000 AXPZ20 KNHC 221525 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1525 UTC Fri Nov 22 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 1200 UTC surface analysis and satellite imagery through 1500 UTC. ...TROPICAL WAVES... A tropical wave axis is along 100W, south of 14N, moving west at around 15 kt. Scattered moderate to strong convection is noted from 07N to 10N between 100W and 105W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 07N78W to to 1009 mb low pressure near 10N118W. The ITCZ continues from 10N120W to to 09N118W to beyond 09N140W. Scattered moderate isolated strong convection is noted from 10N to 15N between 105W and 120W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A stalling cold front analyzed earlier across the southern Gulf of California and Baja California Sur has dissipated. Gentle to moderate NW winds persist along the length of the Gulf, with 2 to 4 ft seas. Moderate northerly winds are noted off the Pacific coast of Baja California, although some ship observations indicate strong winds near gap areas. Seas over the offshore waters are still 8 to 10 ft due to lingering long period NW swell. A weak pressure ridge is building in the wake of the front off the Baja California coast. This will allow winds to diminish slightly off the coast, but increase slightly over the Gulf of California into Sun. Offshore wave heights will diminish to 5 to 7 ft as the NW swell decays. Looking ahead, a cold core upper low near 30N130W is currently pivoting to the southeast, and will be over the waters just west of Guadalupe Island by late Sat and off Punta Eugenia by Tue. This will draw deep layer tropical moisture into Baja California Sur and the southern and central Gulf of California by early next week. Global models are indicating associated surface low pressure will develop over the Revillagigedo Islands early in the week. The low pressure will track across Los Cabos into Sinaloa, bringing unsettled weather across the region from Cabo Corrientes through Baja California Sur early to mid week including strong winds, locally high seas, and scattered to numerous thunderstorms. A cold front will follow, moving into the waters off Baja California Norte and the northern Gulf of California by mid week, accompanied by another round of large, long period NW swell in open waters. Farther south, a few thunderstorms are ongoing along the Mexican coast near Acapulco. This is probably related to the late season tropical wave moving across the region near 100W. This will diminish through today, although isolated thunderstorms may persist off the Guerrero coast through tonight. Expect fresh to strong gap winds into the Gulf of Tehuantepec late Sat through Sun night as high pressure builds north of the region behind a weak cold front. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh NE-E winds are expected to pulse across the Gulf of Papagayo today with seas to around 5-6 ft. Offshore winds will then diminish to less than 15 kt through the weekend. Gentle to moderate SW monsoonal flow will continue across the offshore waters of Costa Rica, Panama, Colombia, and Ecuador for the next several days, along with light to moderate long period SW swell. Convergent westerly flow will support occasional scattered showers and thunderstorms off the Colombian coast through early next week. REMAINDER OF THE AREA... A broad area of low pressure along the convergence zone centered near 10N118W is drifting westward and interacting with an upper level trough. This interaction is supporting showers and a few thunderstorms just north of the low, as well as north of the monsoon trough between 105W and 120W. The low will shift westward the next few days. Easterly winds to 20 kt are expected in the northern semicircle of the low as the pressure gradient increases. The subtropical ridge remains weakened due to an earlier front moving over the waters north of 20N, and a dissipating front moving south of 30N west of 135W. Recent altimeter passes indicated seas of 8 to 12 ft north of 25N, in an area of long period NW to N swell. NW swell in excess of 8 ft will encompass the region west of 120W through Sat. Meanwhile high pressure building northwest of the area will support fresh trade winds west of 130W. Looking ahead, global models are indicating another vigorous deep layer trough digging into the waters N of 20N Sat and Sun, with a broad surface trough forming between 120W and 125W north of 18N related to this feature. A broad area of fresh to strong winds and building seas is expected between the trough and the high pressure northwest of the area Sun into early next week due to this developing pattern. $$ Christensen