JACKSON, Wyo. — A ridge of high pressure building in from the south will result in dry and sunny conditions this week along with very warm temperatures. A series of disturbances will be passing north of the area, so a stray thunderstorm couldn’t be ruled out at some point, but it’s unlikely.
June 28 – July 4 Recap
We enjoyed outstanding weather conditions for most of last week, though a push of monsoonal moisture did result in an uptick in thunderstorm activity on Friday (7/1) and Saturday (7/2). Friday’s storms developed early in the day and produced frequent lightning along with gusty winds, but little in the way of rain.
On Saturday (7/2), a more substantial round of thunderstorms developed during the evening hours over the Teton Range and portions of the Jackson Hole Valley with locally heavy rainfall. This cluster of storms also resulted in a Severe Thunderstorm Warning across the Teton Range due to the potential for damaging wind gusts.
Areas under the core of Saturday’s storms received estimated rain totals of a quarter-inch to a half-inch, while other areas received next to nothing. For instance, the Town of Jackson largely missed out on these storms and only received 0.02 inches of rain on Saturday. Total rainfall for the past week in Jackson was 0.04 inches with brief/light rain recorded on three days.
Temperatures over the past week were consistently warm with highs in the 80s on six out of seven days. High temperatures ranged from 77ºF on June 29 to 84ºF on June 28 and July 3, while low temperatures ranged from 34ºF on June 30 to 45ºF on June 29 and July 3.
Forecast for Tuesday (7/5) to Monday (7/11)
Overall the upcoming week will be dry, sunny and very warm to hot in the afternoons as a ridge of high pressure builds over the Rockies. Thunderstorm chances will be minimal as monsoonal moisture remains suppressed well to the south, and a series of Pacific disturbances track to our north.
On Wednesday and Thursday, energy associated with a disturbance moving across Montana will inch toward our area, and there will be a slight chance of an afternoon thunderstorm both days as a result. However, the threat is low (but slightly higher in Yellowstone versus the Tetons) and any rainfall will be brief and light.
On Friday and Saturday, a brief afternoon thunderstorm can’t entirely be ruled out but the potential will be even lower compared to Wednesday and Thursday. Throughout the second half of the week (Wednesday to Saturday), thunderstorm chances will be much higher east of the Continental Divide across Central and Eastern Wyoming.
In addition to the dry pattern with minimal thunderstorm potential, temperatures will also gradually heat up over the course of the week with highs in the mid 80s on Wednesday and Thursday, and upper 80s on Friday and Saturday.
A weak cold front will arrive on Sunday, leading to a slight and brief cooldown. Behind the front, drier air will also arrive, resulting in near-zero thunderstorm/rain chances on Sunday and Monday.
Despite the dry pattern, winds will be gusty each afternoon through the end of the week and into the weekend.
Extended Outlook
A ridge of high pressure will strengthen over the Western U.S. early to mid next week, and this will lead to another warm-up with potentially our hottest temperatures of the summer so far.
There are also some signs that monsoonal moisture could arrive at some point during the second half of next week, which would result in an increased chance of thunderstorms following a dry start to the week.
Alan Smith, Meteorologist
Town of Jackson Climatology for July 5-11
Average High: 81
Average Low: 40
Record High: 94 (multiple dates)
Record Low: 27 (multiple dates)
Record 24-Hour Precip: 0.90″ (July 8, 1998)
