What’s next for Northern California weather? Here’s how long the rain will last

Heavy rain and high winds pummeled Northern California starting Wednesday afternoon, as an atmospheric river storm rolled through the region.

Records from the National Weather Show that the Sacramento area received rainfall totals ranging from more than half an inch of rain to nearly an inch and a half in the past 24 hours.

Sacramento International Airport recorded 1.44 inches of precipitation, while Elk Grove received the most rain in the area at 1.53 inches.

By the Bay Area, rainfall totals ranged from an inch to up to four and a half inches for that time period.

The Stockton and Modesto areas each received less than an inch of rainfall.

What’s next in the weather forecast for Northern California?

The wet weather isn’t over yet, according to the latest forecast.

Rain is expected to pour into the region on Thursday and into next week.

“The heaviest rain was expected last night, so any remaining showers will be lighter rainfall over the next couple of days,” said Sara Purdue, a meteorologist with the National Weather Service office in Sacramento.

There is a chance of thunderstorms after 1 p.m. and before 10 p.m. on Thursday and before 10 a.m. and 10 p.m. on Friday, the forecast shows.

The chance for thunderstorms across the Sacramento Valley and northern San Joaquin Valley ranges from 15 to 30%, Purdue said.

The overall chance of precipitation for the Sacramento area on Thursday is 90% during the day and 60% at night, with wind gusts of up to 10 mph, the weather service said.

During the day on Friday, the chance of rain is 60%, dropping to 40% at night with gusts of up to 10 mph.

After a few days of light rain, another storm system is expected to come through the region on Sunday and continue into early next week, Purdue said.

“We’ll see some heavier rain Sunday into Monday” in the Sacramento and San Joaquin valleys, she said.

Purdue said the next system will be fairly similar to the one that hit the region on Wednesday but with potentially less wind and more snow in the mountain areas.

She expects similar amounts of rainfall compared to the most recent storm.

How long is the flood watch in effect?

As of Thursday morning, there was still a flood watch issued for parts of Northern California, including the Sacramento Valley, Motherlode, the mountains of southwestern Shasta County, western Colusa County and northeast foothills.

It’s in effect until 4 a.m. Friday.

Purdue said there’s potential for an additional flood watch with the next storm system.

“If there’s a need for one, we’ll be issuing one closer to the event,” Purdue said.

How do meteorologists track weather systems?

Meteorologists use Doppler radar to track weather systems.

Doppler radar is among the most advanced technology used to determine the forecast. In fact, all modern weather radars are Doppler radars, according to the National Oceanic and Atmospheric Administration.

“It’s a remote sensing tool,” Purdue said, “which basically means it senses things in the atmosphere.”

The Doppler sends out a ping and if it finds something in the atmosphere, such as precipitation, within its area, it’ll notify experts.

“Depending on how strong the signal is and other factors, we can tell if the precipitation is strong or light, if it’s a thunderstorm, if it’s some other kind of atmospheric event,” she said.

The results of the radar may vary, however, depending on how you look at it.

“It’s important to interrogate the data and make sure that you’re getting the full picture based on all of the data and not just one piece of it,” she said.

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