JACKSON, Wyo. – Temperatures in July have been close to average, while rainfall amounts have been highly variable across Teton County. August is projected to be warmer and drier than average as fire danger continues to rise.
Recent Weather and Preliminary July Recap
The past week has been very dry across Jackson Hole with large temperature swings between day and night.
On several mornings, low temperatures briefly dipped into the 30s in the town of Jackson before warming up well into the 80s during the afternoon.
The most dramatic temperature swing was on Monday, when a morning low of 36ºF was followed by an afternoon high of 90ºF, which was then followed by an overnight low of 37ºF.
There are not many places in the world where you can have a low temperature in the 30s and a high temperature of 90ºF on the same day!
These big temperature swings are also indicative of the dry airmass that has been in place.
For the month of July as a whole, temperatures are going to end up right around average in the town of Jackson. While we still have one more day left in the month, the preliminary average high and average low for July 2025 are 84.1ºF and 43.2ºF.
The warmest temperature of the month was 91ºF on July 13, and the coldest temperature of the month was 36ºF, which occurred on three separate mornings. Overall, there were three days with 90+ degree high temperatures in Jackson during July.
Despite the dry spell recently, rainfall in the town of Jackson has actually been above-average this month. This was the result of two active stretches at the beginning of the month and in the middle of the month.
Overall, Jackson has recorded 1.21 inches of rain in July through the morning of the 30th, which is above the July average of 0.79 inches. July is the only month of the year with a precipitation average of less than an inch in Jackson.
Teton Village and Wilson also received some heavy downpours earlier this month, and the mid-mountain plot at Jackson Hole Mountain Resort has received 2.50 inches of rain this month.
Unfortunately, other parts of Teton County, Wyo., and Teton County, Idaho received much lighter rainfall totals in July, with some locations picking up less than a half-inch total for the month.
On the heels of a very dry June throughout the region, fire danger may continue to rise heading into August unless we can pick up some substantial late summer rains.
Here are the monthly weather stats for the town of Jackson since October 1:
Here is the precipitation summary for Jackson since October 1.
Believe it or not, precipitation just in town is close to average for the water year, though other locations across Teton County and Western Wyoming are below average. In other words, the town of Jackson’s precipitation this year is not representative of the region as a whole.
Current and Upcoming Weather Pattern
The pattern is turning more active for the next several days as a series of Pacific disturbances track across the Northern Rockies.
Scattered thunderstorms developed over the area on Wednesday afternoon, including a couple of intense cells directly over the Teton Range. The webcam at Dornan’s (courtesy of seejh.com) captured a lightning bolt striking the Grand Teton at 5:16 p.m. on Wednesday.
Daily afternoon thunderstorm chances will continue from Thursday to Saturday, so plan your outdoor activities accordingly… especially if you plan on bagging a peak or being out on the water.
We will be just on the southern fringe of these Pacific disturbances later this week, and moisture levels will not be very impressive as a result. While some downpours could certainly occur underneath stronger thunderstorms, most areas are expected to see only light rainfall in this pattern.
East of Jackson Hole, deeper moisture will be in place with more numerous thunderstorms and heavier rainfall expected across Central and Eastern Wyoming. Yellowstone will also be more favored for thunderstorm coverage and rainfall versus the Tetons.
The thunderstorms in this pattern are not monsoonal in nature, as is typically the case at this time of year. The North American Monsoon has weakened significantly lately, and areas that typically see more moisture, such as Arizona and Utah, have been bone dry and have been experiencing large wildfires.
Next week, another low pressure system is expected to pass just a bit too far north of our area, and our forecast is trending drier as a result.
Here is the 7-day precipitation projection from the European Ensemble Model:
August Outlook
Average rainfall in Jackson Hole increases in August after bottoming out for the year in July, as monsoon moisture intrusions are more common. From 2010 to 2024, average rainfall in July in Jackson was only 0.79 inches, while average rainfall in August was 1.52 inches.
August is also the second warmest month of the year, just slightly cooler than July. However, nights tend to become noticeably cooler as the month progresses due to decreasing daylight hours.
During recent years, we have seen abundant rainfall in August. From 2021 to 2023, August rainfall was well above average, including an impressive 3.65 inches in August 2022. Rainfall was just slightly above average in August 2024, but continued the streak of four consecutive above-average Augusts.
While anything is possible, medium to long-range projections are hinting that our wet August streak could end this year, as warmer and drier than average conditions are favored.
The monsoon is turning out to be very weak this year, with limited and inconsistent moisture remaining confined to the Southwest during the first couple of weeks of the month.
To the north, weak disturbances are expected to pass just a bit too far north of our area early in the month (favoring Montana more so) with only light rain projected locally.
It’s possible we may not see any more monsoon moisture surges this year if the monsoon remains weak and suppressed to the south. If we do see any more surges, it may not happen until mid to late August.
As a result, drier-than-normal conditions are more likely in August this year unless we can see some moisture-laden Pacific storm systems move through (which, while not unheard of, are not typical in August).
Temperatures are expected to start out near average through the first 7-10 days of August, but then longer-range signals are hinting at a trend to above-normal temperatures by mid-month.
Most long-range projections favor above-normal temperatures for the month as a whole.
Here are NOAA’s August temperature and precipitation outlooks that were issued on July 17. The next outlooks will be issued tomorrow, but I suspect the warm and dry signals will remain in these outlooks for our area.
Fire danger has continued to rise across Western Wyoming, so the warm and dry outlook for August is not ideal in this regard. Let’s hope that we can see more moisture than what is currently projected!
Alan Smith, Meteorologist
