Printed on: January 22, 2013

Two ice jams raise flooding concerns near Salmon river

By Laura Zuckerman
news@postregister.com

SALMON -- Weather forecasters Monday cast a wary eye on two ice jams in the Salmon River north of here that are expected to join today to renew a flood watch that went into effect on Sunday.

An extended cold snap that has brought sub-zero temperatures caused the pair of ice jams, with one roughly a mile from Salmon and the other spanning a 20-plus-mile stretch of river near North Fork to south of Carmen.

That ice jam has caused minor flooding of low-lying areas, including submerging picnic tables at Morgan Bar, a popular recreation area on a gravel bar near the Salmon River north of Salmon.

Weather observers said the deep freeze, predicted to continue at least until Wednesday, may increase the likelihood of flooding in some areas. But they said only time would tell.

"We don't know for sure. It may increase the potential for more field flooding, possibly causing water to back up a bit more," said Mike Johnson, meteorologist with the National Weather Service office in Missoula, Mont.

Salmon and surrounding towns have been islands of cold in the several days since a high-pressure ridge triggered a temperature inversion, locking frigid air into valleys even as warmer air has blanketed higher elevations, Johnson said.

Forecasters were tracking a weather system expected Wednesday that could modify the cold - or not.

"We don't know right now if it's a strong enough system to weaken the inversion that has built up in the valleys, said Johnson.

Tracking closely behind that system is yet another high-pressure ridge predicted to once again park over the area. Another bout of extreme cold could fan flooding fears.

Dale Ford, local weather spotter for the National Weather Service, said he was taking a wait-and-see stance.

"It just depends on nature," he said.