Bay Area weather: Heat wave may break some record temperatures this week

On the heels of the last storm of the winter, which wetted Bay Area roads and coated Sierra Nevada ski slopes with snow over the weekend, a heat wave is expected to grip the region this week and flirt with breaking a few temperature records.

A large ridge of high pressure building off the coast is expected to move inland and usher in warmer conditions into the 70s and 80s for Tuesday and Wednesday, according to the National Weather Service. The heat wave, bolstered with offshore flow, could break some record temperatures Tuesday in the North Bay and on the Peninsula. High marks of 84 degrees set in Santa Rosa in 1926 and 75 degrees in San Francisco, passing the 1970 record of 73 degrees, are possible.

Onshore flow is expected to cool down conditions into the mid-60s and mid-70s by Thursday.

“This isn’t a significant heat wave; we’re just going to get really warm for the early season,” said forecaster Cynthia Palmer. “If you work outside and you aren’t used to the heat, drink plenty of water and try to stay in the shade until your body starts to acclimate to the warmer temperatures.”

Are you ready for much warmer weather? High temperatures for inland areas should reach the 80s on Tuesday and Wednesday. Make sure to hydrate and take breaks if you have outdoor plans. #cawx pic.twitter.com/dzkjXRMzbX

— NWS Bay Area (@NWSBayArea) March 21, 2022

The next chance for rain in the region is expected Sunday and Monday, but many variables could change rainfall amounts and timing for the storm, which is still several days away from the region, Palmer said.

Offshore flow is expected to strengthen this week, with gusts up to 25 to 35 miles in the North Bay and East Bay hills. The winds are expected to have a drying effect across the region, but the recent rains have bolstered fuel moisture across the Central Coast to near-average values for this time of the year. For other regions in the Bay Area, including the Santa Cruz Mountains and the North Bay, moisture levels are still below average but are above minimum.

The weekend storm delivered about one-tenth of an inch of rain to the North Bay and San Francisco, with about 0.15 to 0.2 inches dropping in the Santa Cruz Mountains and just under 0.1 inches in the Santa Clara Valley. The Sierra Nevada received anywhere from two to four inches of snow, with the highest peaks getting up to six inches.

Wildfires have already sparked this year across the Golden State, even during what would typically be the wettest time of the year, due to the low rainfall. Fuels and vegetation have dried out as a result, requiring more storms with substantial precipitation totals to wipe out the risk.

“At this point in time, any bit of rain we get helps but, it’s not helping like we need it to help,” Palmer said. “We need a decent amount of rain to catch up,  because we were very dry during the two wettest months of the year. … We’re gonna start to dry out again but hopefully that rain we did get will help. It doesn’t mean we can’t get a fire, but the rain we got over the weekend could temper the rate of spread.”

The U.S. Drought Monitor reported Thursday that 93% of California is mired is “severe drought”, an increase from 87% from a week ago, while 35% of the state is in “extreme drought,” the most dire stage, up from 13%. Extreme drought has reached the North Coast and all nine Bay Area counties are currently in a severe drought.

Massive atmospheric river storms in October and December raised homes of ending California’s drought, which has reached its third year, but January and February were the driest on record dating back to 1921. The statewide Sierra Nevada snowpack, which provides about 30% of the state’s water needs, was at 168% of normal on New Year’s Day but had shrunk to 51% as of Monday, according to the California Department of Water Resources.

Gov. Gavin Newsom also announced Friday that the State Water Project, a massive system of pipes, canals and dams that usually provides water to 27 million people across the state, will deliver 5% of the water that was contracted to farms and cities, down from 15% in January.

“We are definitely dry,” Palmer said. “People should be conserving water.”