389
FXUS65 KBOU 251200
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
600 AM MDT Sun Oct 25 2026

.KEY MESSAGES...

- Scattered rain and snow showers across the mountains into the
  morning hours, with rain showers over the eastern plains.

- A little warmer and drier during the day today, followed by
  another chance of rain and mountain snow late tonight into
  Monday morning.

- Minor travel impacts across the mountains over the next day or
  so... shifting to mainly the northern mountains Sunday night
  into Monday.

- Warming trend and mostly dry much of upcoming week, with
  unsettled weather potentially returning next weekend.

&&

.DISCUSSION /Through Saturday/...
Issued at 1227 AM MDT Sat Oct 24 2026

An upper level low continues to spin over southern Utah tonight.
Composite radar imagery across the state shows a few batches of
precipitation, mainly centered over southern and eastern Colorado
tonight. There`s also been some decent snow accumulation across
portions of Park county over the last several hours, with some
travel impacts noted across a few of the mountain passes in that
area. Some snow should linger through the night, though
additional accumulation there should be fairly light.

The upper low should continue its slow journey northeastward on
Sunday, leading to one last day of widespread rain and snow across
the region. While the track of this has remained consistent over
the last couple of days, there`s still a few parts of the forecast
that remain rather uncertain.

First, it looks likely that temperatures will be warmer across
the metro, as deeper stratus has failed to develop tonight... and
most guidance actually clears out the I-25 corridor as a Denver
cyclone develops in the morning. It wouldn`t be surprising to see
a few 60-65F temperatures during the afternoon hours before deeper
cloud cover redevelops. Second, there is considerable spread with
precipitation totals Sunday night into Monday. A strong vort max
is expected to rotate around the base of the trough, pivoting from
northwestern New Mexico into northeastern Colorado by Monday
morning. A weak surface low should develop in response to this,
but models place the center of this surface low as far west as
Greeley (HRRR) to as far east as Burlington by 09z Monday. Model
consistency in this period is nowhere to be found. The wholesale
mean solution would be for scattered rain/snow showers developing
over the northern mountains during the afternoon, with a more
organized precipitation shield developing north/northwest of the
surface low where stronger synoptic scale lift would combine with
deepening upslope flow. This likely ends up somewhere along our
northern tier of counties, with at least a chance (30-50%) of
some half inch rainfall totals near the CO/WY border.

Any precipitation left in the forecast area should quickly move
out of the area during the morning hours Monday, with clearing
skies and near normal temperatures expected.

The rest of the week looks rather quiet, with warmer and dry
weather likely under broad southwesterly flow aloft. High
temperatures should end up in the 60s to low 70s across the plains
most days. Some moisture could return as early as Friday or
Saturday as a weak shortwave moves through the region, though the
flow aloft would again favor the terrain to the west/southwest of
our CWA. Though details remain hazy, there are signals that the
storm track would remain fairly active from next weekend into
the first couple days of November.

&&

.AVIATION /12Z TAFS through 12Z Monday/...
Issued at 542 AM MDT Sun Oct 25 2026

Winds have stayed slightly more ESE at KDEN than expected through
the overnight hours, which has allowed for some lower ceilings to
return. There was a short period where KAPA backed slightly more
SE with the same outcome of lower ceilings around 4,000 feet AGL,
but has since been able to hold on to a more SSE component,
tapping into better downslope drying.

For today, a Denver Cyclone will bring lower than normal
confidence in the prevailing wind direction through the day today.
As usual with cyclones, depending on where exactly the
circulation develops will determine where the shear zone forms
that will have a southerly component on the southern side of it,
and a northerly component on its northern side. At this time, we
expect a period of light and variable winds to develop in the next
hour or two this morning at KDEN/KAPA, with KBJC likely holding
onto a northerly component for the remainder of the day. Exact
wind directions will be determined by the movement of the cyclone
throughout the day, but we do expect a northwest to northerly
transition sometime between 17-19Z. On the northern side of the
cyclone, northerly winds are expected to remain light through the
morning (under 9kts). Slightly stronger wind speeds are expected
on the southern side of the cyclone, where we could see prevailing
speeds between 10-14kts.

Late this afternoon and evening, an upper-level disturbance is
expected to move across Colorado that will bring precipitation
chances starting around 23Z-0Z through around 5Z tonight. The main
impacts from passing showers will be with lowering cloud decks,
which could lower to around 2,000 feet AGL, and potential for some
VRB15G20KT winds as showers pass. Beyond the shower potential,
ceilings are likely to continue to lower through the overnight,
with hi-res guidance showinG decent agreement on getting down to
IFR conditions through early Monday morning.


&&

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

&&

$$

DISCUSSION...Hiris
AVIATION...9

NWS BOU Office Area Forecast Discussion