Puerto Vallarta, Jalisco, August 20, 2026 – The chance of a tropical depression forming south-southwest of Mexico has risen to 80 percent through the next seven days, but the system is expected to remain well offshore as it moves west-northwest. Puerto Vallarta’s more immediate concern Thursday is heavy rain from a separate weather pattern already affecting western Jalisco.
The National Hurricane Center’s Thursday morning outlook placed the disturbance several hundred miles south of southern Mexico, where a tropical wave was producing disorganized showers and thunderstorms.
Conditions could support gradual development, with a tropical depression likely during the weekend. The chance of formation remains only 20 percent through the next 48 hours before increasing to 80 percent across the full seven-day period.
That 80 percent figure measures the likelihood that the disturbance will organize into a tropical cyclone somewhere within the forecast area. It does not represent an 80 percent chance of landfall or impact in Puerto Vallarta.
The projected west-northwest movement would keep the system well offshore of Mexico. Puerto Vallarta was not under a tropical storm or hurricane watch Thursday morning.
The development odds have increased since Sunday, when PVDN reported a 50 percent seven-day chance connected to the southern Mexico formation area. The change indicates that atmospheric and ocean conditions have become more favorable, even though the expected movement remains away from the coast.
Western Jalisco faces a separate and more immediate weather problem. The Servicio Meteorológico Nacional’s 6 a.m. forecast placed the western part of the state under a risk of localized rainfall totals between 75 and 150 millimeters Thursday.
Federal forecasters linked that rain to low-pressure channels across Mexico, an upper-level cyclonic circulation and Tropical Wave 29 moving across the country’s south. The developing Pacific disturbance was not listed as the cause of Thursday’s Jalisco rainfall.
The heaviest storms could produce lightning, localized flooding, rising rivers and streams, landslides and reduced visibility. The rainfall range applies to isolated parts of western Jalisco rather than every community receiving the same amount.
In Puerto Vallarta, Thursday’s local forecast calls for hot and humid conditions, with rain and thunderstorm chances increasing later in the day. Streets that drain slowly, low crossings and routes near streams could become difficult during a concentrated downpour.
The next meaningful change in the offshore disturbance would be the formation of a defined low-pressure center or tropical depression. Until then, Puerto Vallarta’s practical weather risk remains the rainfall already forecast across western Jalisco.
