Atmospheric river pushes small Interior streams toward bankfull

An atmospheric river parked over Interior Alaska this weekend and dumped enough water that forecasters warned the small streams could come up to the tops of their banks.

The rain came down across the Western and Central Interior, three-quarters of an inch to an inch and a quarter in 24 hours, with another half inch to an inch and a half expected Friday night through Saturday. At those totals, the National Weather Service in Fairbanks said, two days of rain would land in the range a place sees once every five to ten years. Where it fell hardest, closer to once every 25.

The big rivers could take it. It was the feeder streams the forecasters were worried about, the ones that rise fast and give no warning.

"Anyone planning recreation activities on or along these waterways should exercise extreme caution and be on the lookout for rapidly rising water levels," the weather service said.

The warning covered a wide stretch of country: Fairbanks and the Goldstream Valley, Nenana, Two Rivers, the upper Chena and Chatanika valleys, Eielson and Salcha, the White Mountains, the Dalton Highway summits, and the Koyukuk and middle Yukon valleys.

Forecasters were describing what could happen, not what had. The outlook expired Saturday afternoon, and no flooding was confirmed on any particular stream.