000 AXPZ20 KNHC 110939 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC SUN JAN 11 2015 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0830 UTC. ...SPECIAL FEATURES... GULF OF TEHUANTEPEC GALE WARNING...THE PRESSURE GRADIENT REMAINS STRONG BETWEEN RIDGING EXTENDING FROM NE MEXICO TOWARD THE ISTHMUS OF TEHUANTEPEC AND TROUGHING TO THE S ALONG THE ITCZ. THIS RIDGE IS FORECAST TO PERSIST ALONG THE MEXICAN COASTAL PLAIN WHILE SLIGHTLY WEAKENING ON SUN. BY LATE MON...THE RIDGE WILL BEGIN TO BE REINFORCED BY STRONGER HIGH PRES EXTENDING SOUTH ACROSS THE CENTRAL PLAINS OF THE UNITED STATES. MINIMAL GALE CONDITIONS ARE EXPECTED ACROSS THE GULF OF TEHUANTEPEC DURING THE NEXT TWO DAYS BETWEEN 00Z-12Z. MAXIMUM SEAS AROUND 12 FT ARE EXPECTED PRIMARILY IN THE MORNING HOURS TODAY THROUGH TUE. NE SWELL FROM BOTH THE GULFS OF PAPAGAYO AND TEHUANTEPEC CONTINUES TO PRODUCE A VERY LARGE AREA OF SEAS 8 FT OR GREATER DOWNSTREAM OF THE GULFS INTO CENTRAL WATERS. THIS AREA OF SEAS PRIMARILY ATTRIBUTED TO NE TO E SWELL IS MERGING WITH LONG PERIOD NW SWELL CURRENTLY AFFECTING MOST OF THE WATERS W OF 110W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH WAS ANALYZED FROM 07N77W TO 06N97W. THE ITCZ AXIS WAS ANALYZED FROM 06N97W TO 04N95W TO 08N132W TO 07N140W. A TROUGH LIES FROM 13N133W TO 07N134W. SCATTERED MODERATE CONVECTION WAS WITHIN 90 NM EITHER SIDE OF THE AXIS BETWEEN 112N AND 118W AS WELL AS WITHIN 240 NM N AND 120 NM S OF THE AXIS BETWEEN 118W AND 126W. SCATTERED MODERATE WITHIN 180 NM W AND 240 NM E OF TROUGH. ...DISCUSSION... A COLD FRONT STRETCHES FROM 30N117W TO 23N120W WHERE IT BECOMES DISSIPATING STATIONARY TO 22N128W. A SECONDARY COLD FRONT LIES 30N121W TO 28N122W TO 26N129W. BOTH FRONTS ARE EXPECTED TO DISSIPATE LATER TODAY AS THE ASSOCIATED UPPER LEVEL TROUGH MOVES INTO NE MEXICO AND PHASES WITH BROADER TROUGHING OVER NORTH AMERICA. THE MAIN IMPACT OF THESE FRONTS IS NW SWELL. NW SWELL CURRENTLY LIES IN WATERS W OF 110W AND IS EXPECTED TO DOMINATE THE ENTIRE AREA BY TUE MORNING. ENERGY WITHIN A BROAD UPPER TROUGH CENTERED JUST W OF THE AREA IS REFLECTING A SURFACE TROUGH FROM 12N133W TO 07N134W. CONVECTION NEAR THE TROUGH IS DESCRIBED IN THE SECTION ABOVE. PRECIPITABLE WATER IMAGERY SHOWS MOISTURE IS POOLED NEAR THIS TROUGH AND UNDER AN AREA OF UPPER LEVEL SPEED DIVERGENCE. CONVECTION IS EXPECTED TO ACCOMPANY THE TROUGH THROUGH THE END OF THE FORECAST PERIOD ON TUE MORNING. THE UPPER TROUGH SUPPORTING THIS SYSTEM IS EXPECTED TO TURN NEGATIVE TILT AS IT SLOWLY MOVES EASTWARD. AT THE SURFACE...SHIP PHSG REPORTED WINDS MEETING THE ADVISORY CRITERIA JUST E OF THE TROUGH OVER THE PAST FEW HOURS. THE PRESSURE GRADIENT IN THE AREA IS EXPECTED TO INTENSIFY AS THE SUBTROPICAL RIDGE BUILDS OVER NE WATERS ONCE THE COLD FRONT DISSIPATES AND AS THE TROUGHING INCREASES. WINDS IN THE 20-25 KT RANGE ARE EXPECTED TO CONTINUE NEAR THE TROUGH OVER WATERS BETWEEN 121W AND 134W FOR THE NEXT DAY OR SO. GAP WINDS... GULF OF PANAMA...FRESH TO LOCALLY STRONG N WINDS ARE FUNNELING INTO THE GULF OF PANAMA FROM THE SW CARIBBEAN. THESE WINDS ARE EXPECTED TO DIMINISH AFTER SUNRISE TODAY AS THE PRESSURE GRADIENT OVER THE AREA WEAKENS. GULF OF PAPAGAYO...TRADE WINDS IN THE SW CARIBBEAN WILL CONTINUE TO FUNNEL INTO THE GULF OF PAPAGAYO THROUGH AT LEAST TUE MORNING. THESE WINDS ARE EXPECTED TO PULSE TO NEAR GALE FORCE DURING THE OVERNIGHT AND EARLY MORNING HOURS WITH THE AID OF THE DRAINAGE FLOW THROUGH MON MORNING. RIDGING N OF THE AREA WILL WEAKEN SLIGHTLY ON MON...KEEPING THE GAP WINDS HERE TO A FRESH TO STRONG BREEZE TUE MORNING. $$ SCHAUER