Winter Storm — Southwest Big Horn Basin, Wyoming

2013-10-03 to 2013-10-04 · Southwest Big Horn Basin, Wyoming

Event narrative

A trained spotter reported 7 inches of snow in Thermopolis.

Wider weather episode

A potent early season winter storm moved into Wyoming early on Thursday, October 3, and continued through much of Friday, October 4. Snow began in the higher elevations of western Wyoming early Thursday morning. Rain across the lower elevations changed to snow during the afternoon and evening hours of Thursday as colder air moved across Wyoming from west to east. With impressive upper level dynamics and ample moisture, snowfall rates approached two inches an hour at some locations.

The wet, heavy snow fell on trees that still had full foliage and brought many limbs and trees down onto streets and power lines. Natrona County was hardest hit with 14,000 customers without power at the peak of the storm. Several warming shelters were established Friday along the I-25 corridor to help those without heat. The heavy snow also brought many road closures to central Wyoming. In Casper, snowfall of 16.2 inches was the tenth highest storm total since records began in 1937 and held a liquid water content of 2.14 inches. The highest snowfall amounts fell in the higher elevations with over two feet of snow recorded in the higher elevations of the Wind River, Bighorn, and Absaroka ranges, as well as Casper Mountain. The highest amount was at the Reno Hill SNOTEL where 34 inches of snow was recorded. Many lower elevation locations east of the Continental Divide reported 6 to 12 inches of snow.

Source: NOAA Storm Events Database, event_id 476142. Narrative written by the NWS forecast office that issued the report.