Heat waves baking the East Coast, torrential rains dousing the Midwest. In Yellowstone National Park, it's snow that's highlighting the park's weather.

Indeed, with the official start of summer less than two weeks off, road crews in Yellowstone are battling late-season snowstorms that have forced closure of some park roads.

While officials say "a normal winter has been followed by a normal spring," the problem is that "it’s been almost a decade since Yellowstone has had a normal winter and spring."

According to rangers, Yellowstone's campgrounds and trails are opening later this year than in the recent past. A series of late spring storms has brought repeated and continued snowfall to areas of the park, prompting some temporary road closures in recent days.

This past weekend, for instance, snow caused temporary road closures through Hayden Valley, Sylvan Pass, Craig Pass, and the park’s East and South Entrances. Dunraven Pass between Canyon Junction and Tower Falls has been particularly troublesome for the park’s road crews. Heavy snow prompted a closure of the road last Thursday. Crews were unable to reopen that stretch of the park’s Grand Loop Road until late Monday morning.

To the east of the park, the Montana Department of Transportation is still working to deal with problems on a section of the Beartooth Highway. The segment of US 212 from south of Red Lodge to the Wyoming State Line remains temporarily closed to travel.

Visitors can still travel from Red Lodge to Cooke City, Silver Gate, and the park’s Northeast Entrance by taking Montana Highways 308 and 72, Wyoming Highways 120 and 296, and the open section of US 212.

While all park entrances and all roads inside Yellowstone National Park are currently open to travel, the National Weather Service forecast calls for daytime temperatures in the 40s and overnight lows below freezing, with a chance of snow through Thursday night.

The bottom line? Yellowstone's weather is very unpredictable. Visitors should be prepared for a wide range of spring weather conditions, possibly including another round of temporary road closures. Park visitors are encouraged to bring warm clothing and have flexible travel plans.

Updated Yellowstone National Park road information is available at all visitor centers. Current road information is available 24 hours a day by calling 307-344-2117. The Montana Department of Transportation Traveler Information hotline number is 800-226-7623.