The "frontal passage" shows up quite nicely at Gunnison Island on the Great Salt Lake. Not a huge temperature drop, but abrupt nonetheless.
Nevertheless, there's plenty as well to be confused about. Note the northwesterly flow at Dugway Proving Grounds, yet temperatures are in the mid 50's? Looks like the temperature gradient and wind shift may not be collocated. Simplistic views of frontal evolution may not apply to this case.