Colorado Weather Discussion #126: Sep. 28, 2021

Snow is falling at elevation, but uncertainty over final accumulations still remains.

This forecast is no longer valid. Please return to our list of forecast articles to find more recent posts.

Updated Tue Sep 28, 2021 11:00pm MST | Published Tue Sep 28, 2021

By Thomas Horner

Here are some more thoughts on our current forecast – please consult that for details, timings, and specifics.

This new blog platform we built is quite flexible and we are still working out how we are going to structure and update larger forecast articles while putting out smaller updates, nowcasts, and conditions reports, so bear with us.

As expected we saw widespread storm coverage flare up today as significant moisture associated with a closed low to our south advected into Colorado.

(via WeatherBell)
(via WeatherBell)

Weather satellites detected a decent number of lightning strikes across Colorado’s high country, but the most robust cells have been confined to the Western Slope, where a few storms are still active, such as near Grand Junction.

On Monday, the Ptarmigan wildfire started near Silverthorne and has resulted in 183 evacuations, growing to nearly 100 acres today. Luckily, our wetter and cooler pattern has been helping combat the fire today.

(via Twitter user ManofLeMooses)
(via Twitter user ManofLeMooses)

A cold front is still on its way tomorrow, and right now the warmer airmass in place over Colorado is keeping the snow level at about 12,000-13,000ft., which should drop to just above 11,000ft. overnight.

Current conditions show air temperatures at or just above freezing near 11,000ft, with similar dewpoints, indicative of some ongoing precipitation in spots, which is falling at snow above that altitude.

(via NWS)
(via NWS)

Pockets of precipitation are expected to continue overnight, especially in western Colorado.

(via Highpoint Weather)
(via Highpoint Weather)

Model guidance is still showing the potential for significant totals at higher elevations by the weekend.

(via Highpoint Weather)
(via Highpoint Weather)

For the northern and central mountains, most of this is front-loaded on Wednesday evening and Wednesday night, with only light precipitation expected Thursday and Friday afternoon/evening before our drier weekend.

(via Highpoint Weather)
(via Highpoint Weather)

For the San Juans and southern Sangres, we’re still looking at a stronger push of moisture and colder temperatures later in the week, though the timeline has moved forward a bit, with better precipitation chances as early as Thursday afternoon as opposed to Friday morning.

(via Highpoint Weather)
(via Highpoint Weather)

This isn’t a full-on winter storm, and snow liquid ratios will struggle to get much higher than 10:1.

(via Highpoint Weather)
(via Highpoint Weather)

Overall, the table of snow accumulations a few images above looks pretty sound to us – most likely, the higher peaks will pick up a few inches of snow (1-5”) but a few may get lucky and get several rounds of consistently heavier precipitation which could bump them up towards double digits. Snow totals will quickly fall off below 10,000-11,000ft, with the Blend still insistent that the snow level wont dip below 10,000ft.

Regardless, the mountains will have a fresh coat of paint by the weekend, when the fall colors should be peaking across much of the state.

For any more details, such as a day-to-day breakdown, check out the more detailed forecast article.

--

More frequent updates on Twitter, Instagram, and Facebook: @highpointwx


💙 Supported By 💙

  • Kim H.
  • Briana K.
  • Kevin M.
  • Cullen O.
  • Tal W.

We love doing this and making our work available for free! But it does take a ton of time to put these forecasts together, develop our custom graphics, and keep our servers running. Consider throwing some beer or coffee money our way: Support us on Patreon!


Shout out to our friends: Weather5280, Seth's Weather Report