000 AXPZ20 KNHC 141555 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC FRI NOV 14 2014 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 1545 UTC. ...SPECIAL FEATURES... GULF OF TEHUANTEPEC GALE WARNING...A VERY TIGHT PRES GRADIENT INDUCED BETWEEN A 1031 MB HIGH PRES OVER NE MEXICO AND A STATIONARY FRONT DRAPED ACROSS THE SW GULF OF MEXICO HAS SET UP OVER SOUTHEASTERN MEXICO AND THE ISTHMUS OF TEHUANTEPEC. COLD DENSE AIR USHERED IN BY THE HIGH PRES HAS PUSHED SOUTHWARD TO OVER THE GULF WHILE MIXING DOWN TO THE SEA SURFACE WHERE VERY WARM TEMPERATURES ARE ANALYZED. THE RESULTANT N-NE GALE FORCE WINDS BEGAN LAST NIGHT THROUGH THE GULF WITH IN THE RANGE OF 30- 40 KT. AN 1100 UTC OBSERVATION FROM SHIP WITH CALL SIGN "VRED4" REPORTED NE 35 KT WINDS AT LOCATION OF 14N96W. A PARTIAL ASCAT-B PASS FROM NEAR 0400 UTC LAST NIGHT INDICATED 30-40 KT N WINDS ACROSS THE CENTRAL PORTION OF THE GULF OF TEHUANTEPEC. SEAS IN THE GULF HAVE BUILT UP TO THE RANGE OF 11-18 FT. THIS REMAINS IN LINE WITH THE LATEST TAFB-NWPS MODEL OUTPUT FOR THE AREA. THE GALE FORCE WINDS WILL CONTINUE THROUGH EARLY SAT BEFORE SUBSIDING TO JUST UNDER GALE FORCE BY EARLY IN THE AFTERNOON. WINDS WILL CONTINUE TO DIMINISH TO 20 KT OR LESS SAT NIGHT WHILE RESIDUAL NE SWELLS PROPAGATE SW-W WITH 8-9 FT SEAS COVERING THE WATERS FROM 06N-12N BETWEEN 100W AND 108W BY THEN. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... MONSOON TROUGH AXIS EXTENDS FROM 09N84W TO 06N89W TO 08N100W TO 09N110W T0 08N120W TO 08N124W. ITCZ EXTENDS FROM 08N124W TO LOW PRES NEAR 10N131W 1011 MB TO 06N140W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 60 NM N AND 120 NM S OF THE ITCZ BETWEEN 131W-133W. SCATTERED MODERATE CONVECTION EXISTS FROM 05N-08N BETWEEN 111W-122W. ...DISCUSSION... IN THE UPPER LEVELS...BROAD SCALE RIDING COVERS THE FAR EASTERN PORTION OF THE AREA E OF ABOUT 104W...WITH THE PARENT ANTICYCLONE CENTERED OVER THE WESTERN CARIBBEAN SEA AT 18N81W. A TROUGH EXTENDS FROM THE WESTERN U.S. SW TO 32N121W TO 24N128W TO NEAR 18N135W. ANOTHER TROUGH IS ALONG 115N FROM 07N-25N WITH A WEAK CYCLONIC CIRCULATION ALONG IT NEAR 19N117W. BROAD RIDGING COVERS THE AREA TO THE W OF THE FIRST TROUGH. WATER VAPOR IMAGERY SHOWS MAINLY DRY AND STABLE AIR THROUGHOUT WITH THE EXCEPTIONS OF THE BASE OF THE EASTERN MOST TROUGH WHERE DIFFLUENT FLOW THERE IN COMBINATION WITH S-SW SURFACE FLOW S OF THE MONSOON TROUGH IS HELPING TO CONTINUE TO PRODUCE SCATTERED MODERATE CONVECTION AS DESCRIBED ABOVE UNDER ITCZ/MONSOON TROUGH. THE OTHER AREA OF DEEP LAYER MOISTURE IS TIED TO CONVECTION ASSOCIATED WITH THE 1011 MB LOW NEAR 10N131W AS WELL AS TO THE S OF THE ITCZ BRANCH IN THAT VICINITY AS MENTIONED ABOVE. EXTENSIVE MID TO UPPER LEVEL MOISTURE...IN THE FORM OF MOSTLY BROKEN CIRRUS CLOUDS...IS STREAMING ENE OVER THE NW SECTION OF THE AREA AHEAD OF A LARGE TROUGH WELL W OF THE AREA. AT THE SURFACE...A WEAK 1020 MB HIGH CENTER IS LOCATED AT 29N126W WITH A RIDGE SE TO 22N119W...AND ANOTHER RIDGE SW TO 22N140W. THE HIGH IS FORECAST TO MOVE N TO NEAR 32N125W BY EARLY SAT. A WEAK SURFACE TROUGH IS MOVING WESTWARD ALONG THE SOUTHERN PERIPHERY OF THE HIGH AND EXTENDS FROM 21N126W SE TO NEAR 15N120W. SHORTWAVE IR SATELLITE IMAGERY CONTINUES TO SHOW A WELL DEFINED SWIRL OF LOW CLOUDS IN ASSOCIATION WITH THIS TROUGH. THE PRES GRADIENT BETWEEN THE TROUGH AND THE HIGH TO THE N WILL RESULT IN AN AREA OF MAINLY FRESH EASTERLY WINDS NEAR THE NORTHERN END OF THE TROUGH THROUGH TONIGHT. LONG PERIOD NW SWELL WITH A LEADING EDGE PERIOD OF 17-18 SEC CONTINUES TO PROPAGATE ACROSS MUCH OF THE FORECAST WATERS W OF 110W. SEAS IN THE RANGE OF 8-10 FT ARE PRESENT TO THE W OF A LINE FROM 32N115W TO 18N121W TO 05N104W PRIMARILY IN NW LONG PERIOD SWELL. THE SWELL ENERGY IS FORECAST BY WAVEWATCH GUIDANCE TO GRADUALLY DISSIPATE OVER THE NEXT 48 HOURS ALLOWING FOR THE 8-12 FT SEAS TO LOWER TO 9 FT W OF A LINE FROM 32N137W TO 28N140W BY EARLY SUN...AND TO 8 FT IN MIXED SE AND NW SWELL WITHIN AN AREA BOUNDED BY A LINE FROM 27N132W TO 19N129W TO 12N137W TO 17N136W TO 27N132W UNDER WINDS OF 20 KT OR LESS. A NEW REINFORCING SET OF NW SWELLS IS FORECAST BY THE GUIDANCE TO ARRIVE IN THE NW CORNER BY LATE TONIGHT AHEAD OF AN APPROACHING FRONTAL SYSTEM WHICH WILL STALL OUT NEAR 32N142W ON SAT. SEAS PRODUCED BY THESE SWELLS ARE EXPECTED TO REACH 8-10 FT ON SAT AND CHANGE LITTLE THROUGH SUN. SLY WIND FLOW AHEAD OF THE FRONTAL SYSTEM IS FORECAST TO INCREASE TO 20-25 KT ON SUN. GULF OF PAPAGAYO...THE PRES GRADIENT WILL STRENGTHEN ACROSS THE WESTERN CARIBBEAN DURING THE WEEKEND SUPPORTING NE WINDS OF 20- 25 KT ACROSS THE GULF OF PAPAGAYO COMMENCING EARLY SAT MORNING. THESE WINDS ARE FORECAST TO EXPAND WSW FROM THE GULF TO NEAR 90W EARLY SAT...AND TO NEAR 91W BY EARLY SAT AFTERNOON WITH SEAS UP 9 OR 10 FT. THE WINDS WILL DIMINISH TO 15-20 KT BY 36 HOURS WITH SEAS TO 8 FT IN NE SWELL...AND TO LESS THAN 8 FT BY EARLY ON SUN. LOOKING AHEAD...A STRONG LOW PRES SYSTEM ASSOCIATED WITH THE AFOREMENTIONED FRONTAL SYSTEM WILL BRING AN INCREASE IN WINDS AND SEAS ACROSS THE NW WATERS BEGINNING SUN NIGHT AND INTO MON. MODEL GUIDANCE SUGGESTS WINDS OF 20-30 KT JUST AHEAD AND BEHIND THE FRONT WITH SEAS BUILDING TO 9-14 FT BY EARLY MON. IN ADDITION...EXPECT INCREASING NW WINDS OF 20-25 KT IN THE FAR NORTHERN GULF OF CALIFORNIA LATE SUN INTO MON WITH SEAS BUILDING TO 8 FT AS A TIGHT PRES GRADIENT DEVELOPS THERE. $$ AGUIRRE