Star Valley and much of Western Wyoming had a rather dry and warm July. While there are currently many fires burning to the west of Wyoming, particularly across Northern Nevada and California, due to the rather wet spring the only noticeable effect in Star Valley has been increasing smoke. However, the longer range forecast for much of western Wyoming and Southeast Idaho is a continuation of the warm and dry weather of July through much of August. Forest and grasslands are now becoming quite dry in the Star Valley region, and with little signs of significant moisture the threat of fires will continue to increase.
A graph of this July daily maximum and minimum temperatures from Thayne Elementary School weather station show little change from day to day.
There were a few good showers that fell in Star Valley in July, but totals amounts were generally under half an inch. Star Valley Ranch was one of the driest with just .18 for the entire month. Normal July rainfall is about an inch and a half.
The outlook for August by the National Climatic Center is more of what July offered, warm and dry across much of the intermountain area including Star Valley.
The monsoon moisture which has been evident much of July across the Southwestern States could make its way north into Western Wyoming during the month providing potential wetting showers for the forests. However, the current weather pattern with an upper high to our south would have to shift east allowing for the moisture to move north.
The normal rainfall for Star Valley in August is about the same as July, around an inch and a half. Year to year August precipitation can very dramatically. Recent years have seen ranges from .14 in August 2017 to nearly 6 inches in August of 2014. The key to a wet August is for the monsoon moisture to make it northward into Wyoming. That is very difficult to forecast much more than a week or so ahead. Thus monsoon and thunderstorms could be a big player in August if the pattern becomes more favorable for precipitation than the current forecast is calling for.