How stressed should Californians be about the lack of rain? Experts weigh in.

A clear and sunny day at San Francisco's Dolores Park in 2020. As of Feb. 20, the city hadn't seen any rain for the month. A clear and sunny day at San Francisco's Dolores Park in 2020. As of Feb. 20, the city hadn't seen any rain for the month. Photo: A. Graff Photo: A. Graff Image 1 of / 7 Caption Close How stressed should Californians be about the lack of rain? Experts weigh in. 1 / 7 Back to Gallery

Nearly bone-dry weather has dominated the first three weeks of February in California, and the outlook for a soaking storm before the end of the month is not promising.

Southern California has seen a few weak systems this month, with San Diego recording a quarter-inch of rain and Los Angeles a trace. But the northern half of the state has seen even less, and none of the rain gauges in the Bay Area — including San Jose, San Francisco, Oakland and Santa Rosa — have recorded any measurable rain.

The last time San Francisco saw rain was Jan. 28, when .09 was recorded, and the last downpour was Jan. 16, with 1.24 inches. Since the start of the rainy season on Oct. 1, the downtown S.F. gauge has measured 8.83 inches; normally by Feb. 19, it has recorded 17.94 inches, nearly twice as much.

ALSO: Last time SF saw no rain in February was 1864: 'We're on pace to hit that again'

The forecast through the end of the month doesn't include the possibility of any significant storms. A weak system expected to deliver sprinkles to Central and Southern California on Friday night into Saturday is highly unlikely to make it to the Bay Area.

"There has only been one other year where there has been no precipitation in February and that was 1864," said Drew Peterson, a meteorologist with the National Weather Service Bay Area. "It looks like we’re on pace to hit that again. At this point, we’re all hoping for a March miracle [a wet spring]. We’ve had them before. This is just wish-casting."

California is an arid state known for long periods without rain even in the middle of winter, but this dry spell is especially long, and some Bay Area residents may be wondering: Should I be worried? To help you answer the question we checked in with several experts.

Daniel Swain, climate scientist, UCLA, Institute of the Environment and Sustainability

Parts of California are headed for their driest February on record amidst what was already a very dry rainy season. Drought anxieties are understandably running high, given the backdrop of California's worst drought on record just a few years ago and worst fire seasons on record in 2017 and 2018.

At the moment, I would take some solace in the fact that California does have a high-degree of short-term drought resilience via its extensive system of surface water storage, which acts as a buffer against dry conditions from an urban and agricultural water perspective, at least in the short term. But on the other hand, the water stored behind dams does not help California's increasingly drought-stressed ecosystems, nor does it mitigate the potential surge in wildfire risk if we do indeed continue to head toward another drought.

So I would say the news is mixed at the moment, though the situation would become considerably more challenging if next winter is dry as well.

Scott Rowe, meteorologist, National Weather Service, Bay Area office

The San Francisco Bay Area goes through periods of midwinter dry spells nearly every year. Just two years ago in 2018, San Francisco went 27 consecutive days without any rain (Jan. 26 to Feb. 21, 2018). While many would like to see wet weather during our wet season, it's not unheard of to have a dry spell last three to four weeks.

Alison F.C. Bridger, climate scientist and professor, San Jose State University

San Jose has received a little over 5 inches of rain so far this season, and typically receives just over 14 inches for the season. Is it possible to “catch up” to normal by the end of the rain season (late-May)? It’s never happened before, so we would need “biblical” rains at this stage. On the other hand, is it possible to go the rain season with zero additional rain? That’s never happened before either. So, we are between two extreme possibilities, neither of which has happened since we began keeping records.

Most likely, it will rain some more this year, but we don’t have the skill to accurately forecast how much. One thing to consider: An increasing number of “extreme” weather events are being seen worldwide as our climate warms. Maybe one of the scenarios above could be one of them.

Jan Null, meteorologist and private consultant, Golden Gate Weather Services

This is a dry year after a wet year, and actually since the middle of 2015 or so, we’ve been alternating dry-wet, dry-wet, and if you average those years together, you get average. The stress level depends on who you are.

If you’re a farmer in the San Joaquin Valley coming out of the drought from the early-2010s, the ground water hasn’t been replenished in those areas. You’re going to be more stressed than a farmer in the Sacramento Valley, where ground water wasn’t drawn down as much. If you’re a water district manager, you’re going to be thinking, I need to start planning now in case we have another dry year next year.

Maybe we use this as a wake-up call like when the state has a minor earthquake and people stock up on provisions. Increase your awareness, but don’t increase your stress. It’s not something you can change. The amount of rain we’re going to get is the amount of rain we’re going to get.

Mike Anderson, state climatologist, California Department of Water Resources

The level of concern over this year’s dryness is area specific, and relates to timing and the potential for improvement if conditions become wetter in March and April. Water systems that have reservoir storage can buffer through a single dry year; smaller water systems that are dependent on annual precipitation are more vulnerable to dry winters; and rangeland systems are dependent on precipitation at key times.

California’s precipitation is highly variable. We can go from periods of extreme drought to extreme precipitation and back again. We know that California will experience another drought eventually, and that is why all Californians must work together to use our water wisely.

Scott McLean, public information officer, California Department of Forestry and Fire Protection (Cal Fire)

We have already seen an uptick in responses to wildfire calls. As of Monday of this week (since Jan. 1), we had received and responded to 207 wildfires compared to 81 in 2019 in the same period of time. These all being very small. The U.S. Forest Service had a wildfire at the 4,000-foot level the other day near Sierraville that burned approximately 102 acres.

The lack of precipitation along with the introduction of the north winds already this year could lead to vegetation drying out much earlier than we normally see, similar to 2017 and 2018. The mild weather has given us the opportunity to conduct more prescribed burns earlier than usual due to the favorable burning conditions. All prescribed burns are conducted under strict guidelines being cognizant of weather conditions.

With the favorable weather, residents are encouraged to start getting “ready” for wildfire as well. This is a team effort by all throughout California, for all folks in the state of California are affected by wildfires. Being ready for wildfire starts with maintaining an adequate defensible space and by hardening your home by using fire resistant building materials. Creating defensible space is essential to improve your home’s chance of surviving a wildfire.

Craig Clements, professor, Fire Weather Research Laboratory, San Jose State University

I think we should be concerned, but there is still a chance we can recover if March is really wet. And if we get some rain in late spring in addition to that, like middle of May, then that could offset the fire season somewhat like it did last year. Either way, fall will be high fire danger as it always is. But this is setting up for a drought being so far below average.

Amy Graff is a digital editor with SFGATE. Email her: agraff@sfgate.com.