Updated Thu Jul 14, 2022 4:00pm MST | Published Thu Jul 14, 2022
- Widespread thunderstorm activity today and Friday.
- Weak cold front overnight Friday.
- A little bit less activity on Saturday, but still significant. Some severe storm potential on the plains.
- Sunday should be notably less active, especially north of I-70. South of I-70, still isolated to scattered thunderstorm, decent activity likely in the San Juans.
- Overall uptick in storm activity for Monday, decreasing into the rest of next week.
- Likely another moisture surge the following weekend.
- Hot on Monday to Tuesday, another heat wave possible after Thursday.
Lightning Risk Grids
Hello everyone. We missed our forecast earlier this week as Thomas was writing for Seth’s Weather Report. You’ll have the advantage of not being privy to the ins-and-outs of trying to gauge the impact of a tropical disturbance in the Gulf of Mexico, as that has completely disappeared by this point and wont really be impacting our weather.
Over the past week, high pressure has lazily moved from our east to our west, crossing over Colorado. We have seen some spicy temperatures and drier conditions as it has moved overhead. Generally, the near term forecast has the center of high pressure over Utah, but recently the center has moved back towards Colorado, where it will remain into Friday.
Storms are rotating around this center of high pressure very slowly. On Friday, widespread flash flooding watches have been issued in Colorado as any storm cells will drop copious amounts of precipitation over small areas.
… and there will be plenty of storm cells on Friday! Winds aloft and near the surface are transporting monsoonal moisture into western Colorado. The atmosphere will have twice as much precipitable water as usual.
Despite strong high pressure over our region (which results in subsidence in the atmosphere, which can put a damper on storm development), models are expecting a shortwave to track across the area into Saturday, which should add some dynamic lift to the situation and aid storm development.
This will also drive a weak cold front into Colorado on Friday night – nothing serious, but should take the edge off the scorching temperatures we’ve been experiencing lately. Those high temperatures will return Monday and Tuesday.
Point is – Friday will be a very stormy day across much of Colorado, with multiple waves of slow-moving thunderstorms.
Saturday features more of the same, but with less moisture in the atmosphere, particularly in northern Colorado. Overall, a slight downtick in storm potential from Friday, but still quite considerable. It looks like severe storms may be a real possibility in the eastern plains of Colorado thanks to a boundary driven by the shortwave.
Subsidence and drier air behind that shortwave will make thunderstorm development more challenging on Sunday, but there’s still enough moisture and instability for isolated to scattered thunderstorm activity to occur. The best thunderstorm activity should be confined to the central and southern mountains – most areas north of I-70 will only see a few highly isolated cells at best.
High pressure starts to retrograde back west as a larger shortwave traverses the northern United States on Monday. Initially this will pump another round of moisture into western Colorado which will enhance thunderstorm activity on Monday and Tuesday. However, it will also transport some drier air southwards which some models think could enter Colorado by Thursday.
Generally, expecting thunderstorm activity to increase for Monday but taper off over the course of next week.
There should also be a heat wave associated with this, especially Monday to Tuesday and Thursday onwards. This heat would mostly impact areas east of the Divide, less so the mountains. Expect next week to be hot, overall:
Ensembles then suggest high pressure could track back eastward and draw in another surge of moisture into Colorado for the weekend, especially if low pressure develops over the Gulf of California as some models are progging. Plan for another difficult weekend in the mountains!
After that, the forecast for the last week of July still features good monsoonal moisture chances and hotter than average temperatures.