000 AXPZ20 KNHC 071520 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1520 UTC Sat Mar 7 2020 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 FEATURES... Gulf of Tehuantepec Gale Warning: Strong gale force winds continue across the Gulf of Tehuantepec this morning as high pressure over eastern Mexico maintains an enhanced pressure gradient across the Isthmus of Tehuantepec. Scatterometer data from overnight showed 35-45 kt winds over and well downstream of the Gulf. Significant wave heights were analyzed to 20 ft this morning, and seas 12 ft or greater in NE swell extend as far as 09N-10N based on overnight altimeter data. Gales will persist through Mon morning, then briefly diminish before pulsing to gale force Mon night and possibly Tue night as well. Please read the latest High Seas Forecast issued by the National Hurricane Center under AWIPS/WMO headers FZPN03 KNHC/HSFEP2 or at website https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for further details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 05N83W to 03N95W. The ITCZ extends from 03N95W to 03N110W to 07N127W, then continues from 08N133W to 07N140W. A second ITCZ is analyzed from 03S85W to 03S104W. Scattered moderate convection is noted within 90 nm of the trough east of 91W, and within 120 nm of the ITCZ west of 133W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Please see the Special Features section above for details on a gale warning in the Tehuantepec region. Weak high pressure is centered offshore of Baja California near 27N124W this morning. Moderate to locally fresh southerly winds are occurring over the northern Gulf of California. Elsewhere outside of the Tehuantepec region, light to moderate winds prevail across the offshore waters under a weak pressure pattern. Strong SW gap winds will develop over the northern Gulf of California tonight ahead of an approaching cold front that will weaken and dissipate Sun. Early next week, low pressure centered NW of the region will track eastward and pull a frontal system toward the Baja offshore waters. Fresh to strong SE to S winds will develop offshore of Baja California Norte ahead of the cold front, which will likely cross the region through midweek while weakening. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: An enhanced pressure gradient across Central America and the NW Caribbean is producing strong to near gale force NE winds across the Papagayo region this morning. Strong winds will prevail across the region through the middle of next week, with winds pulsing to near gale force each night. Wave heights will peak around 9-11 ft downstream of the Gulf each morning for the next several days. Gulf of Panama: High pressure north of the area will maintain fresh to strong N to NE winds over and downstream of the Gulf of Panama for the next several days. Wave heights with these winds are expected to reach 8-10 ft well downstream of the Gulf. Elsewhere, large NW swell associated with the ongoing Gulf of Tehuantepec gap wind event is producing 10-16 ft seas offshore of Guatemala, with seas greater than 8 ft encompassing the waters off El Salvador in mixed NW and E swell. Seas well offshore will remain greater than 8 ft for the next several days in combined Tehuantepec and Papagayo swell, along with long period southerly swell that will reach the waters by Mon. REMAINDER OF THE AREA... Weak high pressure is centered offshore of Baja California near 27N124W this morning. A modest pressure gradient is supporting moderate NE to E trades north of the ITCZ, except for fresh winds noted west of 130W associated with a weak surface trough. Farther west, the tail end of a cold front extends into the northern waters from 30N130W to 26N137W. Overnight scatterometer data showed fresh to locally strong northerly winds behind the front, with 8-10 ft seas in northerly swell. This front will weaken through tonight and dissipate by early Sun. Mixed swell from the Tehuantepec and Papagayo gap wind events is propagating well downstream of the source regions, with seas 8 ft or greater roughly north of 05N between 90W and 105W. By Sun, 8 ft or greater seas will encompass the waters south of 12N between 90W and 110W as gap wind swell mixes with long period southerly swell propagating across the southern waters. A strong cold front will move across the NW portion Sun and Sun night in associated with low pressure that will move to near 31N133W by Mon morning. Strong to near gale force winds behind the front will build seas to 12-20 ft north of 24N and west of 130W on Mon. The low pressure is expected to track eastward through early next week and pull the cold front across the waters roughly north of 20N. Large NW swell associated with this system will propagate southward through the middle of next week. $$ Reinhart