The late morning and early afternoon models have delayed the onset of the heavier precip and thunderstorms until this evening. Until then showers should be a little spotty.
We are in between a cold front o the east and a couple shortwave troughs to our east. The cold front brought temperatures down to the single digits this morning near Denver (8 in Castle Rock). It has retrograded nearly all of the way here, although the coldest air will remain to the east the short waves are headed this way. This time of year when cold air meets warm moist air, which is currently in southern Utah and Northern Arizona, thunderstorms occur. The timing may have been off slightly this morning but all of the ingredients will be present soon.
As you see there is significant energy to our west and we are in between the systems.
These are all lightning strikes over the last hour (3:15-4:15pm)
It could get interesting.