Tomorrow morning at 8am the west entrance to Yellowstone National Park (at West Yellowstone, Montana) opens to vehicle traffic for the summer season. Don't get too excited about the word "summer." That's still a long way off.

Even though you'll have to wait a little longer before the south and east gates open, this means much of the park will be accessible by car: Madison to Norris, Madison to Old Faithful, Norris to Mammoth, and Norris to Canyon Village.

The weather can be very unpredictable this time of year, so if the geysers are calling your name you'd be wise to sign up to receive text notifications about park road closures. Text 82190 to 888777 and you'll be all set. Bring warm clothes, too. Spring often has an edge to it - particularly early spring. It gets cold, especially during the overnight hours, and it might snow.

It's those cold overnights, though, that produce wonderful conditions in the early morning. If you like to photograph fog, you'll be in your element. Heated, moist air rising from thermal features runs into the supercooled atmosphere and - voilà - mist is created: sometimes thick blankets of it.

Don't expect to see fog everywhere, but if the conditions are conducive the area around Norris Geyser Basin is generally reliable as is the Grand Canyon.

The image of the Lower Falls that is posted here was made on one of those mornings; the fog was lifting out of the canyon while the sun was coming up. This was early in June and the temperature hovered just below freezing. There was still quite a bit of snow along the roadsides in the vicinity of the canyon and a few of the hiking trails there hadn't yet opened due to significant snow cover.

Springtime in Yellowstone: bundle up!

Yellowstone's (partial) opening coincides with National Park Week, which kicks off on Saturday and runs through the 28th. Entrance fees will be waived at all park properties on day one. The 20th through the 28th is a generous definition of one week; perhaps it's the park service's version of a baker's dozen. At any rate, take advantage of this window. It's a good opportunity to enjoy the parks before summer crowds descend on them.

Also coming right up, Idaho's Craters of the Moon National Monument begins its Centennial Celebration on the first of May. President Coolidge signed the proclamation on May 2, 1924 protecting this vast lava field created by dozens of fissure eruptions. In it, he described the place as "a weird and scenic landscape peculiar to itself."

I guess that makes it officially weird, but in a very good way.

Craters is 600 square miles of volcanic cinder cones, lava flows, lava tube caves, tree molds, and natural bridges. It encompasses the entire Great Rift volcanic zone and is the largest lava field of its type in the Lower 48. It's also an International Dark Sky Park. For many years it served as an astronaut field training site in preparation for trips to the moon.

The Monument is located in an area that is sparsely populated; the only lodging option is to camp. If you really want to spend some time with Craters, see it at the edges of the day, or experience those dark skies, sleeping under the stars is the way to go.

A lot of people pass by Craters of the Moon on their way to or from somewhere else, like Sun Valley or Idaho Falls. They might spend an hour or two there before moving on. I'll admit I've been one of those folks. This year, though, I plan to make it a destination - and of course the camera will be going, too.

Stay tuned.