JACKSON, Wyo. — Over the past week, we saw a transition into an “afternoon and evening thunderstorm” pattern that had been lacking over the first three weeks of July. Overall, rainfall amounts were not overly impressive, but we at least received some moisture after an extended dry spell.
Rainfall amounts ranged from 0.1 to 0.3 inches over the past week across Teton County, so we are still well below average in terms of rain for the month of July. Fortunately, we have not had any significant wildfires locally yet as vegetation fuels are still relatively moist for this time of year. That may also explain why the bugs have been so bad this summer!
Over the past week, temperatures were right around average for late July. The warmest temperature of the week at the Jackson Hole Airport was 84 last Tuesday, and the coolest temperature was 40 on Saturday and Sunday.
Widespread showers and thunderstorms expected on Tuesday (and to a lesser extent Wednesday)
The week will start with beautiful weather on Monday, but a potent disturbance will bring more active weather on Tuesday and Wednesday with widespread showers and thunderstorms. Highs on Monday will reach the mid 80s and no rainfall is expected with any storm chances confined to areas south of Teton County.
Changes will arrive overnight and on Tuesday as a disturbance containing subtropical moisture arrives from the southwest. Isolated showers and thunderstorms will become possible on Tuesday morning (chances existing prior to sunrise) before more widespread showers and thunderstorms develop by late Tuesday morning and continue into the afternoon and evening.
We could see some heavy downpours on Tuesday with rain amounts of up to half-inch or more possible across the higher elevations. Be prepared for soaking rains and elevated lightning potential if you’re spending time outdoors on Tuesday. Temperatures will also be much cooler on Tuesday as well given the abundance of cloud cover.
The weather will start to improve some on Wednesday with a generally quiet start to the morning expected, but enough lingering moisture will result in scattered afternoon thunderstorms developing. Steering winds will shift on Wednesday meaning that storms will approach from the west/northwest instead of from the southwest.
Hot and dry conditions arrive late this week and into the weekend
The pattern will dry out significantly toward the end of the week as a ridge of high pressure builds over the Rocky Mountains. This will likely result in our hottest temperatures of the season from Friday through the weekend with highs in the upper 80s to near 90 in the valley.
The dry pattern will continue into the first week of August with minimal rain chances while temperatures should continue to run warmer than average.
Alan Smith, Meteorologist
