JACKSON, Wyo. – Following a cooler and wetter than average three-month period from April to June, we saw a transition to a hot and dry weather pattern in July. In fact, this July was the driest in Teton County since 1988. August is looking more promising in terms of rainfall potential, however.
July 2022 Review
July was hotter than average and much drier than average across Teton County and Western Wyoming. A ridge of high pressure was the dominant pattern across the Western U.S., resulting in above-average warmth throughout the West.
Moisture associated with the North American Monsoon across the Southwest U.S. only reached Western Wyoming on a few brief occasions and thunderstorm activity was spotty over the course of the month with little rainfall.
July 2022 was in the top 10% of hottest Julys across Teton County and Western Wyoming, while it was also one of the driest Julys on record.
Drought conditions worsened across Teton County over the past month, and the southern part of the county is back into an “Extreme Drought” according to the U.S. Drought Monitor. Most of Yellowstone National Park is still drought-free in response to a very wet June.
July is the driest month of the year on average in Teton County and Northwest Wyoming, but even so, this July was exceptionally dry. The Town of Jackson only received 0.06 inches of rain during the month of July, which is well below the average of 1.12 inches.
Marginal amounts of rainfall were recorded in Jackson on four days in July. Thunderstorm coverage and rainfall were a bit better north of Jackson as Moran recorded 0.36 inches of rain in July and Moose recorded 0.41 inches.
However, even north of town, these rainfall totals were still well below average. For Teton County as a whole, this was the driest July since 1988, which was the same year as the devastating Yellowstone fires. Fortunately, we are not in such a dire fire situation this summer thanks to more abundant precipitation received in prior months.
Temperatures in Jackson were 2.2ºF warmer than the long-term average for July, but not quite as hot as July 2021. For July 2022, the average high temperature in Jackson was 85.8ºF and the average low was 42.3ºF.
High temperatures in Jackson topped 80ºF on all 31 days in July, with highs ranging from 80ºF on July 1 to 93ºF on July 18. Low temperatures ranged from 35ºF on July 5 to 55ºF on July 18 and July 23.
Although there were numerous days with highs in the upper 80s, the high only topped 90ºF once in July 2022, compared to July 2021 when there were seven days with highs of 90ºF or higher.
A more noticeable improvement over last July was the relative lack of smoke this July. Although we had a few hazy days toward the end of the month, smoke conditions were significantly worse last July and stuck around for most of the summer.
Monthly Temperatures for Jackson (Water Year to Date Since October):
| Month | Avg High | Avg Low | Departure | Highest | Lowest |
| October | 56.5 | 29.0 | + 1.7 | 73 | 18 |
| November | 46.3 | 24.0 | + 7.4 | 59 | 6 |
| December | 35.3 | 21.0 | + 10.2 | 58 | -6 |
| January | 22.7 | -3.3 | – 7.0 | 42 | -19 |
| February | 29.9 | 3.0 | – 4.8 | 46 | -16 |
| March | 45.3 | 18.3 | + 0.8 | 66 | -15 |
| April | 46.0 | 24.1 | – 4.6 | 64 | 1 |
| May | 57.2 | 33.0 | – 2.6 | 79 | 18 |
| June | 71.2 | 38.6 | – 0.5 | 86 | 29 |
| July | 85.8 | 42.3 | + 2.2 | 93 | 35 |
| Water YTD | + 0.3 |
Monthly Precipitation for Jackson (Water Year to Date Since October):
| Month | Precipitation | Departure | Days of Precip | Snowfall | Departure |
| October | 1.71″ | + 0.30″ | 10 | 0.5″ | – 1.5″ |
| November | 1.35″ | – 0.36″ | 6 | 0.7″ | – 10.8″ |
| December | 1.83″ | + 0.19″ | 18 | 26.6″ | + 8.5″ |
| January | 1.23″ | – 0.05″ | 8 | 15.1″ | – 3.9″ |
| February | 0.29″ | – 0.89″ | 4 | 5.1″ | – 8.5″ |
| March | 0.66″ | – 0.60″ | 8 | 10.0″ | + 2.3″ |
| April | 1.95″ | + 0.65″ | 13 | 17.2″ | + 14.5″ |
| May | 2.19″ | – 0.01″ | 16 | 1.1″ | + 0.5″ |
| June | 1.58″ | + 0.08″ | 10 | 0.0″ | – |
| July | 0.06″ | – 1.06″ | 4 | 0.0″ | – |
| Water YTD | 12.85″ | – 1.75″ | 97 | 76.3″ | + 1.1″ |
August 2022 Outlook
For as dry as July was across Teton County, August is looking much more favorable in terms of rainfall potential.
On August 2, we already saw our wettest day since June as widespread strong thunderstorms associated with a significant surge of monsoonal moisture moved across Teton County. Western portions of the Tetons received up to an inch of rain, while Jackson received 0.25 inches and Teton Village 0.38 inches.
Unfortunately, the August 2 thunderstorms also resulted in a terrible incident as two backpackers who were part of a NOLS group in the Teton Wilderness were struck by lightning. Sadly, one of the two backpackers who were struck did not survive, and the other was hospitalized with major injuries.
Another significant surge of monsoonal moisture is expected to arrive on Friday and Saturday with widespread rainfall, locally heavy rainfall, and active cloud-to-ground lightning expected on both days.
Another uptick in monsoonal moisture is possible next week as well. Overall, the pattern looks to favor frequent moisture intrusions into Western Wyoming. As a result, Teton County looks to be favored for a wetter-than-average August.
Thunderstorm activity should also be a bit higher than usual this August, which means an increased lightning risk for those spending time in the backcountry.
Despite the uptick in moisture, August 2022 is expected to be warmer than average for the second month in a row, though probably not as hot as July.
Historically, August is the second warmest month of the year in Jackson with an average high of 81.1ºF, an average low of 39.6ºF and average rainfall of 1.23 inches. Nights typically start to become noticeably more chilly toward the end of August as the days become shorter.
As far as fire danger goes, the National Interagency Fire Center has Teton County right on the edge of having “Normal” to “Above Normal” potential for significant wildfires in August and September.
Rainfall from thunderstorms is always tricky as it can be hit or miss in nature. Fire danger in Northwest Wyoming is rated as “High” by Bridger-Teton National Forest and the Teton Interagency Fire Center (which is typical for this time of year), but if we can get some widespread rainfall from the upcoming monsoon surges, then this could potentially temper our fire danger a bit.
That being said, August is also the peak month for fires and smoke across the Western U.S., and we will probably see some occasional smoke work its way into the area – but probably not as bad as last year.
Alan Smith, Meteorologist
