August Climate Summary for Central and Western Wyoming

The August 2025 climate summaries for Big Piney, Buffalo, Casper, Greybull, Lake Yellowstone, Lander, Riverton, Rock Springs, and Worland are now available online.

Big Piney

Buffalo

Casper

The month of August was warmer than normal and mainly drier. The weather saw a fluctuation between hot, dry and windy days, to cooler days with showers. The first few days of August were warm with scattered thunderstorms and rain showers. The main issue was gusty winds and virga. Not a lot of precipitation reached the ground. The first full week had hot and dry conditions in most places with Red Flag Warnings across the southern half of the state. The weekend of 9th -10th had cooler temperatures with a few isolated thunderstorms, mainly Natrona and Johnson counties. There were also a few new record low temperatures set. The next week saw increasing temps once again, and increased fire weather conditions by mid week.

Thursday - Sunday, 14th -17th saw widespread thunderstorms. The primary impact was strong outflow winds upward of 40 to 50 mph. Worland had the highest gust speed of 71 mph from the southwest, with Riverton airport seeing a gust of 68 mph. Rock Springs and Greybull had peak gusts during the month of 63 mph. These gusty winds helped feed the fires located across the state. A new fire start in Bighorn Basin was the biggest impact and spread rapidly and caused widespread evacuations in the region east of Thermopolis.

The week starting on the 18th was back to drier conditions with hot temperatures, but the threat of convection was much lessened. Mid week brought near record highs to the region. Several locations hit the 99 degree mark, with record highs on the 19th and 20th. Greybull and Worland both hit 101 degrees. There was a new fire start in the Dollar Lake region of Sublette county. The end of the week cooled off again with some convective activity. The final week of the month was dominated by the monsoon with isolated to scattered thunderstorms. This brought a little more needed moisture to the area. Temperatures were below to near normal. The last day was a little warmer with patchy smoke from numerous wildfires.

Check the CLMs for more specifics on daily records set at the various locations. See the links above for details for individual sites or click here for Water Year Precipitation summaries for more locations.

If you would like additional, or more in-depth climate information, please refer to our Climate Page. From the Riverton Home Page, hover over the "Climate and Past Weather" tab, and select the "Local" option. Under the "Observed Weather" tab you can then find the Daily Climate Report (CLI), the Preliminary Monthly Climate Data (CF6), and the Monthly Weather Summary (CLM). The Daily Climate Report will have the weather data for the day (from midnight to 1159 pm). The Monthly Climate Data (CF6) will have this data for each day of the month, compiling all the daily data into one form. There is also a link to the Record Event Reports (RER) and the Annual Climate Report (CLA).