The rain showers from Wednesday and Wednesday evening are well to the east of Colorado.

We see from the black and brown colors on the water vapor satellite image that most of the atmosphere over Colorado is quite dry. And look at the strong storm swirling in the upper-left! That’s bringing snow to western Canada.

The key thing to remember about the water vapor satellite image is that it shows the amount of water vapor in the upper 1/2 to 2/3rds of the atmosphere. So even if the image depicts dry air, we can still have a lot of moisture near the surface.

And indeed that's the case on Friday morning as low clouds shrouded some of the eastern plains around Denver, Ft. Collins, and further south over Colorado Springs and Pueblo.

Aside from the eye candy provided by these low clouds on Friday morning, there will not be much going on with the weather during Friday, Saturday, or Sunday. Enjoy the sunshine and fall temperatures!

UPDATE: Just got word that Arapahoe Basin ran their snow guns last night. Details here: http://arapahoebasin.blogspot.com/2018/09/september-snowmaking.html

The forecast for the end of September is reasonably clear.

On late Sunday night through Monday, expect a fast-moving storm to bring a few showers and then cooler air will arrive behind the storm. The mountain peaks could get a dusting of snow from this system.

Following the storm, from Tuesday through the remainder of September, colder-than-average temperatures will stay near and east of the continental divide.

Precipitation will follow the general storm track, with the best chance for any showers near and east of the divide.

Is there any sign of significant snow soon? Not around here. The 10-day forecast shows that western Canada will continue to see moderate snowfall, but over the lower 48 states, the best chance for a dusting to a few inches will be near and east of the divide.

Looking far out, there is no clear signal from the 30-45 day forecast models about what to expect in early and mid-October. From experience, once we get a weather pattern like we’ll see starting next week, with cold air staying near and east of the divide, that pattern can last for a while.

So I am not holding my breath for a big mountain cool-down and lots of snow during the first 10 days of October. But forecasts beyond 7-10 days have very little skill, and it's that unpredictability that keeps us glued to the next updates from the models. Of course, I'll keep you updated!

Thanks for reading … next update on Monday, September 24!

JOEL GRATZ

OpenSummit

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Geography Key

Northern Mountains
Steamboat, Granby, Beaver Creek, Vail, Ski Cooper, Copper, Breckenridge, Keystone, Loveland, Abasin, Winter Park, Berthoud Pass, Eldora, Rocky Mountain National Park, Cameron Pass

Along the Divide
Loveland, Arapahoe Basin, Winter Park, Berthoud Pass

East of the Divide
Eldora, Echo, Rocky Mountain National Park, Cameron Pass

Central Mountains
Aspen, Sunlight, Monarch, Crested Butte, Irwin, Powderhorn

Southern Mountains
Telluride, Silverton – north side of the southern mountains | Purgatory, Wolf Creek – south side of the southern mountains