Long Tom River at Monroe, OR
River level and flood forecast · Benton County
The river is 4.2 ft below flood stage (9 ft).
Forecast to hold near 4.8 ft through Mon, Oct 19, 5 PM.
Flow: 301 cubic feet per second (USGS).
The last 7 days and the forecast
NWS forecast issued Mon, Oct 12, 8:25 AM. Forecasts change as rain falls and as upstream water arrives.
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An email when the National Weather Service forecasts Long Tom River at Monroe to flood, when it floods, and when it's over.
Flood stages
| Major flood stage | 12 ft |
| Moderate flood stage | 11 ft |
| Flood stage | 9 ft |
| Action stage | 8.5 ft |
| Record crest (January 15, 1974) | 10.42 ft |
What floods at each level
From the National Weather Service, highest first.
- 12 ftflooding impacts buildings in parts of Monroe, especially between Territorial Road and the river. Also expect flooding of the City Park, numerous farms in the area, and several rural roads.
- 11 ftflooding threatens some buildings in Monroe between Territorial Road and the river, along with the City Park just north of Hwy 99 and numerous rural roads and farms.
- 10 ftflooding impacts some roads and agricultural land in the vicinity of Monroe, and may threaten some homes in low-lying areas.
- 9 ftflood waters threaten some roads and low-lying agricultural land in the vicinity of Monroe.
Highest crests on record
- 10.42 ft — January 15, 1974
- 10.08 ft — February 7, 1996
- 10.06 ft — December 26, 1964
- 9.59 ft — January 21, 1972
- 9.54 ft — January 18, 2006
Recent crests: 9.11 ft (April 9, 2019) · 8.93 ft (January 19, 2012) · 9.54 ft (January 18, 2006) · 9.33 ft (December 28, 1998) · 9.04 ft (November 19, 1996)
Up and down the river, and nearby
Not an official source. River levels, forecasts, flood stages and impacts are from the National Weather Service (MNRO3); flow from the U.S. Geological Survey. Readings are provisional. In a flood, follow your local officials and the NWS at weather.gov.