750
FXUS65 KBOU 290955
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
255 AM MST Sat Nov 29 2025

.KEY MESSAGES...

- Coldest air of the season will stick around through Monday
  morning.

- Areas of light snow and travel impacts will mostly end by the
  mid morning hours.

- Another round of light to moderate mountain snow expected
  Sunday/Sunday night, with smaller chances of lighter snow for
  the lower elevations.

- Slightly milder and mostly dry Monday/Tuesday. Then another
  potential shot at wintry precipitation Wednesday into Thursday.

&&

.UPDATE...
Issued at 255 AM MST Sat Nov 29 2025

Sharp cold front had moved through Denver and most of the plains
in these early morning hours. In the mountains, snow showers had
been heavy at times starting late last evening, with most
indications as of 3 am seeing 2-5" but locally 6-8+ in the
northern Gore and Park Ranges. Once the current frontal
enhancement moves through, the high country snow will taper down
through the rest of the morning as drier air moves in. We`ll keep
the Winter Weather Advisory for the ongoing impacts into early
this morning, but additional accumulations from this point forward
will be less than 3 inches. As discussed yesterday, this arrival
of drier air and strong mid level subsidence will be the limiting
factor of snowfall in the plains, despite a shallow post-frontal
upslope component. We do think at least flurries and areas of
light snow will occur in most locations in the pre-dawn hours
based on upstream observations, satellite imagery, and still some
mid level moisture around. I am leaning slightly toward a light
measurable snowfall in the pre-dawn hours, whether it be 0.1 inch
or locally up to 0.5-1.0" under a narrow band of slightly heavier
snowfall. It won`t measure everywhere, but we think there`s
slightly better than 50/50 odds at this point considering the
shallow upslope component - with the highest odds setting up from
Boulder/Denver onto the adjacent plains of east central Colorado.
The airmass dries very quickly starting about 14Z so we should
see a quick end to any light snow. The hazardous travel conditions
in the mountains will improve with the end of snow and return of
partial sunshine. Meanwhile, plains locations that see measurable
snow will also see some slick spots, but once sun is up for a
couple hours we should see sufficient solar insolation to
melt/quickly dry roads where it does snow.

Regarding temperatures, winter arrives today with high temperatures
staying at/below the freezing mark for the eastern plains. Return
of sunshine (still a few high clouds) should help a few spots get
just above freezing - mainly in the Denver to Ft Collins
Corridor. Lows tonight will plunge into the single digits and
lower teens in the lower elevations, with single digits much of
the mountains. We`d have higher confidence of colder temperatures
if were to be clear tonight, but appears slowly thickening high
clouds will have some impact on low temperatures. Something to
watch.

The remainder of the forecast looks relatively unchanged from
yesterday, with the next snow event beginning in the mountains
Sunday, but struggling to spread onto the plains Sunday evening
and night. Yet another chance of light snow still in the cards
toward Wednesday, but once again it looks like a minimal event for
any of the lower elevations.

&&

.DISCUSSION /Through Friday/...
Issued at 1234 PM MST Fri Nov 28 2025

Radar is showing the first few signs of elevated showers
developing upstream over the high country north of I-70, although
water vapor imagery looks rather lackluster thus far. Nonetheless,
light snow showers will gradually increase in frequency over our
northern mountains we enter our evening hours in particular, with
the bulk of the snow from this upcoming system anticipated to fall
overnight into early Saturday morning. The story impact-wise will
remain focused over our high country, where a relatively
widespread 3-6" of snow is expected to create hazardous travel
conditions across the majority of our mountain passes into the
morning hours. Locally favored west-facing slopes in our northern
mountains (mainly north of I-70) may approach 8".

Meanwhile, the lower elevations will be grasping at straws to see
any accumulating snow whatsoever, as has seemingly been the case
throughout the fall. There are two windows of opportunity for
light showers; the first will be late this evening as the left
exit region of the fast-moving jet streak zips overhead, and mid-
level moisture spills east of the Continental Divide. If (and it`s
a fairly large "if") any showers do develop, they`d more likely
bring a wintry mix, with near zero potential for snow accumulation.
Following that, the second window arrives in tandem with the cold
front, still slated for the early morning hours. Potential for
showers appears marginally higher then (closer to 60% chance), and
would certainly be in the form of snow with a sharp frontal
temperature drop, but we will be hard-pressed to squeeze out much
more than a dusting to half inch of snow if those materialize,
with ~1" still being close to the absolute maximum (and certainly
not widespread). The trend, per usual, is not in favor of snow.
Although a few localized slick spots may be found early morning,
the morning commute should be largely unaffected for most urban
corridor locations. So the ultimate question: Will Denver break
its snowless fall streak tonight? It`s genuinely a coin toss.

What the front will be lacking in moisture, it will make up for in
winter-like temperatures, and Saturday`s highs will be
approximately 30 degrees colder than today`s, remaining near or
slightly below freezing for the plains and I-25 corridor.
Overnight temperatures will fall to their lowest values so far
this season, registering in the single digits and low teens for
mountain and plains communities respectively.

The cold airmass will stick around for a little while as we see a
second, more tilted trough dig south over Colorado. Despite its
more amplified nature, the spatial pattern in accumulating
precipitation looks quite similar to the first system - light to
locally moderate snow accumulations in the mountains (generally
less than that received tonight) Sunday and Sunday night, with an
increasingly unimpressive chance (~30-40%) for light snow showers
spilling into the lower elevations. Perhaps the best potential for
minor accumulations outside of the mountains would be for the
Palmer Divide where there will be a slightly more favorable weak
upslope component, but the latest ensembles are not overly excited
for the measurable snow potential elsewhere. Regardless, we`ll
hold on to cold temperatures hovering right around the freezing
mark during the day, and returning into the teens or even a few
single digits Sunday night.

The Monday into Tuesday timeframe will be characterized by gradual
warming (slight on Monday, more substantial for Tuesday) and
generally dry conditions, outside of a small chance (~25%) of a
few mountain showers showers later Tuesday ahead of another
potential troughing pattern. It`s worth noting that there is
little agreement in the progression of the upper-level early to
mid-week, with some guidance signaling a more progressive
shortwave with varying tracks, and others favoring development of
a closed or cutoff low over California. Ensemble mean solutions
are thus the best way to go at this time, which would favor a
return to cooler and potentially "wetter" conditions (please note
the inclusion of quotation marks here) for Wednesday and perhaps
into Thursday. Approximately 70-80% of members carry snowfall
accumulations into our mountains for mid-week, with that
proportion falling to around 50% for our lower elevations.

&&

.AVIATION /06Z TAFS through 06Z Sunday/...
Issued at 1059 PM MST Fri Nov 28 2025

Cold front is on its way. Look for a period of gusty N/NE winds
to 25-30 kts and a quick development of MVFR ceilings with frontal
passage 0830Z-10Z from north to south across the Denver area TAF
sites. Areas of light snow/flurries are also expected, but only a
dusting to one half inch of light snow possible between 10Z and
14Z, before ceilings quickly dissipate by 17Z. Lighter but still
breezy northeast to east winds 10-15 kts expected by 14Z,
gradually transitioning to east and southeast 21Z-03Z. Possible
cyclone development after 06Z with winds becoming VRB or light
southwest depending on exact location of cyclone development.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 8 AM MST this morning for COZ031-
033-034.

&&

$$

UPDATE...20
DISCUSSION...BRQ
AVIATION...20