000 AXPZ20 KNHC 201512 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC MON JAN 20 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 1330 UTC. ...SPECIAL FEATURE... GULF OF TEHUANTEPEC GALE WARNING...THE 0545 UTC OSCAT PASS CONFIRMED GALE CONDITIONS WERE IN PLACE IN THE GULF OF TEHUANTEPEC. THE GALE WARNING REMAINS UP UNTIL AFTER THE PERIOD OF PEAK DIURNAL DRAINAGE OFF THE MOUNTAINS LATER THIS MORNING. WINDS IN THE GULF OF MEXICO ARE ALREADY BEGINNING TO SHIFT MORE EASTERLY...CUTTING OFF THE FLOW THROUGH CHIVELA PASS. WINDS ARE EXPECTED TO REMAIN BELOW GALE FORCE UNTIL TUE EVENING WHEN A COLD FRONT MAKES ITS WAY THROUGH THE PASS...WITH A BRIEF PERIOD OF STORM-FORCE WINDS POSSIBLE AROUND 22/06Z. A PLUME OF LARGE NE SWELL CONTINUES TO PROPAGATE AWAY FROM THE GULF OF TEHUANTEPEC. SEAS WITHIN THIS PLUME ARE EXPECTED TO GRADUALLY SUBSIDE OVER THE NEXT DAY OR SO...WITH AN AREA OF SEAS 8 FT IN NW SWELL OVERTAKING THE PLUME BY WED. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH AXIS WAS ANALYZED FROM 06N77W TO 06N80W TO 08N85W TO 04N91W. THE ITCZ AXIS WAS ANALYZED FROM 04N91W TO 06N103W TO 04N115W TO 06N120W THEN CONTINUES FROM 06N125W TO 05N130W TO 06N140W. SCATTERED MODERATE CONVECTION WAS WITHIN 120 NM S OF THE AXIS BETWEEN 87W AND 90W. NUMEROUS MODERATE TO STRONG CONVECTION WAS WITHIN 270 NM N OF THE AXIS BETWEEN 100W AND 106W. A TROUGH LIES NEAR THE ITCZ FROM 16N118W TO 06N121W. SCATTERED MODERATE TO STRONG CONVECTION WAS BETWEEN 180 NM AND 360 NM E OF THE TROUGH FROM 06N TO 10N AS WELL AS FROM 13N TO 20N BETWEEN 113W AND 118W. ...DISCUSSION... THE LEADING EDGE OF A NW SWELL TRAIN...WITH WAVE PERIODS IN THE 19-21 SECOND RANGE...STRETCHES FROM N OF ACAPULCO MEXICO TO NEAR 00N110W. THE LEADING EDGE OF THIS SWELL TRAIN WILL STRETCH FROM COSTA RICA TO THE GALAPAGOS ISLANDS TUE AND MOVE TO THE COAST OF COLOMBIA AND ECUADOR BY WED. A SECOND BATCH OF NW SWELL HAS ENTERED FAR NW WATERS...WITH SEAS TO 17 FT AND WAVE PERIODS IN THE 18-20 SECOND RANGE. THE LEADING EDGE OF THIS SWELL WILL REACH FROM THE NORTHERN BAJA CALIFORNIA PENINSULA TO 00N130W TUE MORNING AND FROM CABO SAN LUCAS MEXICO TO 00N125W WED MORNING. A NEGATIVELY TILTED UPPER TROUGH EXTENDS FROM WELL N-NW OF THE AREA THROUGH 30N140W TO 07N117W. THIS TROUGHING HAS DISRUPTED THE DEEP-LAYER RIDGING OFTEN IN PLACE IN THE REGION. THIS HAS WEAKENED THE TRADE WINDS TO A MODERATE BREEZE OR LESS. A SURFACE TROUGH ASSOCIATED WITH THE TROUGHING ALOFT IS FOUND FROM 16N118W TO 06N121W. DEEP CONVECTION BOTH N AS WELL AS E OF THE TROUGH IS NOTED IN THE SECTION ABOVE. THE SURFACE TROUGH IS EXPECTED TO REMAIN A FOCUS FOR CONVECTION AS IT SHIFTS N-NE OVER THE NEXT 24 HOURS. AN AREA OF MODERATE TO FRESH EASTERLY WINDS HAS BECOME ESTABLISHED ON THE N EDGE OF THE SURFACE TROUGH...WITH SEAS BUILDING TO 8-10 FT IN THIS AREA TODAY AND QUICKLY MERGING WITH SEAS 8 FT OR GREATER IN NW SWELL SWEEPING SE THROUGH THE FORECAST AREA. THE SURFACE TROUGH WILL WEAKEN AND CONVECTION WILL WANE AS THE SUPPORTING SPOKE IN THE LONG-WAVE UPPER TROUGH WEAKENS TUE. GAP WINDS... GULF OF PAPAGAYO...THE GRADIENT BETWEEN THE SURFACE RIDGE EXTENDING FROM 1022 MB HIGH PRESSURE IN THE SW GULF OF MEXICO TO NORTHEASTERN COSTA RICA AND LOWER PRESSURE ASSOCIATED WITH THE MONSOON TROUGH TO THE S IS CONTINUING TO DRIVE STRONG TO NEAR GALE FORCE WINDS IN THE GULF OF PAPAGAYO THIS MORNING. SEAS HAVE PEAKED AROUND 10 FT. THE HIGH PRESSURE TO THE N WILL WEAKEN LATER TODAY...ALLOWING WINDS IN THE GULF OF PAPAGAYO TO DROP DOWN TO A FRESH TO STRONG BREEZE BY TUE MORNING AND DIMINISH FURTHER BY TUE AFTERNOON. $$ SCHAUER