The next time you drive Interstate 84 through eastern Oregon be sure to check the speed limit because it may change from hour to hour.

New digital speed-limit signs are now fully functional between Baker City and La Grande.

The Oregon Department of Transportation says that 30-mile stretch of I-84 is a real trouble spot, in part because it is positioned between two mountain ranges.

"The goal of these projects is to reduce the number and severity of crashes in known trouble spots," said ODOT Area Manager Ken Patterson. "It will save lives and limit the amount of time the freeway is closed due to a crash or severe weather conditions."

The new digital signs use traffic, road, weather and visibility sensors to lower the legal speed limit when ice, snow, fog or an accident up ahead requires drivers to slow down.

The digital displays can also show the reason for a reduced speed. And ODOT staff can manually adjust the speed limits when necessary.