Atmospheric river to bring rain, strong winds to Modesto area. How long will it last?
An atmospheric river is set to sweep through Northern California this week, bringing heavy rain and strong winds to the Modesto area, according to the California Governor’s Office of Emergency Services.
The National Weather Service predicts that the atmospheric river will arrive Tuesday and linger into the weekend, according to a news release on Monday, Nov. 18.
Courtney Carpenter, a meteorologist with the weather agency, said this atmospheric event will be “particularly different because it will kind of stall out along Northern California and bring many days of moderate to steady rainfall.”
Rainfall totals could reach up to 10 inches in some areas, and wind gusts could reach up to 70 mph.
“We’re not expecting widespread flooding at this time but ... a lot of rain is going to cause some issues across the northern portion of the state,” Carpenter said in the release.
Here’s what to expect in Modesto:
What is an atmospheric river?
According to the National Oceanic and Atmospheric Administration, an atmospheric river is an area in the atmosphere that carries water vapor outside of the tropics.
“The average atmospheric river carries an amount of water vapor roughly equivalent to the average flow of water at the mouth of the Mississippi River,” NOAA said on its website.
When an atmospheric river “makes landfall,” it often releases this water vapor in the form of rain or snow, NOAA said.
“Those that contain the largest amounts of water vapor and the strongest winds can create extreme rainfall and floods,” the federal agency said.
During the atmospheric river event, the California Governor’s Office of Emergency Services said there is a high risk of heavy precipitation that could lead to power outages, flooding and landslides.
About 30,000 Stanislaus County residents — 5.4% of the county’s total population — live in areas considered at moderate risk of flooding.
What’s in the weather forecast for Modesto?
The latest weather forecast for Modesto shows increasing cloud cover throughout Tuesday.
Temperatures will reach a high near 58 degrees and drop to a low around 48. Winds are expected to range from 6 to 10 mph, with gusts up to 18 mph.
On Wednesday, there is a 60% chance of rain, primarily after 4 p.m. The day will see a high near 61 and a low around 52, with winds of 6 to 10 mph and gusts reaching up to 20 mph.
Thursday’s forecast calls for a 30% chance of rain before 10 a.m. The high will near 69, with a low around 50. Winds will be around 10 mph, with gusts as high as 18 mph.
On Friday, there is a 50% chance of showers, with a high near 66 and a low around 54.
Thunderstorms are possible on Saturday, when the high will be near 61 and the low will be around 49.
Sunday’s forecast promises a chance of showers, with a high near 61 and a low around 47.
How much rainfall has Modesto received so far this season?
Modesto has received approximately 0.27 inches of rain this season, which began on July 1 and will continue through June 30, 2025.
How to drive safely on roads during rain
Drivers in the Modesto area should watch out for slick roads as rain returns.
Rain, coupled with speeds of 50 mph or more can result in your tires losing contact with the road, according to the Department of Motor Vehicles’ California Driver Handbook.
When it rains, drive up to 10 mph slower. “Slow down at the first sign of rain, especially after a dry spell,” the DMV website says. “A slippery road will not give your tires the grip they need.”
If your vehicle starts “riding on water” or hydroplaning, slow your car down gradually. Do not use the brakes.
