000 AXPZ20 KNHC 110928 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Fri Aug 11 2023 Tropical Weather Discussion for the eastern Pacific Ocean from 03.4S to 30N, east of 120W including the Gulf of California, and from the Equator to 30N, between 120W and 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 0915 UTC. ...TROPICAL WAVES... A tropical wave (EP98) has its axis along 112W from 04N to 18N, moving westward at 10-15 kt. Satellite imagery shows a large a large area of disorganized scattered showers and thunderstorms several hundred nm south-southwest of the coast of southwestern Mexico, or roughly from 04N to 13N between 104W-115W. Environmental conditions appear conducive for gradual development of this system, and a tropical depression is likely to form late this weekend or early next week while it moves westward across the central portion of the basin. The latest Tropical Weather Outlook gives this system a low chance of tropical cyclone formation through 48 hours. A tropical wave has its axis along 131W from 04N to 17N. It is moving westward at about 15 kt. Some disorganized scattered moderate convection is noted within 180 east of this wave from 06N to 13N, and within 60 nm west of the wave from 07N to 12N. Some slow development of this system is possible during the next several days while it moves westward across the far western portion of the basin and into the Central Pacific basin. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from northwest Colombia to across the Costa Rica/Panamanian border to 09N84W to 10N92W to 14N107W. The ITCZ extends from 10N114W to 10N122W to 09N129W, and also from 09N132W to beyond the area at 06N140W. Scattered moderate to isolated strong convection is seen from 03N to 08N between 87W-94W, from 07N to 09N between 95W-102W, within 120 nm south of the ITCZ between 132W-134W and within 60 nm north of the axis between 132W-133W. Scattered moderate convection is within 180 nm south of the ITCZ between 112W-115W, within 120 nm south of the ITCZ between 133W-136W and within 60 nm south of the ITCZ between 78W-80W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... High pressure is located well northwest of the area, with a ridge that extends east-southeastward to near 21N115W. The associated weak pressure gradient between the ridge and relatively lower pressure over Baja California and northwest Mexico is producing moderate or weaker northwest winds, but higher speeds of moderate to fresh are within about 60-90 nm offshore the coasts from Punta Eugenia to Cabo San Lucas. Seas are in the general range of 4-6 ft. Inside the Gulf of California, gentle to moderate southeast winds are south of 30N, while fresh to strong SW winds prevail across northern part of the Gulf, where seas are 4-5 ft. Seas are generally 2-3 ft over the Gulf, except for slightly higher seas of 3-4 ft near the entrance. For the forecast, moderate to fresh NW winds offshore the coast of Baja California from Punta Eugenia to Cabo San Lucas will continue through early next week. Fresh to strong southwest winds over the northern Gulf of California will diminish to moderate to fresh early this morning. Fresh to locally strong N winds may pulse in the Gulf of Tehuantepec Sat night, Sun night and Mon night. Looking ahead, an area of low pressure is forecast to form offshore of Central America in a few days. Environmental conditions are expected to be conducive for gradual development of this system, and a tropical depression could form during the early or middle part of next week while it moves generally west- northwestward, roughly parallel to the coast of southern Mexico. ...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Moderate east gap winds are occurring across the Gulf of Papagayo region, with moderate or weaker east to southeast winds are elsewhere north of 10N and gentle to moderate southwest to west winds are south of 10N. Seas are 3-5 ft in southerly swell, except 1-3 ft in the Gulf of Panama, and offshore Colombia. For the forecast, offshore winds will pulse to moderate to fresh at night into the early morning hours in the Papagayo region through early next week. Elsewhere, gentle to moderate winds and mainly moderate seas will prevail through Sun night. Looking ahead, an area of low pressure is forecast to form offshore of Central America in a few days. Environmental conditions are expected to be conducive for gradual development of this system, and a tropical depression could form during the early or middle part of next week while it moves generally west-northwestward, roughly parallel to the coast of southern Mexico. Expect increasing winds, seas, and unsettled weather during this time. ...REMAINDER OF THE AREA... A very weak pressure gradient remains west about 110W. A ridge extends east-southeastward from high pressure that is centered well northwest of the Hawaiian Islands to near 21N118W. Light to gentle winds are under the influence of the ridge. The pressure gradient between this ridge and lower pressure in the vicinity of the monsoon trough is producing gentle to moderate northeast trade winds from 11N to 23N and west of 120W. Moderate to locally fresh southerly winds are present from 03N to 10N between 104W-108W as noted in an overnight ASCAT pass. These winds are mainly be driven by the gradient that was created by convection that is within and near this area south of the monsoon trough. Seas over this area are generally 5-7 ft in south to southwest swell across the open waters. For the forecast, fairly tranquil conditions are forecast across the open waters through the end of the week and into the upcoming weekend as a weak pressure pattern dominates the region. Low pressure is likely to develop near or along the tropical wave that is along 110W during the next several days. Please see the Tropical Waves section for more details. $$ Aguirre