JACKSON, Wyo. — The past week was rather quiet in terms of precipitation across the Jackson Hole region. Cooler than average temperatures early in the week gave way to warmer than average temperatures late in the week, before cooling off again on Sunday. Temperatures over the past seven days ranged from a low of 29 on the 9th to a high of 82 on the 12th.
While snowfall was above average this past winter, unfortunately, we have experienced below-average precipitation over the past two months, which is a worrisome trend heading into fire season (July-September). The map below shows precipitation anomalies over the past 60 days.
Temperatures have generally been close to average over the past two months across Northwest Wyoming, which is fortunate as this has prevented us soil and vegetation from drying out too quickly thus far, as we are still very much in the “green-up” stage.
Soil moisture is currently right around average across Western Wyoming, but this is a change from a month ago when soil moisture was above average.
Snowpack has continued to rapidly decline across the higher elevations. Snow depths on June 15 range from 46 inches at Jackson Hole’s Rendezvous Bowl Plot (elevation 9,580 feet) to 35 inches at Grand Targhee (elevation 9,260 feet). These values are near average for June.
Weekly Weather Outlook — June 15-21
We’ll see a nice start to the week on Monday, but then a late season low pressure system will drop in from the northwest, bringing two days of cold and wet conditions on Tuesday and Wednesday, including mountain snow. Conditions will dry out on Thursday and Friday with temperatures remaining cooler than average, before a more noticeable warm-up occurs over the weekend.
Monday:
This will be the nicest day of the week as we’ll be in a break between systems with highs rising into the low 70s. Mostly sunny skies early will give way to increasing clouds in the afternoon along with breezy southwest winds.
Tuesday:
The approaching trough of low pressure packed with Pacific moisture will arrive early Tuesday morning (before dawn) along with an associated cold front, leading to widespread rain showers throughout the day. High temperatures could occur during the morning hours before remaining steady or slightly falling into the afternoon.
Snow levels will generally range from 9,000-10,000 feet during the day before gradually falling on Tuesday night.
Wednesday:
We may see some lulls in the action late Tuesday night/early Wednesday morning, before a second cold front arrives early Wednesday morning with snow levels falling to 7,000-7,500 ft. Showers will continue off-and-on throughout the day, though perhaps more intermittent compared to Tuesday, at least in the valley.
Snow levels will rise to 7,500-8,500 ft. during the afternoon with continued accumulations across the higher elevations.
Total rainfall and precipitation amounts from Tuesday through Wednesday will range from 0.5-1.25 inches across the higher elevations of the Tetons and for much of Yellowstone National Park. Total snow amounts above 9,000 feet will range from 3-6 inches with even higher amounts expected above 10,000 feet.
Thursday-Friday:
Conditions will dry out late this week as the system exits the region. There is at least a small chance that some afternoon showers/thunderstorms could develop on Thursday and/or Friday afternoon, but weather models are in poor agreement at the moment so it’s possible that conditions could be rain-free as well. Temperatures will be warmer on both days, but will remain cooler than average for mid-June.
Saturday-Sunday:
The good news is that after a cool and unsettled week, the weekend is looking fantastic with temperatures warming up well into the 70s to near 80 under mostly sunny skies with generally dry conditions expected as high pressure builds over the Western U.S.
Alan Smith, Meteorologist
