National Weather Service Forecast Discussion

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849
FXUS65 KBOU 261156
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
556 AM MDT Mon Oct 26 2026

.KEY MESSAGES...

- Rain ending from southwest to northeast this morning, with
  clearing skies this afternoon.

- Snow wrapping up across the mountains, but some minor travel
  impacts may linger through sunrise.

- Warming trend and mostly dry much of upcoming week.

- Unsettled weather potentially returning next weekend, but odds
  favor western and southern Colorado once again.

&&

.UPDATE...
Issued at 235 AM MDT Mon Oct 26 2026

A couple of quick updates this morning. First, it`s pretty clear
this wave is going to give many in the Denver metro more rain than
originally promised. Despite an absence of any real upslope flow
on the KFTG VAD, we`ve seen precipitation blossom across the
Denver metro and Palmer Divide since midnight. There`s been a few
public gauges that have already received 0.25" or so since
midnight across the far southwestern metro, perhaps enhanced a bit
by the northerly surface flow. Most of the precipitation is tied
to the strong vort max pivoting almost directly over the area this
morning, which guidance has struggled to handle. We bumped up
PoPs/QPF quite a bit in the near term to account for this. It
wouldn`t be surprising to see a couple half inch rainfall totals
by the time most folks wake up later this morning.

Given the changes in the precipitation and low level moisture
fields, it`s also likely that stratus will be slower to erode than
previously thought. We lowered high temperatures this afternoon by
around 5 degrees to account for this, though some recent guidance
(e.g., 06z HRRR) barely manages to get anyone into the 50s this
afternoon. With the cooler/wetter trend for today, that also
leads to a potentially foggy scenario for tonight into Tuesday
morning. Will let the day shift take a full look at this but it
wouldn`t be surprising if we ended up with some dense fog across
the northern metro and I-76 corridor.

&&

.DISCUSSION /Through Sunday/...
Issued at 1152 PM MDT Sun Oct 25 2026

Current radar imagery shows ongoing light showers across the
forecast area as the upper level shortwave tracks across
Colorado/Wyoming tonight. Mountain snow and rain showers over the
plains will continue through tonight before exiting the region by
Monday morning (most precip in Denver should be finished by sunrise,
with the northeastern plains still seeing showers in the early
morning). In terms of snowfall amounts across the high terrain,
forecast looks to remain on track, with the northern mountains
receiving generally 1-4" of snow by Monday morning and I-70 Corridor
and south receiving T-2". Expect travel impacts across high
mountain passes for the morning commute.

With low-level moisture still in place, many people will wake up to
fog/low clouds in the morning across the Denver metro and plains,
with possible impacts to morning commute due to low visibility.
However, expect conditions to gradually improve by 9-10 AM with
clearing skies in the afternoon. After that, an overall drying trend
is expected as the upper level shortwave exits the region. We will
still be relatively cool on Monday, given the slow morning warm-up,
with highs in the upper 50s to low 60s.

Relatively dry and quiet conditions are expected for the forecast
area Tuesday and through the end of the week, as more zonal flow
aloft returns. An upper level low in the Pacific Northwest is
progged to travel east across Idaho and Montana early this week.
While it will stay north of Colorado, it will bring increased
westerly flow aloft, resulting in breezy conditions across the high
terrain Tuesday. Short-range models have been hinting at winds
gusting up to 40-50 mph periodically in the morning. In terms of
temperatures for the week, ensemble solutions are in good agreement
of above-normal temperatures, with highs in the mid-to-high 60s
across the plains.

High uncertainty remains in the forecast Friday and into the
weekend. A weak upper level shortwave will track across the
southwestern United States and into the Central United States.
However, recent global model runs continue to hint that this
disturbance will likely be too far south and east to impact our
forecast area. For now, NBM PoPs of 10-20% seem reasonable at this
time for the eastern plains on Friday, but wouldn`t be surprised if
it continues to lower in the coming days. After that, models vary
drastically in handling the next upper level low that pushes through
by the weekend/ early next week. It will likely be able to tap into
tropical moisture as it tracks east into the Central United States,
but there is still high uncertainty which areas will receive the

&&

.AVIATION /12Z TAFS through 12Z Tuesday/...
Issued at 550 AM MDT Mon Oct 26 2026

Storm system is lifting out of the region this morning. Some
scattered showers and mist at BJC/DEN, which should persist for a
couple more hours. Ceilings vary quite a bit between ~300-1000ft
AGL, but should slowly start to rise beyond 14-15z this morning.
Should see a transition to MVFR close to 18z, but it could be a
few more hours until we return to visuals at DEN where a SCT/BKN
deck may linger. North winds this morning should eventually turn
to a light easterly component this afternoon.

Winds will attempt to go to drainage during the evening and early
overnight, but most guidance develops a weak Denver cyclone, with
fog and low stratus wrapping around the north/west side of the
cyclone. Overnight guidance continued to be bullish with this
potential, and soundings in general favor FG over stratus during
the morning hours. Have introduced a TEMPO for FG at BJC/DEN with
lower confidence at APA.

Given how much models have struggled with the pattern the last 48
hours or so, this is a slightly lower confidence forecast. Will
need to watch model trends closely today for both the erosion of
stratus late morning/early afternoon and for the FG potential
later on.

&&

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

&&

$$

UPDATE...Hiris
DISCUSSION...MAI
AVIATION...Hiris

NWS BOU Office Area Forecast Discussion