Complicated forecast shaping up for next week, starting Sat as remnants of hurricane Rachel interact with some west-coast troughs.

10/07/26 9:30am: Heads up the forecast is looking all kinds of complicated next week and into that following week as some west coast troughs / upper-level lows are forecast to interact with remnants of some of the hurricanes (like Rachel and tropical depression 20, which will also be a hurricane soon). And these features will also combine with some cold-fronts at times to make it even more complicated.

These interactions are going to create a challenging and uncertain forecast (don't believe your phone apps for next week, or the following week, the forecast is changing daily).

Initially looks like remnants of Rachel are going to move up into parts of CO from Sat afternoon, through Sun into Mon, with biggest impacts on Sun.

Moisture, thunderstorms and rain increases across the mountains on Sat (favoring southern CO).

Then potential more wet, cloudy cool with on/off rain showers and thunderstorms over much of the mountains on Sun into Mon, again favoring southern / western CO for heaviest rainfall. Some snow above 13kft.

The setup for Sun/Mon is not great for rainfall on the front-range (Den/Bou) though, so likely just turning cloudy with a slightly better chance for rain each afternoon (Sat and Sun) but likely not much actual precip initially.

The most unsettled weather coming up: cooler with better rain/snow chances across the entire state will be from Tue-Sat (Oct 13-17th), maybe multiple storm systems and cold-fronts. Mountain snow will be likely, especially towards the end of next week. You can also see the pattern change in the Boulder meteogram (image 3 below).

First image loop shows the evolution of the pattern via forecast 500mb heights / vorticity from latest ECMWF over the next 15-days (look how wild it gets in the west next week and the following week). Second image shows forecast mslp, precip-type/rate at 12pm Sun (showing the big surge of moisture from Rachel). Third image shows Max/Min 6Hr 2M Temp. + QPF + Snow for Boulder over the next 15 days from ECMWF, you can see the temperature changing and much better precip chances after Oct 13th... fingers crossed.