A complex, wet and warm weather pattern for the weekend: heavy rain for southwest CO

10/07/25 8:30pm: Good evening. Wanted to give you a little update on what is looking like a complex and interesting weather pattern for the weekend with some deep and warm tropical moisture moving up from the southwest on Fri/Sat eventually combining with a fast moving short-wave trough and cold-front coming out of the northwest on Sun am.

Overall biggest impacts expected in southern CO (San Juans to Elks) and also parts of western Colorado near Grand Junction.

What I wanted to highlight is there is a chance for some very heavy rain, flash flooding and mudslides possible for areas in/near the San Juans and parts of Western CO from 3am Fri through 12pm Sun. Models show 1-3" of rain in that area (including Durango, Telluride, Silverton, Montrose, Pagosa Springs, Wolf Creek, Crested Butte, Grand Junction, etc). I circled this area on the first image below.

As I mentioned this big moisture surge will be coming from the remnants of hurricane Priscilla and will impact CO from 3am Fri to 3pm Sun with biggest impacts from Fri afternoon through Sat afternoon.

This is a warm surge of moisture for October, snow-levels will actually be at or above 13k ft through Sat pm so very little snow accumulation for the mountains until Sun am (that is strange for Oct).

Then a cold-front is expected to move across north-central CO late Sat night into Sun pm (3am-3pm Sun) this will change rain to snow in areas over the central mountains, early Sun am, lowering the snow-level to 10k ft with some minor accumulation in spots, 1-4" for parts of the north-central mountains.

For the north-central mountains around Eagle, Summit, Grand, ClearCreek, western Boulder/Larimer counties, etc less impacts overall but still some rounds of rain at times starting Fri afternoon, but better chances Sat afternoon into Sun. Then some rain/snow Sat night into mid-day Sun... so overall cloudy at the minimum and unsettled this weekend, but heaviest rain will be from say Aspen south and west.

For Den/Bou also not a great setup for much rain, but looks like a chance on Fri afternoon as the first surge of moisture moves through so a chance for weak thunderstorms and rain showers from 12pm-6pm on Fri. Then possibly some more showers on Sat afternoon (2pm-8pm) but it will be hit or miss, models don't show much measurable precip.

Then some gusty showers with the cold-front on Sun am to mid-day, but likely not much precip, just cooling down again (and windy)

Looking ahead, the models are all over the place for next week but in general looks active. Maybe another surge of tropical moisture from the south on Sun afternoon into Mon...

Then possibly some colder storm systems around Oct 16th-20th but hard to pin down any details....eventually some better snow chances coming up for the later part of Oct.

That is all for now.

First image shows forecast total liquid precip from now through 6am Mon (10/13) from latest ECMWF (has been the best model lately), I highlighted the areas with biggest impacts. Second image is equivalent from NWS Blend of Models, third image loop shows the evolution of the pattern via forecast precip-type/rate, mslp.