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Tropical Weather Discussion


Issued Active alert

Start Time

Wed 01/20/2021 11:05 PM EST

End Time

Thu 01/21/2021 05:05 AM EST



Full Alert Message

Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Thu Jan 21 2021 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 0000 UTC surface analysis and satellite imagery through 0300 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 08N78W to 06N87W to 08N110W to 06N119W. The ITCZ continues from 06N119W to 05N123W to beyond 07N140W. Scattered moderate isolated strong convection is noted from 07N to 10N between 107W and 111W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... An occluded 1010 mb low pressure area is centered near 29N117.5W. The low is expected to drift eastward and weaken tonight, with winds on both sides of the Baja California peninsula diminishing steadily. The low will move inland across Baja California Norte Thu, with a significant improvement in marine conditions likely to occur. NW swell propagating through the Baja waters will maintain seas in excess of 8 ft through Thu. Strong northerly winds are expected to continue across the Gulf of Tehuantepec region through Fri with downstream seas peaking at 10 ft each morning. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Fresh to strong gap winds will pulse across the Papagayo region at night through Sun. Moderate northerly winds will pulse to fresh across the Gulf of Panama each evening and night through Fri then remain moderate through early next week. Gentle to moderate winds are expected elsewhere. Seas will build slightly from in mixed long period SW and W swell through early Fri. REMAINDER OF THE AREA... An occluded 1010 mb low pressure area centered near 29N117.5W will drift eastward and rapidly weaken tonight. High pressure NW of the area extends a ridge into the northwest forecast waters. The pressure gradient between the ridge and lower pressures near the convergence zone is supporting moderate to fresh trade winds north of the convergence zone to near 16N west of 125W. Seas in this area are in the 8-10 ft range in a mix of NW swell and NE to E wind waves, which is expected to persist through Thu. NW swell continues moving southeast across the open waters of the northeast Pacific with seas up to 12 ft west of the surface low near 29N117.5W. NW swell will maintain seas greater than 8 ft over much of the forecast waters west of 115W through Thu. Seas will subside across the open waters by the end of the week, with the next significant north to northwest swell event expected to arrive this weekend.