The slim chance that some regions of the Bay Area would see rain this week from a low-pressure system has reverted to virtually no chance, according to the National Weather Service. At the same time, the agency said the more likely chance that dangerous fire conditions may develop has morphed into a certainty.
Neither scenario is going to reflect real significantly on the temperature gauge.
“The rain we thought we were going to get was more in the North Bay, in Napa and Sonoma counties,” NWS meteorologist Alexis Clouser said Tuesday. “But right now, we aren’t even expecting to get traces of rain anywhere. The system just was not strong enough. That being said, that low pressure that was supposed to bring us rain is going to keep us with cooler temperatures.”
Yet, while cooler temperatures may keep that aspect of the weather comfortable, part of the system is creating a lack of comfort elsewhere. Clouser said the system is tracking over the state instead of moving over the ocean, a scenario that is expected to create strong off-shore winds that blow toward the ocean.
In hotter conditions, those might create red-flag conditions for fire danger. This time, the weather service issued a fire weather watch that will start Thursday and run through Saturday evening. According to the weather service, higher elevations in the region could see wind gusts of up to 40 mph, with isolated gusts of 50 mph.
“It’s not the temperatures we’re worried about so much as it is the off-shore winds,” Clouser said. “That will dry out the grass fuels even more, and the humidity will be critically low. It’s going to be very windy and very dry.”
Safety officials urged residents to be cautious with the fire conditions, urging them to cut back on defensible space in front of their homes and to avoid doing activities that may create a spark or heat up dry vegetation, such as mowing the lawn.
Temperatures that on Tuesday are expected to peak in the low 80s and high 70s in the hottest spots while topping out at about 70 near the water likely will drop a few degrees Wednesday and Thursday before jumping up again Friday. Areas near the coast may be 10 degrees warmer on Friday but the hottest interior spots are expected to stay in the low-to-mid 80s
“Once the winds die, it’s going to pretty mellow,” Clouser said.