|Meteorologist Jim Woodmencey|
An unusually cold Low pressure system for late July moved across the Northern Rockies on Monday, July 27th, 2015 , bringing with it a dramatic drop in temperatures, and snow to the higher elevations of the Teton Range in western Wyoming, as well as some strong, gusty winds.
Snow was observed at the top of Teton Pass Monday evening, at an elevation of just over 8400-ft. Snow was on the ground down to around the 9500-ft. elevation on Tuesday morning in the Tetons. It is not especially unusual in the higher Tetons to have snow in July, however, to see it on the mountains to such a low elevation this time of year it is. Last summer it snowed down to about the same elevations in late August. So, we are a month earlier this year!
There were some strong gusty winds with that front, hitting 70 mph at the Lower Saddle (11,610-ft.), 54 mph on top of the JH Tram (10, 318-ft.), and 49 mph over on Lava Mountain near Togwotee Pass (10, 430-ft.).
The Jackson Hole Airport experienced wind gusts of 30 to 40+ mph between noontime and 3:00 pm. They maxed out with a 43 mph gust.
Temperatures dropped over 20 degrees in the valley as the front passed in the afternoon, going from a highs in the mid to upper 60’s around noontime to the mid to upper 40’s by 3:00 pm.
The low temp at the JH Airport Tuesday got down to 30-degrees. In town it was mid 30’s and not really threatening the record low of 31 degrees for July 28th, set back in 1940. The record low for July 29th is 27 degrees, and I have foretasted a low near 30 for Wednesday morning.
In the mountains temps went from a high near 70 degrees at 10,000-ft. on Sunday afternoon to highs in the upper 50’s at noontime Monday, then the temperature plummeted to near 30 degrees by 3:00 pm Monday afternoon. A 40-degree drop in about 24-hours!
At one point Monday evening at the Lower Saddle of the Grand Teton, the temperature was 25 degrees and the wind was blowing steady at almost 40 mph, causing the windchill factor to make it feel like 7 degrees. Yes, seven!
|Summary of Weather Events around Jackson Hole & the Teton Mountains for July 27th, 2015.|
Post by Meteorologist Jim Woodmencey