000 AXPZ20 KNHC 141605 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC WED JAN 14 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1500 UTC. ...SPECIAL FEATURES... GULF OF TEHUANTEPEC GALE WARNING...NORTHERLY WIND FLOW BETWEEN A STALLED FRONTAL BOUNDARY THAT IS IN THE SOUTHWESTERN CORNER OF THE GULF OF MEXICO...AND RIDGING ALONG THE NORTHEASTERN MEXICAN COAST IS FUNNELING THROUGH THE ISTHMUS OF TEHUANTEPEC. THIS PATTERN SHOULD SEE LITTLE CHANGE DURING THE NEXT TWO DAYS. THE WIND SPEEDS ARE FORECAST TO MAINTAIN THE LEVEL OF MINIMAL GALE FORCE THROUGH FRIDAY. THE AREA OF GALE FORCE WINDS IS EXPECTED TO BE LARGER DURING THE PERIOD OF MAXIMUM DRAINAGE FLOW OFF THE MOUNTAINS IN THE EARLY MORNINGS...AND THE AREA IS EXPECTED TO BE SMALLER DURING THE DIURNAL MINIMUM OF DRAINAGE FLOW IN THE LATE AFTERNOON. SEA HEIGHTS IN THE 9-13 FOOT RANGE ARE EXPECTED IN THE GULF OF TEHUANTEPEC THROUGH FRIDAY. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH PASSES THROUGH 07N78W TO 08N83W TO 06N90W. THE ITCZ CONTINUES FROM 06N90W TO 04N96W...TO A 1010 MB LOW PRESSURE CENTER THAT IS NEAR 09N113W...TO 08N130W TO 10N135W. CONVECTIVE PRECIPITATION...SCATTERED STRONG FROM 04N TO 05N BETWEEN 85W AND 87W. A 1010 MB LOW PRESSURE CENTER IS NEAR 09N113W. CONVECTIVE PRECIPITATION...NUMEROUS STRONG FROM 07N TO 12N BETWEEN 110W AND 114W. ...DISCUSSION... A BROAD UPPER TROUGH PASSES THROUGH 32N132W TO 24N128W TO 15N128W TO 07N125W. A 1010 MB LOW PRESSURE CENTER IS NEAR 09N113W. NUMEROUS STRONG CONVECTIVE PRECIPITATION COVERS THE AREA FROM 07N TO 12N BETWEEN 110W AND 114W. PRECIPITABLE WATER IMAGERY SHOWS LOW-TO MID-LEVEL MOISTURE POOLED ALONG THE ITCZ IN THIS AREA. THIS SHORTWAVE TROUGH WILL MOVE RAPIDLY NORTHEASTWARD AWAY FROM THE AREA OF POOLED MOISTURE AS A NEW BATCH OF SHORTWAVE ENERGY MOVES INTO THE BACKSIDE OF THE BROAD TROUGH. THIS NEW ENERGY WILL BECOME THE FOCUS FOR PRECIPITATION BY THURSDAY AS IT MOVES INTO THE LEADING EDGE OF THE BROAD UPPER TROUGH. THE SUBTROPICAL RIDGE EXTENDS FROM 1020 MB HIGH PRESSURE NEAR 34N124W THROUGH 27N120W TO 17N117W. THE PRESSURE GRADIENT HAS WEAKENED A BIT BETWEEN THE SUBTROPICAL RIDGE AND THE AFOREMENTIONED THE 1010 MB LOW PRESSURE CENTER. SCATTEROMETER DATA SHOW FRESH TO STRONG TRADE WINDS FROM 09N TO 11N BETWEEN 111W AND 114W. THE RIDGE WILL CONTINUE TO WEAKEN DURING THE NEXT TWO DAYS...RELAXING THE PRESSURE GRADIENT. TRADE WINDS ARE EXPECTED TO DIMINISH BELOW THE LEVEL OF A FRESH TO STRONG BREEZE ON THURSDAY AS A RESULT. THE ACCOMPANYING AREA OF SEAS 8 FEET OR GREATER WILL SHRINK SIGNIFICANTLY AS THE WINDS DROP OFF. A WEAKENING COLD FRONT PASSES THROUGH 30N133W BEYOND 27N140W... IN THE NORTHWESTERN CORNER OF THE FORECAST AREA. THE LATEST SCATTEROMETER DATA SHOW A FRESH SOUTHERLY BREEZE JUST AHEAD OF THE FRONT. SEAS HIGHER THAN 8 FEET IN NW SWELL HAVE MOVED OUT AHEAD OF THE FRONT...BUT THE HIGHEST SEAS...TO 13 FT...ARE TO THE WEST OF THE FRONT. THE NW SWELL WILL CONTINUE TO SEND SEAS OF 8 FT OR GREATER SOUTHEASTWARD INTO THE FORECAST AREA. GAP WINDS... GULF OF PAPAGAYO...TRADE WINDS IN THE SOUTHWESTERN CORNER OF THE CARIBBEAN SEA CONTINUE TO FUNNEL THROUGH NORTHERN COSTA RICA INTO THE GULF OF PAPAGAYO. FRESH TO STRONG EAST-TO-NORTHEAST WINDS ARE IN PLACE THIS MORNING ARE ALSO EXPECTED THU MORNING AND FRI MORNING DURING THE PERIOD OF MAXIMUM NOCTURNAL DRAINAGE FLOW. WINDS AND SEAS WILL BRIEFLY DIMINISH DURING THE AFTERNOON AND EVENING HOURS. GULF OF CALIFORNIA...AN UPPER LOW OVER ARIZONA WILL SLOWLY MOVE SE TODAY BEFORE SHEARING EASTWARD INTO TEXAS THURSDAY. AT THE SURFACE...THE PRESSURE GRADIENT WILL BUILD BETWEEN LEE SIDE TROUGHING ALONG THE W SLOPES OF THE SIERRA MADRE OCCIDENTAL AND INCREASED RIDGING OVER THE GREAT BASIN IN THE WAKE OF THE SYSTEM TODAY AND THU. THE NORTHERN GULF OF CALIFORNIA HAS A FRESH N-NW BREEZE IN PLACE THIS MORNING AND MAY SEE AN OCCASIONAL STRONG BREEZE N OF 28N DURING THE NEXT DAY OR SO. $$ MT