000 AXPZ20 KNHC 030301 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC FRI AUG 03 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0045 UTC. ...TROPICAL WAVES... THE SOUTHERN END OF A TROPICAL WAVE OVER CENTRAL AMERICA CURRENTLY LIES ALONG 86W N OF 10N AND IS MOVING W AROUND 15 KT. SCATTERED MODERATE CONVECTION WAS FROM 04N TO 08 BETWEEN 81W AND 90W AND FROM 08N TO 10N E OF 86W...INCLUDING OVER INLAND PORTION OF PANAMA AND COSTA RICA. SHOWERS AND THUNDERSTORMS WILL CONTINUE WITH THIS WAVE AS IT MOVES W INTO THE PACIFIC. WINDS ARE CURRENTLY A MODERATE BREEZE OR LESS NEAR THE WAVE. THOSE WIND CONDITIONS ARE EXPECTED TO CONTINUE THROUGH SAT. A TROPICAL WAVE LIES ALONG 101W FROM 10N TO 16N. THE WAVE IS MOVING W AROUND 5-10 KT. SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION WAS FROM 07N TO 11N BETWEEN 94W AND 101W...IN THE REGION SW OF THE WAVE AND CLOSEST TO THE MONSOON TROUGH. THE WAVE CONTINUES TO BE IN AN AREA OF SUBSIDENCE ON THE EAST SIDE OF AN UPPER ANTICYCLONE CENTERED NEAR 15N110W AND LOWER PRECIPITABLE WATER VALUES THAN THE OTHER TROPICAL WAVES IN THE PACIFIC. WINDS ARE ONLY AS STRONG AS A MODERATE BREEZE WITH THIS WAVE. A TROPICAL WAVE STRETCHES FROM 17N117W TO 11N119W AND IS MOVING W AROUND 10-15 KT. SCATTERED MODERATE CONVECTION WAS WITHIN 180 NM EITHER SIDE OF WAVE FROM 12N TO 17N. THE CONVECTION WITH THE WAVE HAS FLARED OVER THE LAST 12 HOURS IN THE REGION WHERE THE WAVE CROSSES THE RIDGE AXIS ALOFT AND UPPER DIFFLUENCE IS PRESENT. PRECIPITABLE WATER IMAGERY STILL SHOWS PLENTIFUL LOW LEVEL MOSITURE NEAR THE WAVE. THE 1808 UTC ASCAT PASS SHOWS WINDS ARE GENERALLY A MODERATE BREEZE NEAR THE WAVE...WITH A FRESH BREEZE FOUND NEAR THE CONVECTION. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH AXIS WAS ANALYZED FROM 08N78W TO 11N95W TO 09N106W. ITCZ AXIS WAS ANALYZED FROM 09N106W TO 11N115W THEN CONTINUES FROM 11N121W TO 09N130W TO 10N140W. SCATTERED MODERATE CONVECTION WAS WITHIN 120 NM S OF THE AXIS E OF 80W...WITHIN 150 NM N OF THE AXIS BETWEEN 94W AND 97W...AND WITHIN 90 NM EITHER SIDE OF THE AXIS BETWEEN 121W AND 123W. SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION WAS WITHIN 240 NM EITHER SIDE OF AXIS W OF 125W. ...DISCUSSION... THE 1031 MB SUBTROPICAL HIGH NEAR 40N140W IS FORECAST TO CONTINUE MOVING NW OVER THE NEXT TWO DAYS...WEAKENING THE RIDGING OVER THE FORECAST AREA. THE BELT OF FRESH TO STRONG TRADE WINDS CURRENTLY FOUND N OF THE ITCZ AND W OF 130W WILL SHRINK WESTWARD AS THE SUBTROPICAL HIGH MIGRATES AND DIMINISH OVER THE FORECAST AREA BY SAT EVENING. A STRONG SOUTH PACIFIC SUBTROPICAL RIDGE IS CURRENTLY IN PLACE AND IS FORCING A MODERATE TO FRESH SE BREEZE PRIMARILY S OF 06N BETWEEN 120W AND 130W. CROSS-EQUATORIAL SOUTHERLY SWELL CONTINUES TO MOVE AS FAR N AS 04N BETWEEN 95W AND 128W. THE LEADING EDGE OF THIS SWELL HAS PERIODS IN EXCESS OF 20 SECONDS. IT WILL PASS THE GALAPAGOS TONIGHT AND REACH THE COASTLINE FROM PANAMA THROUGH SOUTHERN MEXICO ON FRI BEFORE MOVING NORTHWARD INTO THE SOUTHERN GULF OF CALIFORNIA AND THE PACIFIC COAST OF BAJA CALIFORNIA ON SAT. INTERESTS ALONG THE COAST SHOULD BE AWARE OF THE POTENTIAL FOR HIGH SURF AND POSSIBLY SOME COMPLICATIONS ENTERING HARBORS AND INLETS. SWELL HEIGHTS TO 10 FT CAN BE EXPECTED AS FAR N AS 06N THROUGH SAT EVENING. AN UPPER TROUGH LIES OVER N WATERS FROM 32N130W TO 27N122W TO 20N128W TO 19N140W. THE SOUTHERN END OF THE TROUGH HAS BECOME ZONAL AS THE UPPER ENERGY IN THE NORTHERN PORTION OF THE TROUGH LIFTS OUT TO THE NE. DIFFLUENT SW FLOW ALOFT BETWEEN THE TROUGH AND AN UPPER RIDGE THAT EXTENDS FROM THE AN ANTICYCLONE NEAR 15N110W TO 14N140W IS VENTING LARGE AREAS OF CONVECTION ALONG THE ITCZ. THIS CONVECTION COINCIDES WITH SOME OF THE HIGHEST PRECIPITABLE WATER VALUES IN THE FORECAST AREA AS WELL AS AN AREA OF MODERATE UPPER DIFFLUENCE. THESE CONDITIONS ARE EXPECTED TO CONTINUE THROUGH SAT. THIS CONVECTION IS DESCRIBED IN THE SECTION ABOVE. THE SURFACE PRESSURE GRADIENT WILL INCREASE IN THE EVENING HOURS ALONG THE CENTRAL COAST OF BAJA CALIFORNIA OVER THE NEXT FEW DAYS AS DIURNALLY LOWER PRESSURE OVER MAINLAND MEXICO BUTTS UP AGAINST THE SUBTROPICAL RIDGE. THIS WILL BRIEFLY INCREASE THE WINDS TO A FRESH BREEZE IN THE REGION EACH EVENING. $$ SCHAUER