000 AXPZ20 KNHC 260240 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Tue Nov 26 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 0130 UTC. ...SPECIAL FEATURE... A large area of unsettled weather is presently occurring well offshore and SW of Baja California Sur, supported by a broad and energetic upper level low centered near 25N123W. A complex 1007 mb surface low pressure center has developed today near 20N119W, where scattered to locally numerous moderate to strong thunderstorms are occurring within 300 nm E through SE of the low. The upper trough is forecast to shift southward through Tue and then NE towards Baja California Wed and Thu. This will continue to spread multilayered clouds and increasing showers and thunderstorms from the offshore waters of Baja California Sur into the coast Tue through Wed. The low pressure system is expected to also shift E-NE towards the Baja coast late Tue through Wed and promote gale force southerly winds across the waters of Cabo San Lucas Wed morning through the afternoon, and then shift E-NE into the southern Gulf of California Wed evening and night. Seas during this time will build to 10-12 ft and possibly higher, both across the offshore waters and inside the southern Gulf of California. ...TROPICAL WAVES... The axis of a tropical wave is near 119W-120W and has become absorbed within the area of unsettled weather described above. Associated tropical moisture will contribute to heavy rainfall potential across Baja California Sur during the next 2 days. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 10N75W TO 06N91W. The ITCZ continues from 07N91W TO 05.5N101W TO 12N113W, then resumes from 14N122W TO 09N132W TO beyond 09N140W. Scattered moderate to strong convection is noted from 08N to 14.5N between 117W and 126W and from 08N to 11N between 126W and 140W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A broad and deep layered upper level low centered roughly near 25N123W will gradually shift S through Tue, and has already induced a 1007 mb surface low near 20N119W today. This system will draw deep layer tropical moisture from the tropics over Baja California Sur and the southern Gulf of California through mid week, supporting widespread showers and thunderstorms spreading NE across the region. Scattered showers and isolated thunderstorms aloft are already streaming northeastward across south and central portions of Baja California and across the Gulf of California south of the Tiburon Basin. The surface low is expected to pass N of the Revillagigedo Islands and move across Baja California Sur and into Sinaloa Wed through Wed night, bringing gale force winds to the waters off Baja California Sur, and the southern Gulf of California. Accompanying heavy rainfall may also produce flash flooding and landslides. See special features section above. Elsewhere, large NW swell will move across the northern waters Tue and Tue night. A cold front will cross the Baja California waters Thu into Fri, accompanied by another round of large, long period NW swell. Over the Gulf of Tehuantepec, strong northerly gap winds from Sun night diminished to around 15 kt this afternoon as the local pressure gradient has weakened, and will remain variable at 15 kt or less through Thu. Strong northerly gap winds will return to Tehuantepec Thu evening and night. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh to occasionally strong NE to E winds will pulse across the Gulf of Papagayo region through the week, with seas generally remaining less than 8 ft. Gentle to moderate SW monsoonal flow will persist across the offshore waters of Costa Rica, Panama, Colombia, and Ecuador for the next several days, along with moderate long period SW swell supporting 4-7 ft seas. REMAINDER OF THE AREA... A broad surface trough extends across the waters along about 20N between 120W and 128W, supported by an upper level low sinking slowly south over the region. Scattered moderate to strong convection is noted from 17N to 22N between 113W and 119W. Elsewhere, a large area of fresh to strong NE trades prevails west of 125W between the ITCZ and high pressure centered north of the region. Morning altimeter data sampled near the strongest winds revealed 9-14 ft seas across these waters. The broad upper level low will help to deepen the surface low near 20N119W over the next 2 days, while low level troughing persists to the SW of this low and into the tropics. Expect strong to near gale force winds and building seas as this low shifts NE into the offshore waters of Baja California Sur tonight through early Wed. Meanwhile the strong pressure gradient currently west of the low will maintain strong trades through Wed morning, while seas of 9-14 ft currently west of 125W will subside slightly to 9-12 ft by Wed. Looking ahead, a cold front will drop southward into the northern waters Wed night and Thu, followed by another round of large, long period NW swell. Combined seas may build to 16 ft by Thu west of Guadalupe Island. Seas greater than 8 ft will cover most of the region north of 20N by late Thu and persist through Fri. $$ Stripling