Thunderstorms forecast: Little rain for Bay Area but lightning raises wildfire risk
Isolated thunderstorms are expected as early as Sunday afternoon along the California coastline, including parts of the Bay Area, but they won’t provide much relief from ongoing drought conditions and an increasingly active early wildfire season.
Heads up! A few thunderstorms are possible late Sunday into Monday. More updates to come as we fine tune potential, so keep up with forecast changes. Stay weather aware if you have outdoor plans and remember:
If thunder roars, go indoors! #cawx pic.twitter.com/exJIyH09h6
— NWS Bay Area
(@NWSBayArea) July 30, 2022
Meteorologists predict a weather system that’s dousing southwestern states with monsoon storms will make its way up the Central Coast to the northern Bay Area through Monday evening.
But thunderstorms in the Bay Area and elsewhere along the coast most likely won’t amount to much more than rumbling skies and heavy cloud cover, and not widespread heavy rainfall, according to the National Weather Service.
On the other hand, the thunderstorms do bring a chance of lightning to most affected regions, posing some threat of lightning-sparked wildfires in the drier inland areas.
“In these types of situations, the risks can be greater than the benefits,” said Jeff Lorber, a National Weather Service meteorologist, in an interview.
Why wouldn’t a thunderstorm — emphasis on “storm” — produce much rain? Lorber says it’s because of California’s summer climate, namely the warm, dry pockets of air below the atmosphere that evaporate most moisture before it can fall to the earth.
Summer storms earlier this week led to flooding in southwestern states such as Arizona and New Mexico, and even Las Vegas. But when they arrive in California, the thunderstorms are expected to create heavy rainfall for very brief periods and light drizzling the rest of the time.
Here's a look at today's forecast maximum temperatures across the Bay Area and Central Coast. Also, isolated thunderstorms look possible late Sunday into Monday across the region as well! Stay up-to-date with the latest information through the weekend. #CAwx #BayAreaWX pic.twitter.com/9NbvboHxoc
— NWS Bay Area
It is unwelcome news for Californians who are increasingly worried about persistent drought conditions. Earlier this week, the House of Representatives approved a wide-ranging legislation package aimed at aiding parts of the state that are especially affected by drought conditions and severe wildfires.
Some of California’s historically largest wildfires were sparked by lightning strikes, including the August Complex in 2020 that burned more than 1 million acres across several Northern California counties.
Lightning risk during this weekend’s thunderstorms is “limited” and not “elevated” or “significant,” according to the National Weather Service’s measurement scale. But that still doesn’t rule out the potential for wildfire.
“Even if it’s raining, the lightning could strike outside of the main rain areas and cause some risk,” Lorber said, “especially with such dry conditions in the interior parts of the Bay Area.”
On the bright side, the thunderstorms aren’t expected to create strong winds besides some scattered heavy gusts, Lorber said. Wind speeds are projected to be around normal, and the weather service has not issued an advisory in the Bay Area.
Official guidance advises residents to stay indoors when they hear thunder outside, in case there’s lightning accompanying it.
“The coastal fog in the Bay Area always helps,” he said. “We welcome any rainfall, of course, but we don’t welcome any risk of igniting a wildfire.”