We hope you have an umbrella handy. The National Weather Service reported that the tropical storm that formed off Mexico's coast has been upgraded to Hurricane Hilary — but San Diegan's aren't expected to feel the impact until later this weekend.

Hilary started to form on Wednesday and was classified as a Category 4 hurricane yesterday evening. It's expected to approach the Baja California peninsula tomorrow with decreased severity. As it moves north, it should continue to weaken. By the time it reaches San Diego, it could possibly still be classified as a tropical storm.

A projected map of Hurricane Hilary as of Thursday, Aug. 17. | Image via National Weather Service San Diego

Local weather impacts

For San Diego County, Hilary is expected to bring wind and showers starting tomorrow evening, with the heaviest rain Sunday into Monday.

As of yesterday, the National Weather Service anticipates the heaviest rain will be east of San Diego County — areas like Borrego Springs, Julian, and Mount Laguna could see up to 7 inches.
Coastal communities will see less rain, with downtown San Diego expected to receive 1.5 inches.
A flash flood warning is in effect from Saturday to Monday, with the greatest risk in the most eastern parts of San Diego county. The county has resources to prepare for flooding and a list of places to get sandbags.
Wind speeds are expected to increase Sunday and peak that evening into Monday morning — maximum gusts could exceed 50 mph early Monday. High surf is also expected along the coast both days.

Current predictions are based on the National Hurricane Center's forecast cone. This represents the probable track of the storm's center, but it allows for greater variance for events further in the future. Predictions may change before the storm reaches San Diego, so know where to find alerts.

Did you know? The last time a tropical storm reached land in San Diego was in 1939, and the only known hurricane to hit the county was in 1858.