Across Northern California, temperatures are predicted to spike on Tuesday, which is the first day of summer, according to the National Weather Service.
UCLA climate scientist Daniel Swain tweeted that a “major weather pattern change” is on its way to California this week, following a pleasant weekend. While temperatures in the north have been relatively chilly recently, “a sustained spell of much hotter temperatures is forecast inland,” according to the National Weather Service.
This week, the weather in the state is about to take another turn, according to Swain “An early/pre-monsoon surge is expected to hit the southern two-thirds of California by mid-week. Even if you don’t see lightning in the lower elevations, this could produce at least mountain/desert t-storms. There may be some dry-ish lightning in the drought-stricken area.”
It is expected that triple-digit temperatures will continue into the weekend in several parts of the state’s Central Valley. The hottest days of the week are expected to fall on Tuesday and Wednesday in the Central Valley. Redding, California, is expected to reach 104 degrees on Tuesday and 107 degrees on Wednesday. According to the National Weather Service, temperatures will soar to 102 degrees in Sacramento on Tuesday and Wednesday.
Weather service forecaster Scott Rowe tells NBC Sacramento, “We’re not anticipating any records, but we’re going to be around 10 to 15 degrees over usual for this time of year.”
Discovery Bay is anticipated to reach 105 degrees, Concord 103, Santa Rosa 100, San Jose 98, Oakland 93, and San Francisco 83 degrees this week’s high in the San Francisco Bay Area.
Sarah McCorkle, a forecaster for the Bay Area office, said, “It’s going to be hot through Wednesday, Thursday, and then start to cool down a little bit on Friday.”
Monday analysts said it was too early to predict exactly what this low-pressure system will bring to Northern California, but the monsoon surge is expected to arrive on Wednesday. Although dry lightning and thunderstorms are highly improbable in the Bay Area, forecasters expect a modest dip in temperatures as a result of the weather shift.
Forecasters predict that temperatures will remain in the 90s and lower on Wednesday, but will be a tad cooler than on Tuesday.
According to Rowe, the Sierra crest is the area most likely to have thunderstorms and dry lightning.
It’s hard to predict where this rain will go, he said. “Dry lighting along the Sierra crest is now predicted to occur with a 10% to 20% possibility. You can’t tell what’s going to happen.”
In the summer, dry lightning can start wildfires, but Rowe says the Sierra Nevada’s fire risk is only moderate because of recent light rain, which has kept the vegetation moist enough to prevent this from happening.
Southern California’s deserts have a higher likelihood of monsoonal moisture-induced thunderstorms, including both dry lightning and light rain.