Tropical Weather Discussion

Full Alert Message

Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Sun Jun 28 2026 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 0830 UTC. ...TROPICAL WAVES... A tropical wave axis is along 92W north of 02N to W Guatemala, moving westward at 10 to 15 kt. Scattered moderate convection is noted from 03N to 10N between 89W and 96W. A tropical wave has its axis along 121W from 03N to 20N, moving westward at around 15 kt. Scattered moderate convection is noted from 04N to 16N between 114W and 128W. Scatterometer data depicted fresh to strong east to southeast winds east of the wave axis to near 110W. Seas are up to 9 ft with these winds. A tropical wave axis is analyzed along 137W from 12N to 23N, moving W at 10 to 15 kt. No significant convection is noted at this time. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 1007 mb low pressure in northwest Colombia to 07N78W to 07N91W. The ITCZ continues from 07N92W to 10N119W, then resumes W of a tropical wave near 09N122W to 07N140W. Aside from the convection related to the tropical waves described above, scattered moderate convection is noted within 200 nm on either side of the ITCZ. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... The pressure difference between high pressure ridging over the Gulf of America and lower pressure in southeastern Mexico, southward to the monsoon trough over the eastern Pacific is supporting fresh to strong gap winds in the Gulf of Tehuantepec. Seas up to 8 ft prevail with these winds. In the Gulf of California, moderate to fresh south to southwest winds are over the northern portion east of 114W due to a tight pressure gradient in the area. Seas are 2 to 4 ft over the Gulf, except for seas of 3 to 5 ft in the southern portion. Light to gentle winds are elsewhere over the Mexican offshore waters along with seas of 4 to 6 ft in long- period south to southwest swell. For the forecast, the fresh to strong north to northeast gap winds will continue pulsing in the Gulf of Tehuantepec region through Mon morning. Elsewhere, winds and seas across the Mexican offshore waters should be calm through early week. Northwest swell with seas to 8 ft is expected to move into the far northern waters off Baja California Norte beginning early Mon, and linger into Tue afternoon. ....OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh to near-gale northeast gap winds are across the Gulf of Papagayo and off the southern coast of Nicaragua. Latest altimeter satellite data shows seas of 8 to 9 ft downstream of these winds, from 09N to 11N between 87W and 90W. Moderate or weaker winds are elsewhere. Seas are 6 to 8 ft in long-period southerly swell over the equatorial waters as detected by multiple altimeter satellite data passes, and 5 to 6 ft in southwest swell over the remainder of the offshore waters. For the forecast, fresh to near-gale gap winds and rough seas will prevail across the Gulf of Papagayo through early Tue. These conditions may spread as far west as 105W through tonight before diminishing. Farther south, large southerly swell moving into the equatorial waters will continue through early next week. ...REMAINDER OF THE AREA... Broad ridging dominates the remainder of the area north of 20N. The moderate pressure gradient between the ridge and lower pressure in the vicinity of the monsoon trough/ITCZ is resulting in moderate to fresh trade winds from 10N to 28N. Seas are 6 to 8 ft W of 112W due to the combination of long-period north to northeast swell with trade wind generated waves. To the south, SE swell is bringing seas to 10 ft S of 02N between 87W and 122W. Elsewhere, winds across the open Pacific waters are moderate or weaker. Seas are 6 to 8 ft in mixed north and southwest swell. For the forecast, the tropical wave near 121W is forecast to undergo possible gradual development during the next few days and a tropical depression could form around the middle of next week while the wave moves generally westward to west-northwestward. Environmental conditions are forecast to become less conducive for development by the second half of the week as the system moves over the western portion of the eastern North Pacific. Outside of this system, little change in winds are expected for the next several days. Large southerly swell moving through the far south-central waters is expected to begin to decay during the early part of the upcoming week.