000 AXPZ20 KNHC 210329 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Thu Nov 21 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 0000 UTC surface analysis and satellite imagery through 0200 UTC. ...TROPICAL WAVES... A tropical wave is along 94W south of 12N, moving west at 10 kt. A few clusters of scattered moderate to strong thunderstorms are from 07.5N to 13.5N between 93W and 99W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 09N74W TO 06.5N80W TO low pres 1010 MB near 06.5N87.5W TO low pres 1010 MB near 10N112.5W TO 08N119W TO 11N130W. The ITCZ then continues from 11N130W TO beyond 10.5N140W. Scattered moderate convection is noted from 05.5N TO 10N between 83W and 89W. Scattered moderate isolated strong convection is noted from 08N to 13.5N between 94W and 103W, from 08N to 16.5N between 103W and 115W, and from 08.5N to 13.5N W of 135W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A cold front is moving southeastward across northern portions of Baja California Norte this evening, and has reached the Bahia Sebastian Vizcaino. Strong to near gale force SW winds are ongoing over the northern Gulf of California ahead of the front. An altimeter pass from around 2000 UTC showed seas as high as 11 ft in the far northern Gulf of California, just offshore of Puerto Penasco. The front will move across much of the region before stalling and weakening over the southern Gulf of California and Baja California Sur near Cabo San Lazaro on Fri. Expect the strong W to SW winds to persist over the northern Gulf of California tonight through Thu morning. Off the Pacific coast of Baja California, mostly moderate to fresh NW winds will follow the front, then diminish through Thu as high pressure builds into the region in the wake of the front. Longer period NW swell is following the front as well. NW swell producing seas of 10 to 11 ft currently reach as far south as Guadalupe Island. The swell will propagate SE and encompass the entire offshore waters of Baja California, with heights of 8 to 10 ft reaching as far south as 20N through late Thu, before starting to subside below 8 ft into Sat. Farther south, clusters of showers and thunderstorms have diminished this evening across the waters beyond 120 nm off Cabo Corrientes. This is in an area of unstable deep layer tropical moisture, with lift provided on the eastern side of an mid/upper trough well west of the area. Some of this cloud cover and convection aloft will move northeastward across Las Tres Marias area and the entrance to Gulf of California through Thu as the trough drifts eastward. The showers and thunderstorms will diminish through late Thu as the main moisture is shunted west of the area. Seas are 4 to 6 ft in a mix of NW and SW swell over offshore Mexican waters south of Cabo Corrientes. Winds may briefly increase fresh to strong off Cabo Corrientes late Fri as high pressure builds in the wake of the cold front. Winds are diminishing through the Gulf of Tehuantepec. Looking ahead, another round of strong gap winds can be expected across the Gulf of Tehuantepec by late Sat into early Mon. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh to strong NE-E winds are expected across the Gulf of Papagayo through Thu with seas building to around 7 ft each night. Elsewhere, gentle to moderate southwest 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. REMAINDER OF THE AREA... The remnant low of Tropical Depression Twenty-One-E has moved WNW and merged with a broader area of weak low pressure, now centered near 10N112.5W, to the northwest of Clipperton Island. The low pressure is drifting westward and is interacting with a mid/upper trough west of the area. This interaction is supporting a large area of showers and thunderstorms from near the low pressure northward to just east of the Revillagigedo Islands. This merged area of low pressure is forecast to gradually shift west across the tropics for the next few days. Easterly winds to around 20 kt could persist across the N semicircle of this low during this time. A cold front reaches from northern Baja California Norte to 25N120W to 24N126W to 28N140W. The front will move as far south as 18N to 20N through Fri before stalling and dissipating. The front has temporarily disrupted the subtropical ridge, producing only moderate trade winds farther south into the deep tropics north of the ITCZ. Fresh NE winds are possible west of 130W by late week as high pressure builds behind the front farther east. This will coincide with a push of long period NW swell forecast to reach the forecast waters north of 20N west of 130W by Thu night, with seas peaking near 12 or 13 ft by Fri. Looking ahead, global models are indicating another vigorous deep layer trough digging into the waters north of 20N Sat into Sun. A broad surface trough may form between 120W and 125W north of 18N related to the upper feature. Fresh to strong winds and building seas are to be expected between the trough and high pressure north of the area. $$ Stripling