Updated Thu Jun 30, 2022 3:00pm MST | Published Thu Jun 30, 2022
- Another very stormy weekend, with lesser impacts in the Front Range.
- Saturday looks slightly better than Sunday, but both days feature widespread thunderstorms in the mountains.
- Slight downtrend in storm coverage from Monday to Tuesday.
- Monsoonal flow looks to get pushed west as we progress into next week. By next weekend, thunderstorm chances near and east of the Divide could get more isolated.
- Likely very hot in northeastern Colorado that weekend.
Lightning Risk Grids
High pressure has broken down over the southern United States, but is starting to rebuild to our east, allowing for a surge of monsoonal moisture to enter the desert southwest.
As promised, moisture is in place once again over the Four Corners region. This, combined with a few small disturbances aloft, is driving widespread thunderstorm development, particularly in the mountains.
Guidance from the Euro ensemble shows ongoing northward transport of monsoonal moisture into our region as we progress into the start of next week:
This holiday weekend looks quite stormy across Colorado. Quite a lot of red on our thunderstorm tables that we posted above!
The “best” day may be Saturday as the atmosphere is a bit drier and a bit more stable behind a weak shortwave, but widespread thunderstorm development is still expected.
High-resolution modeling shows thunderstorms erupting across the high country every afternoon, with the western and southern regions of Colorado potentially seeing lightning by 11am.
The story will be much of the same into next week.
As we’ve seen, widespread storm coverage in the mountains does not necessarily translate to much on the plains and in the Front Range. The urban corridor has struggled to pick up decent precipitation, as storms from the mountains fall apart due to a consistent capping inversion over the lower elevations. The Euro model continues to show a donut-hole from Fort Collins to Denver:
Even the SREF-ARW ensembles members (which usually have a wet bias) have comparatively little precipitation over the Denver metro area. Denver is in the shades of light green directly southeast of the dark red blob in north-central Colorado:
Euro ensemble guidance supports this thinking:
In fact, areas that are expected to see the most consistent rainfall over the next few days have seen an improvement in drought conditions since last week:
Now they’re just getting greedy!
As we progress further into next week, high pressure to our east will continue to build and center itself more directly over Colorado.
This will move the best monsoonal flow to our west. It’s likely that the western mountain ranges, such as the San Juans, will still see elevated thunderstorm chances by next weekend, but near the Divide we may see a trend towards more isolated storm development.
It will also likely get quite hot in northeastern Colorado that weekend.
Though this pattern change isn’t as favorable for precipitation in Colorado, it doesn’t look like it will completely shut the door to moisture. Following next week, there looks to be some support for a return to cooler, wetter conditions, but that’s currently only a weak signal.