483 
FXUS65 KBOU 261825
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1225 PM MDT Mon Oct 26 2026

.KEY MESSAGES...

- Areas of fog across the plains tonight through Tuesday morning.

- Warming trend and mostly dry for 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 /18Z TAFS through 18Z Tuesday/...
Issued at 1215 PM MDT Mon Oct 26 2026

Current GOES-19 satellite imagery shows the stratus deck that
affected the sites this morning breaking up with the south metro
(KAPA) seeing the most improvements so far. Still, with the 
saturated ground from the overnight rainfall/mist and low-level 
moisture, clouds will have a difficult time fully scattering out 
this afternoon. Therefore, we expect a sct deck around 1500 ft AGL
to 3000 ft AGL through mid-afternoon, but some improvements look 
possible as we get to late in the afternoon. KAPA should have 
fewer clouds than the other two sites. Winds this afternoon will 
turn to the east and should remain under 12 kts.

Another night of fog is looking increasingly likely (>70%) at 
KDEN and KBJC with 50/50 odds at KAPA. BUFKIT and model soundings 
continue to point to saturated low levels with dewpoint 
depressions at or under 1 degree. A Denver Cyclone is progged to 
develop to the north of the three sites this evening and move off 
to the northeast. This would cause a westerly component to the 
wind at all three sites with light and vrb winds as we get into 
Tuesday morning. In turn, short-term guidance is in very strong 
agreement that fog could rapidly develop this evening as early as 
6-8z from north to south on the north/west side of the cyclone. 
The period of highest confidence at KDEN for visibility around 1/2
SM and IFR/LIFR restrictions is from 9z through about 14z. There 
is a ~30% chance that visibility could even drop as low as 1/4 SM 
with vv001 causing further restrictions. Generally, the same 
timing is expected for KBJC with only slightly higher 
visibility/ceilings than KDEN. At KAPA, winds could be a little 
more southerly (downslope), which would lower overall chances for 
impactful fog directly at the terminal. Otherwise, if winds do 
keep more of a westerly component, fog/low ceilings/lowered 
visibility are in play there as well.

The fog and low ceilings should start to lift by about 15z Tuesday,
but sct clouds around 1000 to 2000 ft AGL look to stick around 
for a few more hours. VFR conditions appear possible by 18-20z 
Tuesday afternoon as skies clear. Winds turn to the east for 
Tuesday afternoon before becoming vrb by the evening.


&&

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

&&

$$

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