000 AXPZ20 KNHC 241003 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 927 UTC Sun Dec 24 2017 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 FEATURE... ...Gulf of Tehuantepec Gale-Force Winds... A strong cold front bisects the Gulf of Mexico from the Florida Panhandle to the Isthmus of Tehuantepec has induced a gap wind event over the Gulf of Tehuantepec. Gale force winds are presently occurring over the Gulf of Tehuantepec as nocturnal drainage flow augments the winds. The gale-force winds over the Gulf of Tehuantepec will subside to just below gale force today, then increase once again to gale force tonight. Gale-force winds will then persist until Tue morning as a reinforcing shot of cold air enters the Gulf of Mexico. Seas in the Gulf of Tehuantepec should peak around 12 ft on Monday morning, then remain 8 ft or greater through at least Wednesday night. Please refer to the latest high seas forecast issued under AWIPS/WMO headers HSFEP2/FZPN03 for more details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 07N77W to 06N93W to 07N102W. The ITCZ continues from 07N102W to 07N130W to beyond 10N140W. Numerous moderate and scattered strong convection is observed from 08N to 12N between 110W and 116W. Scattered moderate and isolated strong convection is found elsewhere from 07N to 14N between 109W and 117W. Scattered moderate and isolated strong convection is also located from 05.5N to 08N between 94W and 98W and within 90 nm either side of a line from 07N128W to 08N132W to 16N138W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please refer to the special features section above for details on the Gulf of Tehuantepec Gale event. Gulf of California: The fresh to strong winds that have prevailed over the Gulf during the past couple of days have subsided to moderate to fresh speeds. The flow will continue to diminish tonight as high pressure over the SW United States weakens. Benign marine conditions are then expected over the Gulf through the middle of next week. Gentle to moderate winds and seas of 4 to 6 ft will prevail elsewhere into mid week next week. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Strong gap winds over the Gulf of Papagayo will continue pulsing through Wednesday night. Seas will peak around 8 ft. NE swell to 9 ft will clip the western offshore waters of Guatemala Monday and Tuesday as swell disperse from the Gulf of Tehuantepec gap wind event. Otherwise, gentle to moderate winds and seas of 5 to 7 ft can be expected during the next several days. REMAINDER OF THE AREA... A 1010 mb extratropical low centered near 31.5N138W is moving NE away from the NW corner of the discussion area this morning. Gale force winds in the SE quadrant of the low have subsided as the low begins to weaken. The low will continue weakening today as it continues lifting slowly NE, which will allow strong SE to S winds over the forecast waters to subside. Residual seas of 8 to 12 ft in mixed SE and NW swell W of a line from 30N131W to 22N140W this evening will disperse to the SE and subside to between 8 and 9 ft by Tue morning as NW swell disperse and mix with E swell. Scattered moderate convection is currently occurring N of 23N and W of 135W over the discussion waters associated with this system. Please refer to the latest high seas forecast issued under AWIPS/WMO headers HSFEP2/FZPN03 for more details. Elsewhere, moderate to fresh winds will prevail with seas between 6 and 8 ft. $$ CAM