National Weather Service United States Department of Commerce

Excessive Heat in the Interior West; Monsoon Conditions in the Southwest

Dangerous heat is expected to be in place across portions of California, especially the Central Valley, and across the Interior Northwest into Friday. Heat Advisories will also be in place across the southern Plains into the Lower Mississippi River Valley. Monsoonal showers and thunderstorms may result in flash flooding and debris flows from the Four Corners region and Southwest through Friday. Read More >

On the evening of March 31st, 2009, Tim Tevebaugh was driving home from work east of Craigmont in the southern Idaho Panhandle (see map below). Across the rolling hay fields, Tim saw a very unusual phenomenon. The snow rollers that he took pictures of are extremely rare because of the unique combination of snow, wind, temperature and moisture needed to create them. They form with light but sticky snow and strong (but not too strong) winds. Some snow rollers are formed by gravity (i.e. rolling down a hill), but in this case, the snow rollers were generated by the wind. These snow rollers formed during the day as they weren't present in the morning on Tim's drive to work.

Based on estimations from Tim as well as the blades of grass in the picture, most of the snow rollers were about 18" in height, while the largest rollers were about 2 feet tall.

Click on the thumbnails below for a full-size image.

 

Snow Rollers - Click for larger image  Snow Rollers - Click for larger image  Snow Rollers - Click for larger image

Snow Rollers - Click for larger image  Snow Rollers - Click for larger image  Location of Snow Rollers - click for larger view