Forecast details for the approaching double-barreled storm system: good storm chances Tue and Wed

09/16/25 8:15am: We have a couple of active weather days on tap as double-barreled trough moves through. Already some thunderstorms over northeast CO this morning from Longmont to Greeley. Also some rain moving into northwest CO closer to Steamboat.

Initially the focus for heaviest rain (and snow above 11kft) will be over the northern front-range from Boulder, through Ft. Collins to the WY border and also across parts of the northeast plains. In the mountains: Front Range mountains along/east of the Cont. Divide will be favored.

On Wed the focus for heaviest rain will be across the southern front-range, from Springs to Pueblo, etc.

It will be much cooler and cloudier on the front-range (Den/Bou) both Wed and Thu. Here are some forecast details:

For Den/Bou and the front-range

• For today rounds of scattered storms from 2pm-11pm, best chances as the first main wave moves through: 5pm-10pm, best storm coverage around the edges (from Boulder north, in/near the foothills, and from Palmer Divide to Colorado Springs)

• After 3pm there will be some strong to severe storms over the northeast plains (mostly east of a line from Akron to Limon): medium-sized hail, heavy rain and wind will be the main threat (and maybe an isolated weak tornado)

• For tomorrow, cool and cloudy in the morning, then a chance for some storms in the afternoon: 2pm-10pm again...but on Wed best coverage will be from Denver south and especially PD to Springs and southern front-range (where the main cold-front stalls out)

• Some rain may continue overnight into Thu am (foothills will be favored)

• Thu will start cool and cloudy but give way to sunnier and drier conditions in the afternoon

For the north-central mountains:

• Some rain showers over northwest CO this morning

• Then a chance for isolated to scattered thunderstorms from 1pm-9pm, best chances 3pm-7pm, best coverage from Summit Co east

• For tomorrow (Wed) some scattered storms again but mostly for the Front Range mountains (along/east of the Cont. Divide) from 2pm-10pm. West of the Tunnels, just very isolated storms on Wed

• A chance for some light snow in spots both tonight into Wed am and again Wed afternoon into Thu am, favoring the northern Front Range mountains: IPW, RMNP to Cameron Pass could get 1/2" to 4" in a few spots above 11k ft by Thu am. Further south and west (near Summit Co, etc) likely not that much (Trace-2" in a few spots up high)

• It will remain chilly into Thu am and then it dries out and warms up

• Looking like a nice weekend in the mountains for some leaf peeping from Fri-Sun with mostly sunny skies, seasonable temps and very little chance for any storms (should be great)

  
  

First image loop shows forecast radar over the next 48hrs (6am this morning through 6am Thu) from latest HRRR. Second image shows the double-barreled trough (you can see the two areas of low pressure) at 6pm Wed. Third image is current local satellite/radar/surface overlay showing the morning showers. Fourth image shows the severe weather outlook for today from SPC. Fifth image shows forecast total liquid precip from now through 6am Thu from latest HRRR, take with a grain of salt but shows where the focus for heaviest precip will be in the next 2 days.