A series of Pacific frontal systems will bring heavy rain to the Pacific Northwest, Minnesota, and the St. Louis metro area through November 4, 2026. The National Weather Service has issued flood watches for western Washington, western Oregon, and parts of the northern Rockies. Rainfall totals of 2 to 4 inches are expected in the Olympic and Cascade ranges. Urban flooding is possible in Seattle, Portland, and the Willamette Valley.
In Minnesota, a slow-moving low pressure system will produce 1 to 2 inches of rain across the southern half of the state, with embedded thunderstorms capable of higher localized amounts. The Twin Cities metro could see brief flash flooding Tuesday night. St. Louis faces a similar threat as a warm front lifts north, bringing 1.5 to 2.5 inches of rain through Wednesday morning. Minor river flooding is possible on the Meramec and lower Missouri tributaries.
Conditions improve nationwide by Thursday as high pressure builds. Monitor weather.gov for updated watches and warnings.