PROJECT ALERT NOTICE (MT) Minor to moderate flooding in northern Montana

Date: Tue, 17 Apr 2018 10:52:48 EDT

Summary: Minor to moderate flooding is occurring in the Milk River basin in northern Montana.

Minor to moderate flooding is occurring on the Milk River and its tributaries in northern Montana. Melting of an usually persistent low-elevation snowpack along with additional precipitation has resulted in streamflows exceeding National Weather Service flood stages at 5 USGS streamgages in the basin.

Flood crests are expected on the lower Milk River later this week and early next week. Annual exceedance probabilities have not been determined; however, streamflows are in the 99th percentile for the day-of-the-year at 6 USGS streamgages, 5 of which have more than 30 years of record.

Ice damage to one streamgage was repaired earlier in the month. No other streamgages are known to be damaged. Access to some sites has been hampered because of impassable roads.

Two crews of 2 hydrographers are deployed in the Milk River basin. An additional crew from North Dakota is measuring discharge at USGS streamgages on the Missouri and Yellowstone Rivers, freeing up Montana crews to focus on flood measurements.

Discharge measurement information, new or shift-adjusted ratings, and other information is being shared immediately with the National Weather Service via NWSChat. USGS also is participating in flood preparedness briefings by Montana Disaster and Emergency Services.