000 AXPZ20 KNHC 252219 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Mon Nov 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 1800 UTC surface analysis and satellite imagery through 2100 UTC. ...SPECIAL FEATURE... An increasing area of unsettled weather is presently occurring well offshore and SW of Baja California Sur, supported by a broad and energetic upper level low north of 18N and centered near 26N123W. A 1008 mb surface low pressure center has developed 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 NE towards the Baja coast late Tue through Wed and promote gale force southerly winds across the waters of Cabo San Lucas late 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. ...TROPICAL WAVES... The axis of a tropical wave is near 119W from 04N to 20N, moving W-NW 5 to 10 kt. This wave and associated moisture has begun to merge with a large area of unsettled weather that is being influenced by a deep layered upper low NW of this area. Scattered moderate to strong convection associated with this wave is noted from 08N to 14N between 118W and 122W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 11N73W TO 09N79W TO 08N91W. The ITCZ extends from 08N91W TO 06N97W TO 15N117.5W, then continues from 13N122W TO 08.5N130W TO beyond 09N140W. Scattered moderate to strong convection is noted from 08N to 14N between 118W and 132W and from 08.5N to 10N between 134W and 138W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A broad upper level low centered roughly near 26N123W will gradually shift S through Tue, and has already induced a 1008 mb surface low near 20N119W today. This system will draw deep layer tropical moisture over Baja California Sur and the southern Gulf of California through mid week, supporting widespread showers and thunderstorms spreading NE across the region. The resulting surface low is expected to track NE north of the Revillagigedo Islands and move across Baja California Sur into Sinaloa Wed and Wed night, bringing gale force winds to the waters off Baja California Sur, and the southern Gulf of California. 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 last night have diminished to around 15 kt this afternoon as the local pressure gradient has weakened. 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 north of 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 16N to 27.5N between 113W and 120W. 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 9-12 ft seas across these waters. The broad upper level low will help to deepen the surface low near 20N119W, 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 a strong pressure gradient west of the low and will maintain strong trades with seas building to 10-14 ft west of 125W by tonight. 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