National Weather Service Forecast Discussion

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735
FXUS65 KBOU 281941
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1241 PM MST Sat Feb 28 2026

.KEY MESSAGES...

- Cooler Sunday with a few light mountain snow showers (limited
  impacts).

- Warm and dry Monday, with potential for locally critical fire
  weather conditions south of I-70.

- Mountain snow and low-elevation rain likely (80% chance) Monday
  night into Tuesday, favoring areas roughly north of I-70.

- Additional opportunities for precipitation through late week.

&&

.DISCUSSION /Through Saturday/...
Issued at 1121 AM MST Sat Feb 28 2026

The month of February is wrapping up like it started, in
other words mild and dry, and with today`s highs climbing well
into the 60`s, it`ll go into the books as one of our warmest on
record (3rd for Denver, 2nd for Boulder, and warmest on record for
Fort Collins). As far as weather is concerned, lingering pressure
gradient-driven winds continue to produce breezy conditions in
our foothills and close to the Wyoming/Nebraska state line, with
gusts 30-45 mph and ongoing critical fire weather conditions for
our northernmost plains counties. Elsewhere though, it`s a much
calmer day with a pronounced anticyclonic circulation keeping
lighter east flow in place away from the Cheyenne Ridge. Pressure
gradients (GJT-DEN) have weakened by ~1mb over the past couple of
hours, and will continue to do so through this evening.

Speaking of this evening, a weak backdoor cold front will fill in
from our east, helping to usher in cooler air for Sunday with more
widespread (albeit light) easterly flow anchored in place. Highs
will thus fall by 6-10 degrees for the lower elevations, with a
more subdued trend in the high country. Aloft, a subtle shortwave
will advect increased moisture into the region, providing for
greater cloud cover and supporting light snow showers across the
higher mountain elevations Sunday. These will bring little in the
way of accumulation, given a lack of synoptic support (QG
subsidence in place) and relatively weak orographic flow.
Additionally, temperatures are set to keep snow levels above
9,000-10,000 ft through the day. This will reduce snow ratios and
impacts, with accumulations of a dusting to 2" for most areas, or
as high as 3" for favored northern mountain locations.

Monday, an upper-level low will push into the Intermountain West,
with increased southwest flow along the leading edge of the
trough. The subsident flow regime will promote warmer
temperatures, and much of the lower elevations look to break 70F
under dry conditions. Areas roughly south of I-70 are favored to
be breeziest given their proximity to the modest jet core, and we
may see locally critical fire weather conditions develop as a
result, mainly across the far southern foothills and the Palmer
Divide into Lincoln County. Headlines may need to be considered if
current trends hold. Late in the day, the northern mountains could
see enough moisture move in for a few light snow showers.

The upper low is poised to drift over Colorado as an open wave
Tuesday, bringing our best shot at widespread precipitation in
quite some time. Areas north of I-70 will be better positioned in
terms of precipitation chances (over 80%) as well as for the
higher accumulations, but ample spread remains in QPF fields.
Mountain travel impacts can be expected for the northern mountains
in particular, where the probability of at least 1/4" (liquid
equivalent) is approximately 70%, but confidence decreases sharply
towards the I-70 corridor. For the lower elevations, temperatures
are anticipated to be too warm to support wintry precipitation,
outside of perhaps the Palmer Divide late in the day. Healthy
frontogenesis could support some localized bullseyes of greater
rainfall, but there`s limited agreement in the location of said
features still.

Ensemble guidance continues to suggest an active pattern over the
western CONUS for the second half of the week, favoring deeper
troughing to our west and potential phasing of low pressure
systems late week. Cluster analysis indicates significant
uncertainty however, driven in large part by timing and location
differences between ensemble members when it comes to the
progression of the potential cutoff low to our southwest. Thursday
appears to be the earliest that snow could return to our mountains,
with a majority of guidance delaying the onset of any such
chances for the lower elevations to Friday. Generally this window
favors a colder system and thus greater potential for snow for the
plains and urban corridor, but there are still a few failure
modes that would result in little to no precipitation.

&&

.AVIATION /18Z TAFS through 18Z Sunday/...
Issued at 1044 AM MST Sat Feb 28 2026

VFR conditions expected through the TAF period. Currently, a gusty WNW
and NE boundary are converging over KDEN, bringing gusty winds
from the west over the western half of the field, and lighter north
to northeasterly winds to the eastern portion. Low confidence in
wind direction over the next hour, but do have higher confidence
that lighter northeasterly winds will settle in in the next hour
or two. From then onward, winds should make an easterly transition
through the early afternoon, with a backdoor cold front delaying drainage
winds from settling in until around 8/9Z tonight.

For Sunday, a surface cyclone looks to form just north and east of
the TAF sites in the early morning. Current hi-res guidance shows
light WNW winds developing in the early morning before becoming
northerly to northeasterly in the afternoon. As with any cyclone
development, there is low confidence in wind direction as it may
change depending on exactly where the cyclone forms, though winds
are expected to remain fairly light under a fairly weak pressure
gradient.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning until 6 PM MST this evening for COZ238-242-248.

&&

$$

DISCUSSION...BRQ
AVIATION...9

NWS BOU Office Area Forecast Discussion