National Weather Service Forecast Discussion

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514
FXUS65 KBOU 142332
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
432 PM MST Sun Dec 14 2025

.KEY MESSAGES...

- Unseasonably warm and dry through Tuesday, with generally light
  winds outside of the higher elevations.

- Remaining warm Wednesday with strong winds expected, leading to
  fire weather concerns for portions of the foothills and plains.

- Light to moderate snow expected Wednesday afternoon into
  Thursday for the mountains.

&&

.SHORT TERM /Through Monday/...
Issued at 213 PM MST Sun Dec 14 2025

Upper level ridging over Colorado flattens during the day Monday as
northwest flow aloft begins to increase. For tonight, west winds in
the higher foothills and Front Range Mountains increase, with gusts
to 40 mph possible. Elsewhere, we are looking at relatively light
winds. Temperatures in the mountain valleys and lower lying areas
across the plains will be cooler spots, with lows in the teens and
lower 20s. On Monday, it will be mild again with temperatures well
above normal. High across northeast Colorado will reach the upper
50s to mid 60s. Cross sections show some high level moisture, mainly
during the morning, with decreasing high clouds during the
afternoon. Expect for those typical breezy locations in the
foothills and mountains, light winds will prevail Monday.

&&

.LONG TERM /Monday night through Sunday/...
Issued at 213 PM MST Sun Dec 14 2025

The flow aloft will become more WNW on Tue with cross-sections
showing only some mid and higher level moisture embedded in the
flow. With downslope flow over the area, highs will remain well
above normal with a few record highs possible at lower
elevations.

On Wed, an upper level trough will move across the area late in the
aftn thru Wed night.  Cross-sections show increasing moisture in the
mtns by Wed evening with favorable orographic flow.  In addition, a
rather stg upper level jet will move into the area which may lead to
some heavier banded snowfall in some mtn areas.  In addition, it
will be very windy as well. At lower elevations, downslope low level
flow will remain in place thru the aftn, with dry conditions
along with another day of record highs possible around the Denver
area. Meanwhile, a bora type front will move across nern CO by
late aftn into the evening hours. As a result, may see strong
winds develop across portions of the foothills and plains as this
feature moves across.

For Thu into Thu night, the flow aloft will continue WNW with some
moisture embedded in the flow. May see orographic light snow
continue in the nrn mtns mainly Thu aftn and night. At lower
elevations it will be dry and windy with highs dropping back to
more seasonal levels.

Looking ahead to Fri, the flow aloft will become more westerly.
This will lead to dry conditions along with warmer temperatures as
downslope flow redevelops. By Sat, another fast moving system may
affect the area bringing a chc of snow to the mtns with another
round of wind at lower elevations.

&&

.AVIATION /00Z TAFS through 00Z Tuesday/...
Issued at 419 PM MST Sun Dec 14 2025

VFR conditions expected through the TAF period. Light and variable
winds will persist before transitioning to drainage at KDEN/KAPA.
KBJC will see light westerly winds for the overnight hours.

Main question for tomorrow will be if a cyclone redevelops in the
afternoon that would shift winds more to the northeast than
portrayed in the current TAF. Despite the uncertainty with wind
directions roughly between 21-1Z, winds are expected to be 10kts
or less by late morning through the afternoon.

&&

.FIRE WEATHER...
Issued at 1258 PM MST Sun Dec 14 2025

Elevated fire conditions will be possible in the northern foothills
and across the plains near the Wyoming-Nebraska border Tuesday
afternoon due to gusty winds and dry conditions.  Elevated to
critical fire conditions will develop on Wednesday across the
foothills and plains due to expected strong winds and continued dry
conditions.

&&

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

&&

$$

SHORT TERM...12
LONG TERM...RPK
AVIATION...9
FIRE WEATHER...RPK

NWS BOU Office Area Forecast Discussion