High winds are taking a toll on Boulder County after two semitrucks rolled over on Colorado 93, closing the highway for much of Thursday, Colorado 128 was closed and sidewalks at the University of Colorado Boulder were blocked for trees at risk of falling on pedestrians.

Colorado 93 reopened after two semitrucks crashed and rolled over on the highway, amid a windstorm and low visibility. Some University of Colorado Boulder sidewalks are closed because a tree has a large crack and is at risk of falling.

One fallen semitruck caused the Colorado 93 closure, according to a Boulder County Sheriff’s Office post on X. The highway was closed between Colorado 128 and Colorado 72 for more than seven hours, according to COtrip, the Colorado Department of Transportation’s traffic mapping website.

Colorado 93 reopened as of 3:10 p.m. after having closed around 8:45 a.m., according to COtrip.

The driver of that semitruck, a 38-year-old man, was taken to the hospital, according to the release. The agency did not know how serious the man’s injuries were.

A Subaru Outback was also involved in the crash, the release said. Colorado State Patrol did not specify how the car was involved or if anyone in the Subaru was injured.

Colorado State Patrol troopers responded to that rollover around 8:44 a.m., according to a Colorado State Patrol release.

Another semitruck rolled over about 45 minutes later, around Colorado 93 and the Rocky Flats Wildlife Refuge at West Gate Road, according to the release. No one was reported injured, but the truck was reported to be leaking fluid, according to the state patrol’s release.

Video posted to X by the Jefferson County Sheriff’s Office shows the truck blocking part of the road.

Video of the semi rollover along Highway 93.#cowx pic.twitter.com/d55Avtr5HO

— Jeffco Sheriff (@jeffcosheriffco) March 12, 2026

Colorado 128, which was closed between Colorado 93 and Eldorado Boulevard in Superior for safety concerns, had reopened as of 1:45 p.m., according to COtrip.

In Boulder, a tree is cracked and at risk of falling in the high winds on CU Boulder’s campus near the Guggenheim Building, prompting university officials to close sidewalks northwest of the building, according to a CU Boulder alert. People are asked to avoid the area while university officials monitor the tree, the alert states.

Colorado 93 often closes during high wind events, like in December, when the road, along with Colorado 128, was closed in the same area amid wind gusts over 100 mph. Winds gusts were forecast to reach as strong as 75 mph in Boulder on Thursday, with sustained winds as fast as 40 mph, according to the National Weather Service.

Officials warned of high fire danger on Thursday because of the wind and low humidity. Wind gusts are expected to reach as high as 67 mph in the area of the closure, according to COtrip, which also warns of dry conditions and low visibility.

The National Center for Atmospheric Research Mesa Lab in Boulder already recorded max gusts over 65 mph as of about 9:45 a.m.

This is a developing story and may be updated.