000 AXPZ20 KNHC 152117 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Wed Jul 15 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 1800 UTC surface analysis and satellite imagery through 2115 UTC. ...TROPICAL WAVES... A tropical wave has its axis along 93W and north of 03N to far southeastern Mexico. It is moving westward at 10-15 kt. Scattered moderate to isolated strong convection is noted from 07N to 11N between the wave and 96W. A tropical wave has its axis along 105W from 03N to 18N is moving westward at 13 kt. Scattered moderate to isolated strong convection is observed from 07N to 13N between 102W-109W. Scattered moderate convection is east of the wave within 60 nm of 13N101W. A tropical wave has its axis along 126W from 03N to 19N, moving westward at about 10 kt. Scattered moderate convection is within 30 nm of 11N125W. A short-amplitude tropical wave has its axis along 134W from 02N to 14N, moving westward at 10 kt. Scattered showers and isolated thunderstorms are within 180 nm either side of the wave from 06N to 12N. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from a 1009 mb low over northwestern Colombia westward to across central Costa Rica and to 10N85W to 09N97W to 08N109W and northwestward to 12N117W to 12N124W and to 09N131W, where afternoon scatterometer data indicates that it transitions to the ITCZ and continues to 08N140W. Aside from the convection described above in association with the tropical waves, scattered moderate to isolated strong convection is within 120 nm south of the trough between 115W- 119W. Scattered moderate convection is within 30 nm of the trough between 86W-88W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... The pressure gradient related to a trough over Baja California is allowing for areas to the west to have fresh to locally strong northwest winds, which will continue through Fri. High pressure building into the Gulf of Mexico late Thu through Fri night will lead to strong gap winds in and downwind of the Gulf of Tehuantepec from Thu through Sun afternoon. While current guidance suggest near-gale conditions late on Thu and Fri nights, peak seas are anticipated to reach around 8 ft due to the limited area and duration of these gap winds. No significant long-period swell are expected in the Mexican offshore zones for at least the next several days. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh to strong northeast to east winds that occurred overnight last night and this morning in the Papagayo region have diminished to mainly fresh speeds. These winds will increase again to fresh to strong speeds tonight and diminish Thu afternoon, before pulsing up again to fresh to strong speeds late Thu night and diminishing to mainly fresh speeds on Fri afternoon and pulse back up to fresh to strong speeds late Fri night. Peak seas with these winds may reach 8 ft. Moderate to locally fresh monsoonal southwest winds will remain over the waters south of about 08N through through Fri night. No significant long-period swell is expected in the Central American and equatorial offshore zones for at least the next several days. REMAINDER OF THE AREA... A slightly tight gradient between a low-level trough and a ridge axis that extends southeastward into the north-central waters is allowing for fresh northeast winds to exist from 17N to 20N and between 122W and 127W. Seas of 5-6 ft are within this area of fresh winds. The trough is forecast to dissipate by early Thu. The earlier observed weak low pressure of 1013 mb that was analyzed near 23N139W has weakened further to a tough along 140W from 21N to 25N. The gradient between the trough and strong high pressure of 1032 mb that is situated well NNW of the area is keeping a shrinking area of strong northeast to east winds from 24N to 27N and west of 138W along with seas in the range of 8-10 ft. As the trough moves west of 140W through tonight, this will allow for the tight pressure gradient between it and high pressure ridging to its north to begin to relax. The strong east winds east will then response by diminishing into Thu. Seas up to 8 ft in decaying northeast to east swell will remain from 24N to 27N and west of 139W by late tonight, subsiding to less than 8 ft during Thu morning. Moderate to fresh south winds remain to the south of the monsoon trough between 115W and 135W. These winds are combining with some southeast swell resulting in combined seas of 8-10 ft. These seas will shift westward before diminishing Thu night. A weakening cold front or trough is forecast to move over the waters north of 25N from 125W to 140W Thu, ushering in fresh northeast winds and seas possibly in the range of 7-10 ft into early Sat. Convection associated with the tropical wave currently along 105W, as described above, has increased in coverage during the past 24 hours. Indications from global model guidance are that low pressure is likely to form from this wave in a few days as it moves west-northwest or northwestward across the central part of the basin. $$ Aguirre