000 AXPZ20 KNHC 130352 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Wed Nov 11 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 0215 UTC. ...SPECIAL FEATURE... Gulf of Tehuantepec Gale Warning: The strong arctic cold front that pushed well inland Mexico during the day has become stationary as of 00Z. Strong high pressure of 10350 mb in the wake of the front is analyzed over northern Mexico near Monterrey. The associated very tight pressure gradient is pressing southward along the eastern slopes of the Sierra Oriental mountains. The resultant strong winds have already begin to funnel through Chivela Pass and out into the Gulf of Tehunatepec leading to gale force north to northeast winds there. The last visible satellite images showed low-level clouds streamers spreading outward from the far southeastern and westward sections of the Gulf of Tehuantepec, which is indicative of an ongoing wind gap event. The north to northeast winds are expected to peak near 45 kt in the Gulf of Tehuantepec late tonight, with wave heights building to near 20 ft at that time. It is possible that these winds may attain occasional gusts to storm force. The very tight pressure gradient will relax on Wed as the area of high pressure shifts eastward, with winds diminishing below gale force late Wed night. Mixed northeast and southwest swell will build wave heights up to 9 ft well downstream from the Gulf of Tehuantepec to within an area from 05N to 10N between 90W and 104W by early Thu. Another gale force gap wind event is possible across the region Fri through Sat night. See the latest High Seas Forecast under AWIPS/WMO headers HSFEP2/FZPN03 KNHC or the website https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for further details. ...TROPICAL WAVES... A tropical wave with axis along 126W from 04N to 19N is moving westward at about 10-15 kt. Low pressure of 1010 mb is along the wave near 12N126W. Scattered moderate to strong convection is within 120 nm of the low in the northeast quadrant. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from along the coast of northwest Colombia to across northern Costa Rica and to 09N83W to 08N100W to low pressure of 1010 mb near 11N113W to low pressure of 1010 mb near 12N126W and to 08N135W. Scattered moderate to strong convection is seen from 05N to 08N between 78W and 82W. Scattered moderate to isolated strong convection is within 120 nm north of the trough between 93W and 97W and also within 60 nm of trough between 93W and 95W. Scattered moderate convection is within 120 nm north of the trough between 99W and 103W and within 120 nm north of the between 107W and 113W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A strong Gulf of Tehuantepec gale force gap began Tue afternoon. Please see the Special Feature section above for more details on the significant event. Elsewhere, a ridge dominates the offshore forecast waters west of Baja California, supporting gentle to moderate northerly winds, and wave heights of 4 to 6 ft. Little change is expected through Thu. Strong high pressure building across north and central Mexico is supporting fresh to locally strong northwest to north winds and wave heights of 7 to 8 ft seas near the entrance of the Gulf of California and farther south between Cabo Corrientes and Los Cabos. Winds and seas are expected to diminish by tonight as the high pressure shifts eastward. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gentle to moderate southwesterly monsoonal flow will continue across the offshore waters of Costa Rica, Panama, Colombia, and Ecuador the next several days. Wave heights will remain in the 4- 7 ft range. Large wave heights generated by a strong gale force gap wind event in the Gulf of Tehuantepec will reach the offshore waters of Guatemala and El Salvador tonight into Wed, with wave heights building to 10 to 14 ft in northerly swell. REMAINDER OF THE AREA... A dissipating cold front extends from near 32N138W to 26N140W. Wave heights of up to 8 ft in northwest are west of the front. Large-long period northwest well associated with an intense low pressure system in central northern Pacific will reach the northwest waters on Thu. Wave heights associated with this next event will peak near 13 or 14 ft over the far NW waters by Thu night. Low pressure of 1010 mb is observed near 12N126W moving westward about 10 kt. Satellite imagery depicts a partially exposed low- level circulation with this low. Scattered moderate to strong convection is occurring within 120 nm of the low in the northeast quadrant. This low has a low potential for development over the next few days as it tracks westward to west- northwestward. A broad area of low pressure has developed several hundred miles south of the southern tip of the Baja California peninsula. Associated showers and thunderstorms are currently disorganized, and are depicted as the scattered moderate to isolated strong type intensity from 11N to 13N between 110W and 113w. Some gradual development of this disturbance will be possible over the next several days while it moves slowly northward. However, upper-level winds are expected to become unfavorable for any further development of this system by Sunday and Monday. The latest Tropical Weather Outlook gives this system a medium chance of tropical cyclone formation through 5 days. $$ Aguirre