PROJECT ALERT NOTICE (MT WY) Minor to moderate flooding continues in Wyoming and Montana

Date: Tue, 02 Jun 2020 22:27:10 EDT

Summary: Minor to moderate flooding from snowmelt runoff continues in parts of Wyoming and Montana.

Minor to moderate flooding from snowmelt runoff continues in northwestern Wyoming and south-central and northwestern Montana.

Gage-heights at ten (10) U.S. Geological Survey streamgages are exceeding or forecasted to exceed National Weather Service (NWS) flood stage. Flood warnings, watches, and advisories are in effect for reaches of the Wind River in Wyoming and on tributaries and mainstems of the Missouri, Yellowstone, Clark Fork, and Flathead Rivers in Montana. The estimated annual exceedance probability (AEP) for the June 1 peak streamflow for the Clarks Fork Yellowstone River near Belfry was between 0.02 and 0.01 and is the second largest for the period of record (99 years inclusive). Estimated AEP for other peak streamflows in the upper Yellowstone River basin were between 0.10 and 0.04.

No streamgages have been damaged or destroyed. Five crews are completing high-flow and flood discharge measurements this week for rating definition and to aid river forecasters.

Cooperators, stakeholders, and the general public are being kept informed by multiple methods including NWSChat, e-mail, and social media (Twitter: @USGS_WY and @USGS_MT).




Interactive map for flooding in the upper Yellowstone River basin, Montana