000 AXPZ20 KNHC 142203 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC SUN APR 14 2013 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2145 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH AXIS WAS ANALYZED FROM 07N78W TO 06N86W TO 06N96W. ITCZ AXIS EXETNDS FROM 06N96W TO 06N110W. IT RESUMES AT 07N114W TO 07N126W TO 04N140W. NUMEROUS STRONG CONVECTION EXISTS FROM 05N TO 09N BETWEEN 82W AND 86W. SCATTERED MODERATE TO STRONG CONVECTION IS WITHIN 180 NM S OF AXIS BETWEEN 108W AND 111W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 60 NM N OF AXIS BETWEEN 136W AND 138W. SCATTERED MODERATE CONVECTION IS WITHIN 120 NM S OF AXIS BETWEEN 127W AND 131W. ...DISCUSSION... A MID/UPPER TROUGH EXTENDS FROM NEAR 03N92W NWWD TO 14N106W. ZONAL WESTERLY FLOW DOMINATES THE AREA W OF THE TROUGH. THIS FLOW BEGINS TO DIVERGE AROUND THE TROUGH E OF 115W WHICH CONTINUES TO ENHANCE THE VERTICAL MOTION FROM THE ITCZ TO 10N AND BETWEEN 106W AND 110W WHERE DEEP ATMOSPHERIC MOISTURE AND INSTABILITY IS EVIDENT. AS A RESULT ...DEEP CONVECTION AS DESCRIBED ABOVE UNDER ITCZ/MONSOON TROUGH IS CONCENTRATED ALONG AND NEAR THE ITCZ BETWEEN 108W AND 111W AS NOTED ON THE LATEST SATELLITE IMAGERY AS WELL AS THAT FROM THROUGHOUT THE DAY. UPPER LEVEL DIFFLUENCE ASSOCIATED WITH A HIGHLY AMPLIFIED RIDGE THAT STRETCHES FROM NW COLOMBIA NWWD ACROSS CENTRAL AMERICA AND TO NEAR 13N96W IS CONTRIBUTING TO LIFT NEAR AN AREA OF POOLED LOW TO MID-LEVEL MOISTURE S OF THE MONSOON TROUGH OVER THE ERN PORTION FROM 05N TO 09N BETWEEN 82W AND 86W WHERE NUMEROUS STRONG CONNECTION IS BEING OBSERVED AS DESCRIBED ABOVE UNDER ITCZ/MONSOON TROUGH. DEBRIS BLOWOFF MOISTURE...IN THE FORM OF SCATTERED TO BROKEN CIRRUS CLOUDS RELATED TO THIS CONVECTION... IS BEING CHANNELED NWD AROUND THE WRN PERIPHERY OF THE RIDGE TO ACROSS SE MEXICO...AND FROM HONDURAS SWD TO PANAMA. TO THE NE OF THE DISCUSSION AREA OVER THE WRN CONUS REGION...A MEAN UPPER TROUGH STRETCHES SWWD OVER FAR NRN BAJA CALIFORNIA SW TO NEAR 28N121W. THIS TROUGH IS BEING ENERGIZED WITH NRN STREAM ENERGY...WITH A STRONGER SHORTWAVE SYSTEM EXPECTED TO AMPLIFY THE TROUGH SIGNIFICANTLY BEGINNING ON MON THIS WILL HELP AMPLIFY THE UPPER RIDGE OVER THE FAR WRN PART OF THE AREA AS IT SHIFTS EWD. AN UPPER LOW NOTED ON SATELLITE WATER VAPOR TO BE JUST W OF THE AREA AT 27N142W WILL SLOWLY MOVE NE INTO THE FAR NW CORNER OF THE AREA THROUGH TUE. HOWEVER...A RATHER DRY AND STABLE SURROUNDING ENVIRONMENT WILL INHIBIT THE DEVELOPMENT OF ANY CONVECTION WITH THIS LOW. A DEEP LAYER TROUGH OVER THE CENTRAL PACIFIC IS ATTENDANT BY A JET STREAM BRANCH THAT ENTERS THE DISCUSSION AREA THROUGH 17N140W...AND REACHES TO NEAR 17N132W BEFORE IT BECOMES ILL-DEFINED. SCATTERED TO BROKEN CIRRUS CLOUDS ALONG AND S OF THIS JET STREAM BRANCH ARE STREAMING EWD INTO THE FAR WRN PART OF THE AREA FROM 12N TO 17N AND W OF 133W. AT THE SURFACE...A 1030 MB HIGH CENTER IS WELL N OF THE AREA AT 37N139W WITH A RIDGE EXTENDING SEWD TO 32N133W TO NEAR 21N118W. HIGH PRES COVERS THE AREA N OF 16N AND W OF 118W. THE ASCAT PASS FROM 1830 UTC THIS AFTERNOON ALONG WITH A FEW RECENT SHIP OBSERVATIONS SHOWED MAINLY LIGHT TO MODERATE NE TRADE WINDS TO THE W OF THE RIDGE AXIS. TO THE NE OF THE RIDGE AXIS THE PRES GRADEINT REMAINS TIGHT BETWEEN THE RIDGE AND BROAD LOW PRES OVER WRN INTER-MOUNTAIN U.S. THIS TIGHT GRADIENT IS PRODUCING NW TO N WINDS OF GALE FORCE OFF THE COAST OF SOUTHERN CALIFORNIA N OF THE FORECAST AREA. N SWELLS IS PROPAGATING SW FROM THIS REGION INTO NE FORECAST WATERS...WITH SEAS TO 8 FT OVER THE AREA BOUNDED FROM N OF 27N BETWEEN 120W AND 130W. A WEAK SURFACE TROUGH MOVING W ABOUT 15 KT EXTENDS FROM 10N110W TO 04N112W. TOTAL PRECIPITABLE WATER (TPW) MOISTURE COMPOSITE ANIMATION INDICATES THAT THE TROUGH IS WITHIN AN AREA OF CONCENTRATED DEEP ATMOSPHERIC MOISTURE. LATEST IR SATELLITE IMAGERY SHOWS SCATTERED MODERATE CONVECTION WITHIN 30 NM OF 11N112W. THE 1030 MB HIGH IS FORECAST TO DISSIPATE MON AFTERNOON...BUT BEFORE THEN IT WILL BE IMPINGED UPON BY A COLD FRONT TO ITS N TONIGHT...WITH HIGH PRES REORGANIZING N OF THE FRONT. TRADES WILL REMAIN WEAK WITH THE HIGH WELL N OF THE AREA...BUT THE TIGHT PRES GRADIENT BETWEEN THE HIGH AND LOWER PRES OVER THE INTER-MOUNTAIN U.S. WILL KEEP GALE FORCE WINDS ALONG THE CALIFORNIA COAST THROUGH TUE. THE ASSOCIATED NORTHERLY SWELLS WILL CONTINUE TO PROPAGATE INTO NE FORECAST WATERS...WITH SEAS EXPECTED TO BUILD AS HIGH AS 11 FT OR 12 FT N OF ABOUT 28N MON AND TUE. MARINE...CROSS-EQUATORIAL SWELLS WITH PERIODS IN EXCESS OF 20 SECONDS ON ITS LEADING EDGE HAS MADE ITS WAY TO THE ENTIRE CENTRAL AMERICAN AND MAINLAND MEXICAN COAST AS WELL AS THE BAJA CALIFORNIA PENINSULA S OF 26N. THESE SWELLS WILL CONTINUE TO STRETCH N ALONG THE BAJA CALIFORNIA PENINSULA OVERNIGHT TONIGHT WHILE DAMPENING ALONG THE REMINDER OF THE COASTLINE. SEAS OF 8 FT ARE CONFINED TO W OF THE GALAPAGOS ISLANDS S OF 09N BETWEEN 92W AND 107W AS DETECTED BY A JASON ALTIMETER PASS FROM EARLIER TODAY. THESE SEAS ARE FORECAST BY WAVEWATCH MODEL GUIDANCE TO GRADUALLY SUBSIDE TO LESS THAN 8 FT THROUGH MON MORNING. $$ AGUIRRE