Record-breaking rainfall, flooding possible this week in East Idaho

March 21, 2018 GMT

A pickup truck plows through a flooded Interstate 86 last year in Power County.Idaho State Journal file photo

By Journal Staff

Possible record-breaking rainfall coupled with warmer temperatures will create a widespread threat of flooding this week in East Idaho.

The National Weather Service has issued an alert warning the public of the potentially dangerous conditions.

The expected warmer temps will cause snowmelt on Wednesday in East Idaho’s higher elevations, creating a flooding threat for the region that will worsen on Thursday when heavy rain is in the forecast for all of East Idaho.

Flooding is possible Wednesday and Thursday along East Idaho’s rivers and streams. Sheet flooding — rain pooling after falling on frozen ground — is also a possibility.

The National Weather Service said a half-inch or more of rain could fall on East Idaho on Thursday, with the most rain expected to fall on Thursday afternoon and evening.

If that much rain does fall on East Idaho on Thursday it will be a record-breaking precipitation event, the weather service said.

Rain is also possible on Wednesday and Friday in parts of East Idaho but not as much as on Thursday.

It’s likely that the region’s higher mountains could see snow instead of rain this week, but none of East Idaho’s towns and cities are forecast to see anything but rain, the weather service said. High winds are also in the forecast this week.

Outside of East Idaho, flooding alerts are in effect in the central Idaho mountains and in parts of south-central Idaho, as well as in Wyoming and Montana.

The weather service said motorists should definitely stay away from water-covered roads because a car can become disabled in only 6 inches of water, and if that water is flowing a car can be carried away by the force of the current.

The weather service added, “To minimize your risk of flooding, make sure you keep drains open. Also you can create runoff ditches to direct flowing water. To prevent basement flooding, remove snow from around your foundation.”

But most importantly if you encounter a flooded road, “turn around don’t drown,” the weather service said.