000 AXPZ20 KNHC 250948 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 705 UTC Mon Mar 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 0600 UTC surface analysis and satellite imagery through 0845 UTC. ...SPECIAL FEATURES... Gulf of Tehuantepec Gale Warning: A strong N to S pressure gradient is expected to develop across southern Mexico by tonight as high pressure builds across the western Gulf of Mexico. This will support strengthening gap winds funneling through the Chivela Pass with winds likely reaching gale force by late tonight. N to NE winds are expected to continue pulsing to gale force Tue through Thu with winds nearing strong gale force during the late night and early morning hours Tue night through Thu morning. Seas will peak around 16 ft Wed morning. Gales will wind down Thu morning, then winds will become light and variable over the Gulf of tehuantepec by Fri morning as strong high pres over the Gulf of mexico shifts E. NE swell generated by this event will propagate well downstream beyond 100W. 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 specific marine details related to this event. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A trough extends from the coast of Colombia near 06N77W to 05N86W, where satellite-derived wind data from Sun evening indicated that the trough transitions to the ITCZ. The ITCZ continues to 04N100W to 02N118W to 05N137W to beyond 05N140W. Scattered moderate and isolated strong convection is found from 02N to 08N W of 135W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Gulf of Tehuantepec: Please refer to the Special Features section above for more information on the Gale Warning currently in effect. Gulf of California: Relatively tranquil conditions will prevail through midweek with winds remaining less than 15 kt and seas in the 1-3 ft range. The pressure gradient between high pressure of 1023 mb centered to the northwest of Baja California Norte at 31N121W and lower pressure over interior Mexico will continue to generate moderate to fresh winds over the offshore waters W of the Baja Peninsula through Thu. Wave heights peaking to around 11 over the northern offshore waters will only subside slightly through early Mon as the swell continues to propagate SE to reach as far S as the Revillagigedo Islands this morning. The swell will gradually decay through midweek which will allow seas to subside below 8 ft across most of the area by Wed. Looking ahead, another high pressure system building E towards the region could support fresh to strong NW to N winds W of Baja California Norte Thu through Fri night. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Strong to near gale force NE to E winds will prevail over the Gulf of Papagayo through Fri night. The strongest winds will occur during the late night and early morning hours in conjunction with nocturnal drainage flow. Seas will build to 10 ft by Wed morning as NE swell propagate well downstream from the Gulf through Fri night. Gulf of Panama: Winds over the Gulf of Panama have diminished to moderate to fresh speeds. Winds will increase to strong speeds late Tue night as high pressure rebuilds over the Caribbean. Seas will build to 8-9 ft downstream of the Gulf Tue night through Thu night as SW swell mixed with the NE wind waves. Between Ecuador and the Galapagos Islands, light to moderate winds with 4-6 ft seas will prevail through midweek. Seas in this region will build 1 to 2 feet during the second half of the week in response to the arrival of long period SW swell. REMAINDER OF THE AREA... ...Northwest Swell a Primary Concern for the Most of the Discussion area during the next few days... A weakening frontal trough extends from near 32N130W to 25N138W. On its heels, a cold front entering the far NW waters stretches from near 32N132W to pass W of the discussion area at 26N140W. The most significant marine impact from this new cold front will be that it will introduce a reinforcing set of long-period NW swell into the NW waters today. Yet another cold front entering the far NW waters Tue night will usher in even more NW swell. This front will weaken as it crosses the waters W of Baja California Norte. An enhanced pressure gradient between high pressure north of the region and the ITCZ is supporting fresh to locally strong NE to E trade winds from roughly 07N to 13N west of 120W. These winds are expected to diminish to fresh speeds by this evening as high pressure currently centered near 31N121W shifts ESE and weakens. Elsewhere, NW swell propagating across the high seas domain is maintaining seas of 8 ft or greater over the waters generally to the north of 02N and west of about 111W. NE swell generated by gap winds over the Gulfs of Papagayo and Tehuantepec will merge with NW swell and long period cross-equatorial S to SW swell Tue through Fri. This will result in a large swath of 8 to 10 ft seas spanning an area from the Equator to 15N and extending westward from near 90W to beyond 140W during this time frame. $$ CAM