A change in the weather pattern is expected to bring heavy rain and gusty winds from Washington to California this week. A low pressure system will set up over the Gulf of Alaska by mid-week and will start sending moisture into the west coast by late Wednesday night. This low will tap into a plume of tropical moisture to bring heavy precipitation from the coast to the Cascade Mountains. This set up is described as an “atmospheric river” because the plume of moisture carries a significant amount of water vapor and can result in heavy rain for several days.
First #atmosphericriver event of the season on the way with a lot of available moisture. #Rain returns starting late Thursday. #cawx pic.twitter.com/n4QdB2fy4k
— NWSBayArea (@NWSBayArea) October 10, 2016
Pay attention to fcst this week! Thu thru next Sunday very stormy. Flooding rain possible, and a few damaging wind opportunities. #wawx pic.twitter.com/0iaSsuZru7
— NWS Seattle (@NWSSeattle) October 9, 2016
Two rounds of heavy rain and strong winds are expected. The first will be on Thursday and then again on Saturday. There is a threat for flooding as some areas of Washington, Oregon and California could see 5-10 inches of rainfall.
Rain is expected to make it as far south as the Bay Area in California, but rain totals there will likely be less than an inch. Temperatures will also stay mainly below average through the weekend for much of the Northwest and northern California.
For WeatherNation, Meteorologist Corey Christiansen