Really perfect day out there, 85 currently which is probably our high following a low of 27, one of my largest June spreads ever. Really good snow conditions today for skiing, nice soft corn on south sister.
You’re correct about models overdoing heat/ridging in the west so far. You’re wrong about the Mexican/Gulf ridge not migrating into the US. It will reform in the eastern US next week.
You have to take a lower frequency approach to this. Sure, the heat ridge won’t be present 24/7, but it is the dominant background mode this summer. That doesn’t mean it’s the *only* mode, but it’s the leading one.
It will wobble around, it will take breaks every now and then. But it will likely dominate the mean state this summer, overall.
I did it last September! Walked right up to the summit in trail runners, didn't even touch snow. I'm guessing it was more of an adventure this time of year!
Expect widespread wet conditions with very cool conditions, winds
will turn northeasterly. Heavy, wet accumulating snow is expected
above 5000 feet, throughout southern Idaho County and most of
western Montana. In western Montana, above 6000 feet a trace to 14
inches is possible, while in the Bitterroot, Anaconda, and Pintler
Mountains, Bob Marshal Wilderness, and Glacier National Park
Region the highest terrain has a 25% chance of receiving 14 to 20
inches of snow. This amount snow accumulating on trees with
foliage could cause branches to go down on back country roads, be
prepared. Due to the high impact potential above 6000 feet and
moderate confidence of the event actually happening, winter storm
watches have been issued along Continental Divide from the
Canadian border through MacDonald Pass on I-90, including
Georgetown Lake and the Anaconda and Pintler Mountains. The main
snow event will be overnight Monday through Tuesday.
Similar events to this one, in June 2008 and 2001, produced a
small area of valley snow down to 2800 feet. There is insufficient
confidence in either low pressure track or intensity currently,
but you are encouraged to follow future forecasts as 1 to 2
inches of heavy, wet snow on trees with leaves could easily cause
broken branches leading to localized power outages with winter
driving conditions in area mountain passes.
MSO referenced June 2001. Bozeman got 18” from that storm. I moved there a few years afterward but heard stories.