Hailstones at Upheaval Dome

On Saturday I hiked to Upheaval Dome, a strange geologic feature in Canyonlands National Park. It was a fun hike, very enjoyable.

Fun even though it rained, actually poured for a little while, and then hailed. The storm provided a nice break from the intense heat of the desert. I took refuge under a pine tree and watched as other hikers scrambled up and down the trail, getting soaked to the bone.

One couple from France was prepared and donned lightweight plastic ponchos, which they had in their day packs.

More thunderstorms are expected this week in Utah's southern desert. They will be most common during afternoons and can be very heavy for brief periods.

Monsoon Season in Utah's Desert
This is the beginning of Utah's "monsoon" season. From now through the end of August we can expect thunderstorms to pop up, and they can cause significant flooding. They can be dangerous if you are hiking in one of our slot canyons, where water is channeled into a small space and there is no way to get above it.

Such storms can hit anywhere, at any time. They are an anomaly in our otherwise dry desert. The typical pattern has days starting with clear skies or puffy clouds, and then thunderstorms boiling up in isolated areas during the afternoons.

I was hiking in open desert country and so rain and hail posed no real threat. Had I been in a slot canyon, the storm that hit me could have been deadly. Never enter a slot canyon without assessing the weather. Listen to the forecasts. Check at the nearest visitor center or ranger station. Then, just before you hike into the canyon, take a final look at the sky and judge whether a storm is building.

Thunderstorms can hit quickly and they usually end quickly. Mine lingered. The intense rain and hail lasted only a few minutes but then light rain continued for some time.

In many parts of southern Utah, the terrain is almost solid rock. There's no dirt to absorb water. Rain runs off the barren sandstone, channeling into ravines and flowing down canyons. A dry canyon can be inundated very quickly.

Unfortunately, people die in canyon floods. There are fatalities almost ever summer. If you take care and watch the weather, you can enjoy recreation in our canyons while minimizing risk.

Upheaval Dome
Here's the official National Park Service page on Upheaval Dome. Below is an excerpt.

"Upheaval Dome is quite a different story. In an area approximately three miles (5km) across, rock layers are dramatically deformed. In the center, the rocks are pushed up into a circular structure called a dome, or an anticline. Surrounding this dome is a downwarp in the rock layers called a syncline. What caused these folds at Upheaval Dome? Geologists do not know for sure, but there are two main theories, which are hotly debated."

Recent evidence suggests the structure is the eroded remains of a collapsed salt dome.

A more romantic theory holds that a large meteorite hit there and the dome is the eroded remains of the impact crater.

Either way, it is a great little adventure. In my opinion, it is the premier hike in the Island in the Sky District of Canyonlands. See our Canyonlands hiking page for details.

- Dave Webb