000 AXPZ20 KNHC 101559 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1331 UTC Sun Nov 10 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. ...SPECIAL FEATURE... Gulf of Tehuantepec Gale Warning: A ridge across the eastern slopes of the Sierra Madre mountains in Mexico and the Gulf of Mexico continues to support minimal gale force northerly winds over the Tehuantepec region, with seas up to 13 ft. Winds are forecast to diminish below gale force early this afternoon as the ridge begins to weaken. However, fresh to strong northerly winds are expected to persist across the Tehuantepec region through Tue, particularly during the overnight and early morning hours. Then, a strong cold front moving across the western Gulf of Mexico will bring back northerly gale force winds by Tue evening. This new gap wind event is forecast to peak Tue night into Wed with winds reaching 30-40 kt and seas building up to 18 or 19 ft. See the latest NWS High Seas Forecast under AWIPS/WMO headers HSFEP2/FZPN03 KNHC or at website https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for further details. ...TROPICAL WAVES... A tropical wave is along 85W N of 06N, moving W at around 10 kt. A cluster of moderate to isolated strong convection is near the southern end of wave axis N of 07N between 83W and 85W. A tropical wave is along 97W from 04N to 13N, moving W at around 10 kt. Scattered moderate convection is from 06N to 09N between 94W and 101W. A tropical wave is added along 118W from 04N to 14N. Scattered moderate convection is from 08N to 14N between 112W and 120W, and from 06N to 09N between 120W and 123W. A tropical wave is along 131W from 05N to 14N, moving W at 15 kt. Scattered moderate convection is from 07N to 09N between 129W and 131W. A tropical wave is along 139W from 05N to 14N, moving W at 10 to 15 kt. Scattered moderate convection is from 05N to 10N between w of 132W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from northern Colombia near 10N74W to 07N90W to 10N105W. The ITCZ continues from 09N105W to 07N125W to 09N140W. Aside from the convection associated with the tropical waves described above, scattered moderate isolated strong convection is N of 06N between 78W and 82W, including the Gulf of Panama, and within 90 nm N of the monsoon trough between 88W and 91W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please, see Special Features section for details about gale force winds in the Gulf of Tehunatepec. Elsewhere, a ridge dominates the offshore forecast waters west of Baja California, supporting gentle to moderate northerly winds, and seas generally under 6 ft. Little change is expected through Tue. A strong high pressure building across Mexico in the wake of a cold front moving across the Gulf of Mexico will result in a strong pressure gradient over N and central Mexico Mon into Tue. This will produce fresh to strong NW to N winds near the entrance of the Gulf of California on Mon, with these winds spreading south across the waters between Cabo Corriente and Los Cabos by Tue, and farther south to near 17N between 105W and 109W by late Tue. Seas are forecast to build to 9 or 10 ft with these winds. Over the Gulf of California, light to gentle variable winds will prevail most of the forecast period, with the exception of moderate to fresh NW to N winds over the southern part of the Gulf tonight and Mon. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh to occasionally strong offshore winds will prevail across the Gulf of Papagayo region through early Mon. Farther south, mainly gentle to moderate S-SW monsoonal flow will continue across the offshore forecast waters of Costa Rica, Panama, Colombia, and Ecuador through the middle of the week. REMAINDER OF THE AREA... A surface ridge extends from 1025 mb high pressure near 35N130W to near the Revillagigedo Islands. The pressure gradient between the ridge and lower pressure in the vicinity of the ITCZ is supporting mainly moderate to fresh NE trades N of the ITCZ to about 21N and west of 120W with seas of 8 to 9 ft. These seas will gradually subside below 8 ft by Tue afternoon. A cold front will reach the far NW waters Mon night and extends from 30N134W to 25N140W by late Tue. Winds of 20 kt or less and seas of 8 to 9 ft in NW swell will follow the front. A set of long period NW swell, with a leading edge period of 20 to 21 seconds, is forecast to enter the NW waters on Thu, building seas up to 13 or 14 ft by Thu night. $$ GR