Remnants of Hurricane Hilary arriving in Sacramento

Updated Aug. 21, 9:22 a.m.

Remnants of the storm formerly known as Hurricane Hilary are hitting the Sacramento region Monday, bringing rain and wind to Northern California.

"For today we're looking probably less than a quarter inch for most of the Central Valley areas," said David Rowe with the National Weather Service in Sacramento. "There will be some thunderstorms popping up, especially in the valley from about Sacramento southward into Stockton, Modesto areas from mid-afternoon into the early evening and those could have some heavier rain with them along with some small hail and gusty winds."

Light rain associated with the remnants of #Hilary continues to spread north across the northern #SierraNevada while showers have developed in the Sacramento and Stockton areas early this morning. Watch for wet roadways during the morning commute! #CAwx pic.twitter.com/mNw5owhVfM

— NWS Sacramento (@NWSSacramento) August 21, 2023

The system, now a post-tropical storm, hit landfall over the weekend, with the center passing over Los Angeles around 8 p.m. Sunday. According to LAist, the storm downed trees, flooded roads and left more than 8,000 people without power in the city of L.A. Governor Gavin Newsom proclaimed a state of emergency for much of Southern California.

The storm is starting to break down as it heads northeast to Nevada, which is bringing rain and wind to Northern California as well. 

The Sacramento area will see partly sunny skies today with highs in the mid-80s, though with winds up to 30 mph in some areas. The 90-degree temperatures return Tuesday and the hot weather returns Wednesday and Thursday with highs in the upper 90s.  

"Looks like we'll probably be dry from Tuesday on and temperatures will warm back above average Wednesday, Thursday and then we have another low-pressure system moving towards the Pacific northwest late in the week which should introduce the return of the Delta breeze for us and help to cool temperatures back down," Rowe said.

Paul Ullrich, a regional and global climate modeling expert at UC Davis, said hurricanes typically draw energy from warm, sea surface temperatures. By the time they hit land, they’ll start to lose strength — like a car running out of gas. 

“As soon as it hits land, that hurricane is going to start de-intensifying,” he said. “It's still going to keep rolling, but it's not going to be as strong and it's going to weaken pretty rapidly.” 

He said a hurricane like this one is the result of warmer-than-usual ocean temperatures. Those higher temperatures are likely linked to current El Niño weather patterns and global, gradual ocean warming brought on by climate change. 

Courtney Carpenter, warning coordination meteorologist for the National Weather Service in Sacramento, said this precipitation is unusual for the region in August. But overall, she described the coming rain as mostly “beneficial wetting” for the region.

Although it’s not unusual for hurricanes to form off the western coast of Mexico, Ullrich said it’s not often that they impact California. He said the last time the state saw a hurricane make landfall was in Long Beach, in 1939. But he said this will likely change. 

“These warmer temperatures are likely to persist and be intensified by global warming,” Ullrich said. “This may be a storm that we can use to basically plan and adapt — assess our vulnerability for the future.”