Winter-like weather conditions contributed to two separate incidences on I-90, between Butte and Bozeman, partially blocking the westbound lanes of the interstate.

They both happened on a bridge near mile marker 252, between the Cardwell and Whitehall exits.

We talked to the tow truck operators who responded to the wrecks.  They say the first one happened when a truck and trailer jackknifed coming across the bridge.  We're told the trailer came loose and turned on its side.

The other crash happened when a state pickup truck crossed the median and hit the guardrail.

We talked to other tow truck operators who say they've been busy with other crashes.

"It was a vehicle...coming down a back road, down in Dylan, and they hit a patch of ice and they slid off the road and kind of went into somebody's front yard and clipped one of their trees," says Whitehall Truck and Towing tow truck operator Chris Whitchurch.

Whitchurch says he thinks a combination of poor conditions, unfamiliarity with the road and speed are often to blame.

"Some people think they can still drive on it like summertime, you know, can drive fast.  It doesn't take take much, just a little black ice, for you to spin out of control," says Whitchurch.

Slick, icy road conditions have folks with the Montana Highway Patrol cautioning motorists to pay close attention to changing conditions and to take extra precautions on bridges.