5:30 AM MDT, Friday, May 17, 2019
The 80 degree days are over for at least 5-7 days. Two major storm systems will move through the Colorado/Wyoming region, one later today and tonight, and another early next week.
Today and tonight
It will still be near or a little above average in temperature today, but with a better chance for thunderstorms this afternoon and evening. The best chance for strong or severe thunderstorms will be on the far northeastern plains of Colorado, southeastern Wyoming, and in Nebraska. The lowest chance for thunderstorms is south of Denver.
Saturday and Sunday
Cooler weather with some showery periods possible, but for the foothills and plains it should be dry most of the time. In the mountains, the chance for showery periods is a little greater, and there may be some snow above treeline. The potential for clouds and precipitation increases a little late Sunday as the next storm approaches.
This could end up being a very cool and occasionally wet period, with substantial snow above 8000 feet and cold rain in the lower elevations. I’ll have to update on this later in the weekend. There is a small chance for damaging nighttime temperatures for tender plants, but it’s too early to tell yet.