000 AXPZ20 KNHC 250905 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0900 UTC Wed Dec 25 2019 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 0900 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 09N84W to 07N90W to 06N103W. The ITCZ continues from 06N103W to 09N111W to beyond 08N140W. Scattered moderate convection was noted from 05N to 07N between 102W and 106W, and from 08N to 10N between 112W and 119W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Gulf of Tehuantepec...High pressure continues to weaken over the Gulf of Mexico, with the pressure gradient loosening over the Gulf of Tehuantepec region. Winds are still reaching near gale force with the added component of nocturnal drainage flow over the area. Winds will pulse to fresh to strong the next few nights before diminishing. The next strong gap wind event is possible late Sunday into early Monday. Farther north, NW swell propagating across the waters off Baja California continues to subside, with seas in the 6-8 ft range. Seas over this area will subside below 8 ft today. A cold front will shift into the waters off Baja California Norte Thu, with strengthening winds both ahead and behind the front Thu and Fri off the coast of Baja California Norte. The front will usher in a large set of NW swell, with seas reaching near 20 ft Thu. The swell will spread southward, bringing seas 8 ft or greater to the waters off all of the Baja California peninsula, reaching as far south as the Revillagigedo Islands by early Sat. Seas will slowly subside through the weekend. The cold front will shift across Baja California Norte and the northern Gulf of California by early Fri, strengthening winds to the far northern Gulf of California Fri. Looking ahead, winds may increase slightly by Sat across the Gulf of California and off Cabo Corrientes as high pressure builds in the wake of the front. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh to strong winds are expected across the Gulf of Papagayo and downwind to near 90W through the next several days. Elsewhere, gentle to moderate south to southwest monsoon flow will persist across the offshore waters of Costa Rica, Panama, Colombia, and Ecuador, while light to gentle flow will dominate across the Gulf of Panama. REMAINDER OF THE AREA... A ridge extends from 1026 mb high pressure centered near 33N147W toward the Revillagigedo Islands. Overnight scatterometer pass indicated fresh to strong winds over the waters N of the ITCZ to near 20N and west of 120W due to the pressure gradient between the ridge and lower pressure in the vicinity of the ITCZ. Overnight altimeter data showed a large area of seas greater than 8 ft covering the waters west of a line from Baja California Sur to near 00N138W, primarily in NW swell. Seas are reaching near 12 ft over the far western waters in the area of strong trades where the NW swell is mixing with shorter period NE wind waves. The ridge will start to weaken today, loosening the pressure gradient and diminishing tradewind flow to 20 kt or less by Thu. The weakened ridge will enable a cold front to move into the northern waters Thu. The front will spread across the waters north of 20N and east of 125W through late Thu, bringing strong winds to the waters N of 25N and E of 125W. The front will also usher in a set of large NW swell into the area, with seas peaking near 20 ft on Thu. Areal coverage of 8 ft seas across the forecast waters will decrease over the next 24 hours before the next set of NW swell moves into the area. This new set of NW swell will propagate SE across the forecast waters, bringing 8 ft or greater seas to the waters N of 10N and W of 110W by early Sat. Looking ahead, another cold front over the north central Pacific will move toward the waters north of 25N and west of 130W late Sat into Sun. High pressure building behind this front will help to bring an increase to the tradewinds from 15N to 25N west of 125W by Sun. $$ AL