A powerful bomb cyclone, combined with an atmospheric river, is set to unleash nearly a month’s worth of rain, a feet of mountain snow, and hurricane-force gusts over parts of Northern California and the Pacific Northwest, according to various reports.
But fear not, Turlock. Stanislaus County sits near the southern tip of the system and probably will only get about an inch of rain, according to the National Weather Service in Sacramento.
“A bomb cyclone is, essentially, a low-pressure storm system that deepens or strengthens 24 millibars in a 24-hour period,” said Scott Rowe, a senior service hydrologist with the NWS. “It’s a fast-developing system. Think of it as when you’re accelerating on a freeway onramp. It’s that rate of acceleration that we’re looking at.”
While Turlock can expect about an inch of rain, the Sacramento area can anticipate anywhere from 2.5 to 4 inches of rain. Further north, Redding and Red Bluff might see 5 to 7 inches of rain.
“The farther north you go, the more rain you’ll get,” said Rowe.
For Turlock, there will be about a 10 percent chance of rain this morning, with about a 40 percent chance around midday, and a 70 percent chance in the evening.
Either way, carry your umbrella.
The National Weather Service Prediction Center issued excessive rainfall risks beginning Tuesday and lasting through Friday as the strongest atmospheric river — long plumes of moisture stretching over the Pacific — that California and the Pacific Northwest have seen this season bears down on the region. The storm system has intensified so quickly that it is considered a bomb cyclone.
More than 106,000 customers had lost power in Washington as of Tuesday evening, according to poweroutage.us. More than 11,000 had lost power in Oregon and nearly 12,000 in California.
The National Weather Service in Seattle said a peak wind speed of 68 mph (109 kph) was recorded at Crystal Mountain near Mount Rainier. A wind speed of 53 mph (82 kph) was also recorded at Ediz Hook, a 3-mile-long (4.8-kilometer) sand spit northwest of Seattle that extends from the northern shore of the Olympic Peninsula at Port Angeles into the Strait of Juan de Fuca. Winds were expected to increase in western Washington throughout the evening, the weather service said.
The areas that could see particularly severe rainfall as the large plume of moisture heads toward land will likely stretch from the south of Portland, Ore., to north of the Bay Area, according to Richard Bann, a meteorologist with the NWSPC.
“Be aware of the risk of flash flooding at lower elevations and winter storms at higher elevations. This is going to be an impactful event,” he said.
In Northern California, flood and high wind watches went into effect Tuesday, with up to 8 inches of rain predicted for parts of the Bay Area, North Coast and Sacramento Valley. A winter storm watch was issued for the northern Sierra Nevada above 3,500 feet (1,066 meters), where 15 inches (28 centimeters) of snow was possible over two days. Wind gusts could top 75 mph (120 kph) in mountain areas, forecasters said.
The system could have an impact on Friday’s high school playoff game between Turlock and Oak Ridge high schools in El Dorado Hills. Kickoff is slated for 7 p.m.
— The Associated Press contributed to this report.
