{"msg": "448\nAXPZ20 KNHC 190400\nTWDEP \nTropical Weather Discussion\nNWS National Hurricane Center Miami FL\n0405 UTC Sat Sep 19 2026\nTropical Weather Discussion for the eastern Pacific Ocean from\n03.4S to 30N, east of 120W including the Gulf of California, and\nfrom the Equator to 30N, between 120W and 140W. The following\ninformation is based on satellite imagery, weather observations,\nradar, and meteorological analysis.\nBased on 0000 UTC surface analysis and satellite imagery through\n0350 UTC.\n...SPECIAL FEATURES...\nWestern East Pacific: Low pressure, Invest EP98, is centered near\n11N118W with a pressure of 1009 mb. This feature is part of a rather \nbroad area of cyclonic circulation. Satellite imagery exhibits \nscattered moderate to isolated strong convection from 05N to 17N\nbetween 115W and 125W. Environmental conditions are conducive \nfor development, and a tropical depression is likely to form this\nweekend as it moves westward at 10 to 15 mph across the western \nEast Pacific. The low has a high chance of tropical cyclone \nformation through the next 48 hours and the next 7 days.\nSouth of Southwestern Mexico: A tropical wave, Invest EP99, has its \naxis extending from near 18N107W to 04N107W, with low pressure \nof 1009 mb, near 08N106W. This feature is part of a broad area \nlow pressure that is located about 700 nautical miles south- \nsouthwest of the southwestern coast of Mexico. Satellite imagery \ndepicts scattered moderate to isolated strong convection from \n05N to 15N between 100W and 110W. Environmental conditions are \nconducive for development, and a tropical depression is likely to\nform late this weekend or early next week while it moves \ngenerally northward off the coast of southwestern Mexico. This \nsystem has a medium chance of tropical cyclone formation through \nthe next 48 hours and a high chance of development within the \nnext 7 days.\nPlease refer to the latest NHC Tropical Weather Outlook at \nwebsite: www.hurricanes.gov for more details on these Invests.\n...TROPICAL WAVES...\nA tropical wave in the western Caribbean Sea with axis near 81W \nextends southward across Panama and its offshore waters. It is \nmoving westward near 15 kt. Numerous moderate to strong \nconvection is from 02N to 10N between 77W and 85W.\n...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...\nThe monsoon trough axis extends from 08N83W to 08N100W to \n12N120W to 17N137W to 15N140W. Scattered moderate to isolated \nstrong convection is from 03N to 13N between 90W and 100W, and\nfrom 09N to 21N between 125W and 135W. \n...OFFSHORE WATERS WITHIN 250 NM OF MEXICO...\nThe pressure gradient between a ridge over the Gulf of America \nand the eastern extension of the Pacific monsoon is supporting \nfresh to strong N gap winds across the Gulf of Tehuantepec. Seas\nwith these winds are 6 to 8 ft. Scattered showers are over the \noffshore waters between Chiapas and Oaxaca due to a broad area of\nlow pressure and the monsoon south of the region. The gradient \nrelated to high pressure west of the Baja California offshores\nand low pressure along western Mexico is supporting fresh to\nlocally strong NW winds N of Cabo San Lazaro. Moderate or weaker\nwinds are elsewhere along with moderate seas, except for slight \nseas in the Gulf of California. \nFor the forecast, winds will pulse to fresh to strong speeds in \nthe Gulf of Tehuantepec tonight becoming moderate N to NE winds \nSat afternoon. Fresh to strong NW winds offshore Baja California\nwill diminish Sat afternoon. Northwest winds over these waters \nare expected to briefly reach fresh speeds Mon night into Tue. \nOtherwise, the environmental conditions of Invest EP99, near \n08N106W, are conducive for development and a tropical depression\nis likely to form late this weekend or early next week while it \nmoves generally northward off the coast of southwestern \nMexico. Regardless of development, this system is forecast to \nbring fresh to strong winds and moderate to rough seas to the \nMichoacan and Jalisco offshores Tue night into the middle part of\nnext week.\n...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, \nAND WITHIN 750 NM OF ECUADOR...\nModerate to fresh NE to E winds are across the Gulf of Papagayo \nextending downstream to near 88W. Moderate or weaker winds \nprevail elsewhere, except for strong to gusty winds likely\nongoing across the W Panama and Costa Rica offshores due to\nstrong convective activity associated with a tropical wave. Seas\nover the offshore waters are of moderate state due to a long- \nperiod southwest swell.\nFor the forecast, the pressure gradient between the ridge north \nof the area and the eastern Pacific monsoon will support pulsing \nfresh to occasionally strong easterly winds and moderate to rough\nseas across the Papagayo region into early Sat, then pulsing to \nmoderate to fresh speeds through early Sun. Moderate winds and \nseas will prevail elsewhere.\n...REMAINDER OF THE AREA...\nThe remnant 1008 mb low of former Tropical Depression Fifteen-E \nis located near 17N137W. A tight gradient between the low and \nhigh pressure of 1024 mb to its north is bringing fresh to \nstrong northeast to east winds over the waters from 16N to 26N \nwest of 124W. Seas are 6 to 9 ft within this area of winds. \nSatellite imagery shows scattered moderate isolated strong \nconvection from 10N to 21N between 126W and 135W. Elsewhere, \nwinds are moderate or weaker for the most part and seas are of \nmoderate state, except for rough state seas in the vicinity of \nInvest EP98. \nFor the forecast, see the Special Features section. Otherwise, \nenvironmental conditions appear conducive for some development \nof this system next week as it moves westward to west-\nsouthwestward, and a tropical depression could form well to the \nsouth or southeast of the Hawaiian Islands by the middle to \nlatter part of next week.\n", "title": "Eastern Pacific Tropical Weather Discussion", "id": "1211498597182799874", "issued": "2026-09-19T04:05:00Z", "wmo": "AXPZ20", "source": "NOAA/NWS National Hurricane Center, received via the National Weather Wire Service", "page": "https://hurricane.terrapin.com/text/1211498597182799874"}