An unusual road hazard disrupted travel for several drivers in Washington state on New Year's Eve. As CBS News reports, five cars and one semi-truck were trapped by a storm of tumbleweeds that swamped a portion of State Route 240 on Tuesday night, with the stacks reaching as high as 30 feet in some spots.

Though they're normally associated with the Southwest, tumbleweeds are a common sight in some parts of Washington. Motorists driving down that particular highway often have to deal with winds tossing the shrubs into the road, but this invasion was unprecedented.

Around 6:30 p.m. on December 31, the Washington State Patrol announced that State Route 240 was closed near Richland due to the tumbleweed flood. The stretch of road buried beneath the thistles was equivalent to three football fields. According to The New York Times, local authorities had never seen tumbleweed accumulation of such proportions.

After the area was cleared with snowplows, the stranded vehicles were freed and the highway reopened at 4:30 a.m. on January 1. Such tumbleweeds storms may be unusual for Washington state, but similar events have occurred in other parts of the country. Last year, tumbleweeds in California piled high enough to trap residents in their homes.

[h/t CBS News]