{"msg": "687\nAXPZ20 KNHC 200706\nTWDEP \nTropical Weather Discussion\nNWS National Hurricane Center Miami FL\n1005 UTC Thu Aug 20 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 0600 UTC surface analysis and satellite imagery through\n0610 UTC.\n...SPECIAL FEATURES...\nCentral Pacific (EP90): An area of low pressure, Invest EP90, \nhas fully crossed over into the Central Pacific basin to the west\nof 140W, currently near 11N141W. While outer winds and seas \nstill extend just to the east of 140W into the discussion waters,\nwinds east of 140W are forecast to remain below warning \ncriteria. Please refer to the latest NHC Tropical Weather Outlook\nat website:\nhttps://www.nhc.noaa.gov/text/MIATWOEP.shtml for more details.\n...TROPICAL WAVES...\nThe axis of a tropical wave is just east of the area over\nportions of western Colombia and moving from the central to the\nwestern Caribbean Sea near 76W, moving westward at 15 to 20 kt.\nScattered moderate isolated strong convection is noted from 06N \nto 11N between 77W and 89W.\nThe axis of a tropical wave is near 96.5W from 01N to 17N just\nwest of the Gulf of Tehuantepec over portions of Oaxaca, or a \nfew hundred nautical miles south of the coast of southern Mexico,\nis moving westward at 15 to 20 kt. Scattered to numerous \nmoderate to strong convection is noted from 05N to 14N between \n89W and 98W. A tropical depression is likely to form this weekend\nwhile the system moves generally west-northwestward, remaining \nwell offshore of Mexico. This system has a low chance of tropical\ncyclone formation in the next 48 hours, and a high chance in the\nnext 7 days. Regardless of development, expect increasing winds \nand seas to impact the outer offshore waters of southwestern \nMexico. \nThe axis of a tropical wave is near 111W from 01N to 16N, moving\nwestward at around 15 to 20 kt. A broad area of low pressure \nassociated with this tropical wave near 08N111W is producing \ndisorganized showers and thunderstorms several hundred nautical \nmiles south of the southern tip of the Baja California Peninsula.\nScattered to numerous moderate to strong convection is noted \nfrom 05N to 12N between 106W and 115W. Winds are currently fresh \nwith locally rough seas there. Environmental conditions are \nforecast to be marginally favorable for gradual development over \nthe weekend as the system moves westward or west- northwestward \nat 5 to 10 kt.\nPlease refer to the latest NHC Tropical Weather Outlook at \nwebsite:\nhttps://www.nhc.noaa.gov/text/MIATWOEP.shtml for more details on\nboth systems.\n...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...\nThe monsoon trough extends from 1007 mb low pressure over\nnorthern Colombia at 11N75W to 08.5N90W to 1009 mb low pressure\nnear 08N111W to 07N125W to 10N140W. Other than the convection \ndescribed above with three tropical waves, scattered moderate \nisolated strong convection is noted from 04N to 11N between 129W \nand 133W. Scattered moderate convection is noted from 10N to 17N \nbetween 130W and 140W, mainly related to Invest EP90 which has \ncrossed over into the Central Pacific basin.\n...OFFSHORE WATERS WITHIN 250 NM OF MEXICO...\nPlease refer to the Tropical Waves section above for information\non a tropical wave that has a potential for tropical development\noffshore Mexico this upcoming weekend, and for related\nconvection. \nA tight pressure gradient continues over the Gulf of Tehuantepec\nwhere the northern portion of a tropical wave is just passing \nby, and is producing strong N to NE gap winds in the Gulf. Recent\nASCAT scatterometer data confirmed these winds. Resultant seas \nof 5 to locally 8 ft. Across the remainder of the offshore waters\nof Mexico, typical ridging has been disrupted by a surface trough\nfrom Baja California Norte to the southwest resulting in a rather\nweak pressure gradient across the region and mainly light to\ngentle winds, except moderate from near Cabo Corrientes up the\ncoast toward the entrance of the Gulf of California as seen by\nthe same ASCAT data. Seas are 4 to 6 ft across the waters away\nfrom the Gulf of Tehuantepec, and 1 to 3 ft inside the Gulf of \nCalifornia. A thunderstorm complex is evident on conventional\ninfrared satellite imagery near the boast of western Oaxaca and\nGuerrero.\nFor the forecast, northerly gap winds will continue to pulse to \nstrong north winds over the Gulf of Tehuantepec during the\novernight into the early morning hours through the next several \ndays, with seas occasionally building to rough. Low pressure \nacross Baja California will sustain a southerly wind flow across \nthe Gulf of California waters. Winds may freshen across the Gulf\nof California Sat night through Sun night, and also freshen\nnearshore Baja California Fri night through Sat as the pressure\ngradient tightens a bit. Looking ahead, winds and seas are \nexpected to build across the outer offshore waters of \nsouthwestern Mexico by tonight into early next week in \nassociation with a developing area of low pressure moving by just \noutside of the offshore waters.\n...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, \nAND WITHIN 750 NM OF ECUADOR...\nRefer to the Tropical Waves section above for details on any\nconvection.\nRecent ASCAT scatterometer passes missed the immediate Gulf of\nPapagayo where fresh to strong easterly gap winds are likely\noccurring, however they did measure moderate to fresh easterly\nwinds well downwind across the outer offshore waters of El\nSalvador and Guatemala to the south of 12.5N, with seas of 5 to\nlocally 8 ft from Offshore Gulf of Papagayo to near 11N96W. \nMainly moderate or weaker winds are found elsewhere, locally \nfresh near the border of Peru an Ecuador close to the entrance to\nthe Gulf of Guayaquil. Seas are 4 to 7 ft across the remainder of\nthe waters north of the Equator, and 6 to 8 ft south of the\nEquator, except to 9 ft near the Gulf of Guayaquil as measured by\na recent Sentinel-3B altimeter pass. Some isolated to widely\nscattered showers and thunderstorms are over the waters south of\nPanama to off Costa Rica, as well as offshore Guatemala due to\nthe passing tropical wave there, described more above.\nFor the forecast, the pressure gradient between high pressure \nover the northwestern Caribbean and relatively lower pressure \nover Central America will lead to fresh NE to E gap winds pulsing\nto strong winds over the Papagayo region each evening and night \nthrough the early next week, resulting in rough seas at times. \nModerate to fresh winds extending well downwind of Papagayo will \nimpact the outer waters offshore of El Salvador and Guatemala \nthrough at least early next week. Any lingering moderate to \nlocally fresh southerly winds south of the monsoon trough and \nacross the Galapagos waters will gradually diminish today. Mainly\nmoderate seas will prevail away from the Gulf of Papagayo area\nthrough the next several days, dominated by long period southerly\nswells. Seas may be locally rough south of the Equator early\ntoday.\n...REMAINDER OF THE AREA...\nPlease see the Special Features section and the Tropical Waves \nsection above for information on systems that have the potential\nfor tropical cyclone formation, and any associated convection \ncurrently present leading to locally higher winds and seas.\nHigh pressure across the NE Pacific extends a ridge south- \nsoutheastward into the regional waters to just northwest of the \nRevillagigedo Islands, however it is now disrupted by a surface \ntrough analyzed from 30N135W to 23N140W which was nicely evident\nin a recent ASCAT scatterometer pass. Outer fresh to strong \nwinds and 8 to 11 ft seas associated with Invest EP90 now west of\nthe area in the Central Pacific basin are impacting the waters \nfrom 11N to 16N between 137W and 140W. Moderate to locally fresh \ntrades are found elsewhere from 14N to 23N between 128W and 140W.\nModerate to locally fresh winds are found south of 06N to the \neast of 120W and south of 02N to the west of 120W. Rough seas \nover the southern waters are decaying, now over the waters south \nof 02N and east of 130W, up to 9 ft south of the Equator and east\nof 110W.\nFor the forecast, regardless of tropical development, the \nfeatures described above will bring some increasing winds and \nseas to area waters south of 25N, as they move south of the \ncurrent ridge in place. Away from these features, little change \nis expected in marine weather through the next several days, \nexcept for the rough seas over the southern waters which are \nforecast to fully subside to moderate levels by the start of the\nweekend.\n", "title": "Eastern Pacific Tropical Weather Discussion", "id": "1203041678791966723", "issued": "2026-08-20T10:05:00Z", "wmo": "AXPZ20", "source": "NOAA/NWS National Hurricane Center, received via the National Weather Wire Service", "page": "https://hurricane.terrapin.com/text/1203041678791966723"}