National Weather Service Forecast Discussion

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806
FXUS65 KBOU 280528
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1028 PM MST Tue Jan 27 2026

.KEY MESSAGES...

- Mild and dry through Wednesday.

- Light snow for the northern mountains Wednesday evening into
  Thursday morning, with scattered but generally minor travel
  impacts.

- A shallow cold airmass may backdoor into northeast Colorado on
  Friday, with a chance of light snow over the far northeast
  plains.

- Mainly dry and mild weather this weekend through Monday. Next
  chance of precipitation toward Tuesday or Wednesday of next
  week.

&&

.DISCUSSION /Through Tuesday/...
Issued at 130 PM MST Tue Jan 27 2026

Upper level ridge axis will shift east across the state late
tonight and Wednesday, before the next disturbance arrives by
Wednesday evening. This particular system is working onto the west
coast this evening, and will weaken as it moves into the ridge
axis. That means only limited moisture will be available by the
time it reaches Colorado. Nonetheless, at least there will be some
light snow for the mountains with sufficient orographics and
modest lapse rates. It should start very late in the afternoon or
evening Wednesday in the Park Range, and spread to the Front
Range Mountains and Summit County through the evening and
overnight. Then snow diminishes Thursday morning with drier air
arriving for the afternoon. Total accumulations are expected to
stay light since moisture is lacking, but thinking 1-4" is still
on track for the mountains along and north of I-70, with the
higher end in the northern tier of CO mountains.

Mild temperatures and relatively light winds can be expected on
the plains, but we do expect a pretty healthy deck of high clouds
to overspread the area. Thus, temperatures will be kept from max
warmup potential, but they should still be well above normal and
reach the mid 40s to lower 50s, with the cooler spots in valley
locations where inversions will be hard to overcome due to the
clouds. For Thursday, there is only slight cooling expected
behind the weakening shortwave.

For Friday, a backdoor cold front is still expected to arrive in
the afternoon, but most of the day (except in the northeast
corner) should still be mild with high temperatures at or above
normal. The weak front will offer up some shallow upslope and a
chance of light snow or flurries, but mostly on the northeast
plains. That front is quite shallow so most models agree the
cooling will be short-lived.

Above normal temperatures are expected to return this weekend
with dry conditions persisting under a large ridge of high
pressure centered to our west. We do see an opportunity for some
snow toward Tuesday of next week when a trough arrives, but there
is considerable uncertainty as to how that evolves. Thus, we`ll
stay in the middle of model guidance with just slight cooling and
a chance of precipitation toward Tuesday.

&&

.AVIATION /06Z TAFS through 06Z Thursday/...
Issued at 1026 PM MST Tue Jan 27 2026

VFR through the TAF period. Drainage winds have developed over the
last couple of hours and should continue into Wednesday morning.
Light and variable winds are expected Wednesday afternoon,
followed by a return of west or northwest winds by the evening
hours. Drainage flow looks unlikely Wednesday night as
west/northwest winds continue through most of the overnight hours.
A gradual increase in mid/high cloud cover is likely through
Wednesday night.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

DISCUSSION...20
AVIATION...Hiris

NWS BOU Office Area Forecast Discussion