After a storm brought scattered showers and hail across the Bay Area — ending a long dry spell — residents are bracing for overnight freezing temperatures for the rest of the week.
A freeze warning, which was updated to include San Jose, is in effect from Wednesday at 2 a.m. to Friday at 9 a.m. for interior areas of the Bay Area and central coast. Vulnerable populations without shelter, elderly people and animals are particularly at risk. Vegetation that grew during the bout of warm weather could also be damaged or die during the freeze.
Temperatures only reached the mid-to-low 30s in San Jose Wednesday morning while Gilroy dipped down to around 31. Downtown San Francisco reached 42 degrees while Oakland was around 37.
“People will probably have to scrape their windows,” said NWS forecaster Matt Mehle said. “We had frost down here in Monterey.”
Hail was also reported across the region, including San Ramon and San Francisco, and a light dusting of snow grazed the peaks of the highest elevations in the Bay Area, including Mount Hamilton. The storm that moved down Monday into the Bay Area from Alaska ended a 43-day streak without any precipitation.
At 6:45 a.m., the National Weather Service’s 48-hour raw data showed around 0.12 inches of rain at Middle Peak at Mount Tamalpais, 0.22 inches at Ben Lomond, 0.07 inches at Mount Diablo, 0.04 inches at downtown San Francisco, 0.03 inches in Redwood City and Oakland and 0.01 inches at the San Jose International Airport.
“It was a really cold air mass so that led to lots of reports of small hail,” Mehle said. “It was BB size hail. Enough to cover the ground.”
Rhonda in San Ramon picked up enough hail to make a little “hail person” on her deck. @NWSBayArea @KPIXtv pic.twitter.com/0zZ2aXaOFP
— Paul Heggen (@PaulKPIX) February 23, 2022
The Sierra Nevada also received a decent amount of snow during the storm. As of Tuesday at 7 a.m., Northstar California Resort in Truckee got 13 inches of snow during a 24-hour period. The UC Berkeley Central Sierra Snow Lab, located at Donner Pass, also reported a 24-hour total of 11.1 inches of snow.
Temperatures are expected to reach the 50s Wednesday for most of the Bay Area. San Jose is projected to hit around 55 while San Francisco and Oakland are expected to hover around 56. The hills could be chillier, into the 40s. For Thursday, most of the region is expected to be in the upper 50s and right around 60. Overnight lows are projected to be in the widespread 30s, with interior places dropping down to the mid-to-upper 20s. San Jose has an overnight low of 31.
By Saturday night into Sunday morning, temperatures are expected to warm up again, with overnight lows back in the 40s for most of the region. Afternoon highs are expected to be in the mid-to-low 60s.
High pressure ridges led to a recent dry spell, pushing any prospective storms into the Pacific Northwest instead of allowing them to drop into the Bay Area. The weather pattern is typical of a La Niña occurrence in the Pacific Ocean, in which cold water rises and leads to droughts in western parts of the country. A few days ago, the high pressure moved west, enabling the storm to move in from Alaska.
The rain and snow were welcomed in a drought-stricken California, whose state water supply has been impacted during the stretch of dry weather. Atmospheric river storms in October and December replenished the statewide Sierra Nevada snowpack to 168% of normal on New Year’s Day and marked the 21st wettest December on record for San Francisco, which has climate records dating back to 1849. By Tuesday, the Sierra snowpack had dipped down to 67% of normal, according to the California Department of Water Resources.
CA snowpack down to 67% of avg for the date as of today’s update. Today’s modest snowfall (~0.5 inch of SWE) may add a percentage point or two, but % of avg will start dropping again soon. But more uncertainty heading into Mar–things looking a bit more active? Stay tuned. #CAwx pic.twitter.com/fe03dKUrHx
— Daniel Swain (@Weather_West) February 22, 2022
There’s another chance for rain at the end of the month, starting as early as Saturday night into Sunday for the North Bay and the rest of the Bay Area Sunday and Monday. However, it’s not shaping up to be a big system.
“The rainfall we got is not going to impact the drought,” Mehle said. “Our rain chances begin to taper off when we hit March. There are some years where we get a ‘Miracle March,’ but right now, the long-term models are not suggesting a lot of rainfall for March.”
Source: www.mercurynews.com