000 AXPZ20 KNHC 210340 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC MON JAN 21 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0330 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... MONSOON TROUGH EXTENDS FROM 08N75W TO 02N81W TO 08N87W TO 07N91W WHERE LOW LEVEL WINDS SUGGEST THAT IT TRANSITIONS TO THE ITCZ TO 07N104W TO 07N115W TO 10N131W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 90 NM N OF THE ITCZ BETWEEN 99W-102W. ...DISCUSSION... A SMALL AND WEAK MID TO UPPER LEVEL CYCLONE HAS MOVED EWD OVER NRN BAJA CALIFORNIA WITH A TROUGH SSE TO 25N111W TO 16N110W TO 07N108W. A LARGE UPPER RIDGE IS TO THE E OF THE TROUGH COVERING THE ERN PORTION OF THE AREA N OF 05N. DIFFLUENT FLOW PATTERN BETWEEN THE SRN SEGMENT OF THE TROUGH AND RIDGE IS HELPING TO ENHANCE CONVECTION N OF ITCZ BETWEEN 99W-102W. A MID/UPPER RIDGE IS TO THE W OF THE TROUGH ALONG 124N AND N OF ABOUT 14N. A NEGATIVE-TILED LONGWAVE DEEP LAYERED TROUGH EXTENDS FROM THE NE PACIFIC SSE TO A VIGOROUS VORTEX NEAR 26N139W...WITH A TROUGH EXTENDING SW TO A BROAD BASE NEAR 11N145W. SATELLITE DERIVED WINDS DEPICTS A 75-100 KT UPPER JET STREAM BRANCH ACROSS THE SE SEMICIRCLE OF THE VORTEX. AT THE SURFACE...AN OLD COLD FRONTAL BOUNDARY LINGERS AHEAD OF THIS EWD DRIFTING LONGWAVE TROUGH ...AND STRETCHES FROM 32N138W TO 25N132W TO 16N135W TO SW OF THE AREA OF 10N140W. A BROAD ZONE OF UPPER LEVEL DIVERGENCE E OF THE TROUGH WITH UPPER LEVEL DIFFLUENCE IN PLACE CONTINUES TO ENHANCE MOSTLY SCATTERED CONVECTION ALONG AND TO WITHIN 360 NM E OF THE COLD FRONT N OF 18N. IT IS LIKELY INDUCING ISOLATED AREAS OF GALE FORCE WINDS NEAR AND WITHIN THE DEEPER CONVECTION AS WAS SUGGEST BY AN ASCAT PASS FROM JUST PAST 19 UTC THIS AFTERNOON. SE TO S WINDS 20-30 KT PREVAIL E OF THE FRONT TO 130W...WITH HIGHEST OF THESE WINDS N OF 26N. A SURFACE LOW ASSOCIATED WITH THE UPPER VORTEX IS ANALYZED AT 25N140W WITH A PRES OF 1002 MB MOVING RAPIDLY SE. THE LONG WAVE TROUGH AND ATTENDANT SURFACE LOW WILL SHIFT GRADUALLY E OVER THE NEXT 48 HOURS AND REMAIN NEGATIVELY TILTED FOR ACTIVE CONVECTION SE SEMICIRCLE...WITH COMPLEX SURFACE LOW SHIFTING SLOWLY E TO SE IN UNISON. A GALE WARNING IN THE HIGH SEAS FORECAST HAS BEEN ISSUED FOR THE NW QUADRANT OF THE LOW BEGINNING TUE EVENING DUE TO THE FORECAST TIGHT PRES GRADIENT TO ITS NW AS HIGH PRES TO ITS N BUILDS EASTWARD. HIGH SEAS IN THE RANGE OF 11-17 FT WILL PERSIST ACROSS THE NW PORTION OF THE AREA THROUGH TUE AS LARGE NW SWELL PROPAGATING THROUGH THE REGION PASSES THROUGH THIS AREA OF MIXED SWELL CREATED BY SURFACE LOW. VERY LONG PERIOD NW SWELL IS CURRENTLY MOVING THROUGH W HALF OF DISCUSSION AREA...AND HAS BEGUN TO PEAK ACROSS BAJA CALIFORNIA NORTE. BUOY DATA NETWORK N OF THE AREA ARE REPORTING LARGE NW SWELLS OF 10 FT WITH PERIODS IN EXCESS OF 18 SECONDS. THE LEADING EDGE OF THIS SWELL TRAIN IS REACHING MOST OF BAJA CALIFORNIA. LONGER PERIOD FORERUNNERS ARE MOVING OFFSHORE OF MEXICO AND W PORTIONS OF CENTRAL AMERICA ATTM...AND WILL ALSO PEAK IN THE NEXT 48 HOURS. EXPOSED REEFS AND COASTS WITH NW EXPOSURE WILL SEE VERY SIGNIFICANT WAVE ENERGY...AND PRODUCE VERY STRONG AND POWERFUL SURF...WIDESPREAD RIP CURRENTS...AND COASTAL EROSION DURING HIGH TIDES. GAP WINDS... CONTINUED NORTHEASTERLY WINDS IN SW GULF OF MEXICO ARE MOVING ACROSS CHIVELA PASS AND BRINGING GALE FORCE N-NE WINDS INTO GULF OF TEHUANTEPEC. WINDS ARE EXPECTED TO DIMINISH TO LESS AROUND MID MORNING ON MON. MODEL GUIDANCE SUGGESTS THAT WINDS WILL PICK UP AGAIN TO MINIMAL GALE FORCE MON NIGHT AND PULSATE BACK DOWN TO BELOW GALE FORCE DURING TUE MORNING BEFORE AGAIN INCREASING TO MINIMAL GALE FORCE ONCE AGAIN TUE NIGHT. WILL LEAVE GALE WARNING POSTED AS IS IN THE NEXT ISSUANCE OF THE HIGH SEAS FORECAST. CURRENT NE WINDS TO GALE FORCE ACROSS THE SW CARIBBEAN REINFORCE FRESH TO STRONG NE WINDS THROUGH GULF OF PAPAGAYO THROUGH NEXT 48 HRS WITH STRONGEST WINDS NOTED IN EARLY MORNINGS AS DOWNSLOPE DRAINAGE WINDS ADDS STRENGTH TO WIND FIELD. STRONG NE WINDS ACROSS SW CARIBBEAN ALSO CONTRIBUTES TO FRESH N BREEZE OVER GULF OF PANAMA THROUGH LATE MON. EXPECT N TO NE WINDS OF 20 TO 25 KT TO CONTINUE THROUGH GULF OF PANAMA THROUGH TUE EVENING WITH ADDED MOMENTUM FROM THE THE NE GALE FORCE WINDS IN THE SW CARIBBEAN SEA. $$ AGUIRRE