Denver (BOU) — the National Weather Service forecast in plain English · Plaincast

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Chilly but clear through tonight, and another freeze north and east of the Denver metro area.

Mainly dry and warmer for the weekend through the middle of next week.

Next storm system will arrive late next week with an increasing chance of showers and mountain snow.

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A rather chilly day is unfolding despite full sunshine. Clear skies, light winds, and a dry airmass will allow strong radiational cooling tonight, with below freezing temperatures expected over most of the northeast plains again. Meanwhile, we'll see a light downslope component develop along the Front Range keeping most of Denver/Boulder areas a few degrees warmer. Most locations northeast of Denver observed a hard killing freeze last night (deemed as 28F or colder), so from this point forward we will only be issuing highlights for those areas where a killing freeze did not occur - namely the I-25 Corridor and far northeast corner of the state. That means a Freeze Warning for Sedgwick and Phillips Counties tonight where lows are expected to dip into the mid to upper 20s.

For Saturday, an upper level ridge will build overhead with sunny skies and dry weather. Temperatures will be warming with highs pushing into the upper 60s to mid 70s, a few degrees above normal. Overall, another day of light winds can be expected with high pressure in control. There will just a slight increase of southerly winds over the eastern plains, resulting in localized elevated fire weather conditions mainly over Lincoln and Washington Counties.

On Sunday, the upper level ridge axis will shift eastward with light southwest flow aloft developing. This supports a continuation of above normal temperatures, with highs pushing into the 70s again across most of the plains. Enough mid level moisture gets caught up in this flow to warrant a low chance of showers in the mountains by Monday and Tuesday. That chance of showers may very well increase Wednesday, depending on how much tropical moisture pulls northward in advance of the next trough digging southward off the West Coast.

We are watching the arrival of this next storm system for the latter portions of next week, when the West Coast trough pushes east across the Rockies. There is considerable uncertainty this far out, especially as latest ensembles and operational runs are diverging from recent runs, splitting off a lead shortwave across the Central Rockies and Colorado Thursday or Thursday night, with a lingering trough holding farther west through next weekend. With more splitting being shown, the chances of significant precipitation in our forecast area have decreased. The highest odds now favor southwest Colorado once again as many of the storms have so far in September and October.