Our high of 98ºF yesterday will be in the rear-view mirror quickly today. A big airmass change is coming, with a temperature change in the valley of about 30ºF relative to yesterday.
The coldest air is presently over eastern and central Nevada. Yesterday afternoon our 700-mb (free atmosphere crest-level) temperature was +16ºC, but the airmass behind the front over western Nevada is about -8ºC.
That "super cold" air will just miss us, passing to the north, but we still expect 700 mb temperatures this afternoon to be almost 20ºC lower than yesterday.
The leading edge of the cold air at the surface is pushing into the Salt Lake Valley this morning. It hasn't reached campus as of 0850 MST, but it is close. Notice the 58ºF ob at Gunnison Island in the north arm of the Great Salt Lake. BRRRRRR.
Frontal passages are less frequent in June than earlier in the spring, but they tend to produce very large airmass changes. Today will provide a great example.