752
FXUS65 KBOU 061909
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1209 PM MST Thu Nov 6 2025

.KEY MESSAGES...

- Very windy today with a few gusts from 55 to 70 mph in the
  mountains and foothills.

- Wind gusts from 35 to 50 mph across the plains this afternoon
  with some blowing dust possible.

- Elevated fire conditions due to dry conditions and gusty winds
  from the I-25 Corridor across the plains this afternoon.

- Light snow showers in the northern mountains today with light
  accumulations.

- Mild through Friday, then cooler this weekend - with Sunday
  likely seeing temperatures several degrees below normal. Warmer
  again for much of next week.

&&

.UPDATE...
Issued at 722 AM MST Thu Nov 6 2025

A Red Flag Warning was issued for zones 238 and 239 which includes
the cities of Boulder and Fort Collins and surrounding areas.
Currently, wind gusts are around 50-60 mph in these zones with
relative humidity around 16-19%. With fuels being so dry and the
wind being so strong, we made the decision to go ahead and issue
the warning despite relative humidity not expected to reach the
15% threshold. Dew points should increase throughout the day and
winds will slightly weaken so the worst red flag conditions should
be in the morning. We are monitoring whether the warning should be
expanded eastward.

UPDATE Issued at 253 AM MST Thu Nov 6 2025

Winds have been strong early this morning in the higher mountains
with gusts from 60 to 70 mph in a few locations.  Cross-sections
show cross barrier flow from 50-55 kts today but the mtn wave
remains weak. There will be some subsidence moving across by midday
which will allow for winds to mix down into the foothills and across
the plains.

At this time, wind gusts should stay below high wind criteria in
most spots. However a few gusts to 75 mph may occur in the normal
wind spots in the foothills and higher mtns. At lower elevations,
wind gusts up to 60 mph may occur from Wellington to the WY border
along I-25. Meanwhile across the rest of the plains gusts will
range from 35 to 50 mph. In addition, may see some blowing dust
where the strongest winds occur as well.

In the mtns, there will be periods of snow showers due to favorable
orographics thru the aftn into the early evening hours.  Snow
accumulations will be on the light side with the best chc in the nrn
mtns north of the I-70 mtn corridor.

&&

.DISCUSSION /Through Wednesday/...
Issued at 210 PM MST Wed Nov 5 2025

One piece of the large upper level trough over the Pacific
Northwest will eject and race east across the Northern Rockies
through Thursday. Flow aloft will strengthen considerably, and
due to increasing pressure gradients and large scale subsidence
we expect gusty winds to spread across much of the forecast area
late Thursday morning and afternoon. Peak gusts of 30-35 mph can
be expected across most locations, but gusts 40-55+ mph are
expected across most of the Front Range Mountains, foothills, and
Wyoming border area. Those winds will start overnight already
in/near the foothills with a marginal wind/stability profile for
mountain wave enhancement. Fire weather conditions will become
elevated to near critical given the winds on Thursday, but there
is a little cooling and moisture advection (not much!) to keep
humidities above critical thresholds. Nonetheless, with humidity
down to 16-22% in most of the lower elevations we will see
conditions favorable for fire spread in the cured and dry fine
fuels/grasses.

Also, Thursday should feature at least scattered coverage of light
snow showers in the mountains as the cold advection combines with
just enough mid level moisture. The highest snow coverage will
along/north of Rabbit Ears Pass to Rocky Mountain National Park,
with an inch or two over the higher slopes. I-70 mountain
corridor should see no impacts with only scattered light showers
and little if any accumulation.

Friday will feature a weakening pressure gradient, with lighter
winds across most of the lower elevations. While temperatures will
be a little cooler, it will still be several degrees above normal.

Saturday will be a near repeat of Thursday, with another shortwave
moving across the Northern Rockies. This shortwave passes by Friday
night into early in the day Saturday, and it is a bit deeper with
a little more moisture. Thus, most mountain areas should be able
to see a light snow accumulation, probably down to the I-70 Summit
County Corridor. Meanwhile, mid level gradients will be slightly
stronger than Thursday, so look for strong, gusty winds over all
of the mountains and the northeast plains. However, there are
signs of some slight anticyclonic turning that could keep winds
along the Denver/Boulder areas down a little compared to Thursday.
Humidity levels should once again stay above critical thresholds,
but there will certainly be elevated fire weather conditions
due to strength of wind in most locations.

The trend for cooler temperatures for the weekend continues.
Deterministic forecasts are catching up to the latest colder
solutions, but still lagging slightly behind the latest data.
Therefore, wouldn`t be surprised if all areas stay in the 40s for
high temperatures Sunday.

That chilly spell will be short-lived as a high amplitude upper
level high is expected to dominate the weather early next week.
Thus, a quick rebound to well above normal temperatures is
expected through the middle of next week with dry weather
persisting. Per latest long range ensemble data, the chance of
the first measurable snow for Denver will have to wait until at
least the 15th or 16th, which would work Denver toward the Top 5
latest snowfalls on record.

&&

.AVIATION /18Z TAFS through 18Z Friday/...
Issued at 1156 AM MST Thu Nov 6 2025

Strong west-northwesterly winds will be persistent throughout the
day today. Gusts could reach 40 knots with sustained speeds
between 20-25 knots at all terminals. The winds will weaken and
turn more northwesterly between 23-00Z this evening and the gusts
will end around 01Z.

Tonight and Friday, there will be light winds and VFR conditions.
Winds at DEN and APA will likely be variable in direction for the
majority of the daylight hours.

&&

.FIRE WEATHER...
Issued at 253 AM MST Thu Nov 6 2025

Elevated fire conditions due to gusty winds and dry conditions
will occur this afternoon from the I-25 Corridor across the
plains.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning until 5 PM MST this afternoon for COZ238-239.

&&

$$

UPDATE...Danielson
DISCUSSION...20
AVIATION...Danielson
FIRE WEATHER...RPK

NWS BOU Office Area Forecast Discussion