CUT OFF LOW ALOFT IS CENTERED NORTH OF THE FORECAST AREA NEAR 34N134W AND EXTENDS A TROUGH SOUTHWARD ALONG 134W TO 25N THEN SOUTHWESTWARD TO 19N140W. BROAD RIDGING CENTERED JUST OFFSHORE OF BAJA CALIFORNIA DOMINATES THE REMAINDER OF THE FORECAST AREA ALOFT N OF 15N. BROADLY DIFFLUENT UPPER LEVEL FLOW IS FOUND IN MUCH OF THE REGION N OF 10N AND E OF THE TROUGH AXIS...WITH THE FLOW SPLIT BETWEEN SOUTHERN STREAM WESTERLIES CENTERED ALONG 15N AND SOUTH-SOUTHWESTERLY FLOW ON THE LEADING EDGE OF THE CUT OFF LOW. THE LEFT FRONT QUADRANT OF THE 80-100 KT SOUTHERN STREAM JET LIES NEAR A MAXIMA OF PRECIPITABLE WATER THAT COINCIDES WITH A SURFACE TROUGH FROM 07N128W TO 01N130W. SCATTERED MODERATE CONVECTION FOUND FROM 05N TO 09N BETWEEN 125W AND 130W IS BEING ENHANCED BY THE LIFT OF THIS MOIST AIR MASS BY THE DIFFLUENCE ALOFT. A LARGER REGION OF MULTI-LAYERED CLOUDINESS AND SCATTERED SHOWERS PRIMARILY FROM 10N TO 22N BETWEEN 113W AND 132W IS ALSO BENEFITING FROM THESE CONDITIONS. FARTHER SOUTH...AN UPPER LEVEL TROUGH AXIS LIES FROM 10N120W TO 00N108W AND A RIDGE AXIS LIES TO ITS EAST ALONG 08N EAST OF 112W. DIFFLUENT FLOW ABOUT THIS RIDGE AXIS IS ACTING TO ENHANCE THE SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION ALONG THE ITCZ DESCRIBED IN THE SECTION ABOVE. A 1019 MB HIGH PRES SYSTEM IS CENTERED NEAR 25N119W. THE HIGH HAS BEEN WEAKENED BY THE TROUGHING ALOFT. THIS HAS RESULTED IN TRADE WINDS LESS THAN 20 KT OVER THE FORECAST AREA DUE TO THE AND THE WEAKENED PRES GRADIENT BETWEEN IT AND THE ITCZ. A COLD FRONT ASSOCIATED WITH THE CUT OFF LOW ALOFT EXTENDS FROM 30N128W TO 22N136W. NORTH TO NORTHWEST WINDS TO 25 KT LIE OVER FAR NORTHWEST WATERS BEHIND THE FRONT ACCORDING TO SHIP WFLG WHO REPORTED 24 KT NEAR 27N139W AT 0000 UTC. THE DEEP LAYER LOW IS FORECAST TO GRADUALLY WEAKEN AS IT SLOWLY MOVES SOUTHEASTWARD THROUGH WED...CARRYING THE FRONT EASTWARD WITH IT. THE STRONGEST WINDS SHOULD REMAIN OVER NORTH WATERS TO THE WEST OF THE SURFACE LOW...WITH STRONG WINDS EXPECTED THROUGH TUE DIMINISHING TO FRESH ON WEDNESDAY. NORTHWEST SWELL WILL ALLOW SEAS TO BUILD TO THE 13-15 FT RANGE BEHIND THE FRONT TOMORROW BEFORE GRADUALLY SUBSIDING. GAP WINDS... GULF OF TEHUANTEPEC...HIGH PRES OVER THE WESTERN GULF OF MEXICO BEHIND A STRONG LATE SEASON COLD FRONT HAS TIGHTENED THE PRES GRADIENT ACROSS SOUTHERN MEXICO RESULTING IN WINDS TO GALE FORCE THROUGH THE GULF OF TEHUANTEPEC. THE 1858 UTC LOW RESOLUTION OSCAT PASS CAPTURED WINDS TO GALE FORCE WITH STRENGTHENING OF THE PRES GRADIENT EXPECTED THIS EVENING AS HIGH PRES IN THE GULF OF MEXICO SHIFTS SOUTHWARD. 40 KT NORTH-NORTHEASTERLY WINDS THIS EVENING WILL DIMINISH BELOW GALE FORCE BY TUE AFTERNOON AS THE HIGH PRES SYSTEM SHIFTS INTO THE NORTHEASTERN GULF OF MEXICO. GULF OF PAPAGAYO...THE SOUTHERN MIGRATION OF THE HIGH PRES SYSTEM IN THE WESTERN GULF OF MEXICO HAS INCREASED THE PRES GRADIENT OVER CENTRAL AMERICA. THE 1720 UTC OSCAT PASS REPORTED WINDS TO 20 KT IN THE GULF OF PAPAGAYO. FRESH TO STRONG NORTHEAST WINDS WILL SPREAD DOWNWIND OF THE GULF OF PAPAGAYO OVERNIGHT TONIGHT. WINDS ARE EXPECTED TO REMAIN FRESH TO STRONG DOWNWIND OF PAPAGAYO THROUGH WEDNESDAY. GULF OF PANAMA...THE PRES GRADIENT OVER CENTRAL AMERICA HAS SHIFTED EASTWARD ENOUGH TO ALLOW THE NORTHERLY FLOW TO FUNNEL INTO THE GULF OF PANAMA FROM THE CARIBBEAN. SHIP DPJK REPORTED 21 KT N WINDS NEAR 07N80W AT 0000 UTC. THESE CONDITIONS WILL CONTINUE THROUGH THE END OF THE FORECAST PERIOD WED EVENING. $$ SCHAUER