000 AXPZ20 KNHC 130907 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC TUE JAN 13 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 0700 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. WINDS TO MINIMAL GALE FORCE ARE EXPECTED THROUGH THE END OF THE FORECAST PERIOD ON THU MORNING...WITH THE AREA OF GALE FORCE WINDS EXCEPTED TO BE A BIT LARGER DURING THE PERIOD OF MAXIMUM DRAINAGE FLOW OFF THE MOUNTAINS IN THE EARLY MORNINGS AND A BIT SMALLER DURING THE DIURNAL MINIMUM OF DRAINAGE FLOW IN THE LATE AFTERNOON. SEAS IN THE 8-12 FT RANGE ARE EXPECTED IN THE GULF OF TEHUANTEPEC THROUGH THU MORNING. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH AXIS WAS ANALYZED FROM 07N78W TO 09N85W TO 06N90W. ITCZ AXIS WAS ANALYZED FROM 06N90W TO 11N124W TO 08N140W. SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION WAS WITHIN 150 NM N OF THE AXIS BETWEEN 105W AND 110W. A TROUGH EXTENDS N OF THE ITCZ FROM 17N125W TO 11N125W. SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION WAS FROM 06N TO 17N BETWEEN 115W AND 124W. ISOLATED MODERATE CONVECTION WAS FROM 10N TO 17N BETWEEN 124W AND 134W. ...DISCUSSION... ENERGY WITHIN THE BROAD UPPER TROUGH CENTERED ALONG 130W IS REFLECTING TWO TROUGHS AT THE SURFACE. THESE TROUGHS EXTEND WITHIN 390 NM N OF THE ITCZ ALONG 125W AND 138W...RESPECTIVELY. RECENT LIGHTNING DATA SHOWS THE TROUGH ALONG 125W IS MORE CONVECTIVELY ACTIVE. THIS CONVECTION IS DESCRIBED IN THE SECTION ABOVE. PRECIPITABLE WATER IMAGERY SHOWS THE MOISTURE POOLED ALONG THE ITCZ IS SPREAD OUT ACROSS THE AREA JUST AHEAD OF THESE SURFACE TROUGHS. MOISTURE SHOULD CONTINUE TO BE PLENTIFUL ACROSS THIS AREA FOR THE NEXT FEW DAYS. THE LEAD TROUGH SHOULD REMAIN MORE CONVECTIVELY ACTIVE THROUGH THE FORECAST PERIOD AS IT WILL TRACK EASTWARD IN TANDEM WITH THE AREA OF VERTICAL LIFT ASSOCIATED WITH THE REAR RIGHT QUADRANT OF THE SOUTHERLY JET ON THE E SIDE OF THE UPPER TROUGH. THE SUBTROPICAL RIDGE EXTENDS FROM 1028 MB HIGH PRESSURE NEAR 38N128W THROUGH 32N128W TO 12N106W. THE PRESSURE GRADIENT REMAINS STRONG BETWEEN THE SUBTROPICAL RIDGE AND THE AFOREMENTIONED SURFACE TROUGHS OVER W CENTRAL WATERS. THE ASCAT- A PASS FROM 0540 UTC SHOWS STRONG TO NEAR GALE FORCE WINDS WITHIN 450 NM W OF THE TROUGH ALONG 125W AND FRESH TO STRONG WINDS WITHIN 450 NM E OF THE TROUGH. THE RIDGE IS EXPECTED TO WEAKEN OVER THE NEXT TWO DAYS...DIMINISHING THE PRESSURE GRADIENT. TRADE WINDS ARE EXPECTED TO DIMINISH BELOW A FRESH TO STRONG BREEZE BY LATE WED MORNING AS A RESULT. THE ACCOMPANYING AREA OF SEAS 8 FT OR GREATER WILL SHRINK SIGNIFICANTLY AS THE WINDS DROP OFF. A WEAK COLD FRONT IS EXPECTED TO INCH INTO NW WATERS LATER TODAY AND DISSIPATE FROM 30N136W TO 26N139W WED MORNING. WINDS ARE EXPECTED TO BE A FRESH S BREEZE JUST AHEAD OF THE FRONT TODAY...WITH SEAS BUILDING TO 12 FT IN NW SWELL IN THE FAR NW WATERS BY THIS EVENING. THE NW SWELL WILL CONTINUE TO SEND SEAS OF 8 FT OR GREATER SOUTHEASTWARD INTO THE FORECAST AREA...SPANNING THE AREA W OF 126W N OF A LINE FROM 15N126W TO 10N140W BY THE END OF THE FORECAST PERIOD EARLY THU MORNING. GAP WINDS... GULF OF PAPAGAYO...TRADE WINDS IN THE SW CARIBBEAN CONTINUE TO FUNNEL THROUGH NORTHERN COSTA RICA INTO THE GULF OF PAPAGAYO. FRESH TO STRONG E-NE WINDS IN PLACE THIS MORNING ARE ALSO EXPECTED WED MORNING AND THU MORNING DURING THE MAXIMUM NOCTURNAL DRAINAGE FLOW. WINDS AND SEAS WILL BRIEFLY DIMINISH DURING THE AFTERNOON AND EVENING HOURS. GULF OF CALIFORNIA...AN UPPER LOW OVER THE U.S. GREAT BASIN WILL MAKE ITS WAY S TO THE ARIZONA/MEXICO BORDER WED BEFORE SHEARING EASTWARD THU. 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 WED AND THU. A FRESH N BREEZE IS EXPECTED OVER THE NORTHERN GULF OF CALIFORNIA WED...WITH AN OCCASIONAL STRONG BREEZE BY THU MORNING. $$ SCHAUER