507
FXUS65 KBOU 051759
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1059 AM MST Thu Mar 5 2026

.KEY MESSAGES...

- Warm Thursday, with critical fire weather conditions across the
  Palmer Divide and Lincoln County in the afternoon.

- Moderate to locally heavy snow is expected to impact the
  mountains and foothills Thursday night through Friday.

- A few inches of snow increasingly likely for most of the lower
  elevations, favoring minor impacts. Continued uncertainty makes
  the forecast especially dynamic, and potential for locally
  moderate travel impacts does exist for portions of the I-25
  corridor from Denver southward to the Palmer Divide and portions
  of the northeast plains.

- Warmer and drier Saturday through Monday. Windier conditions
  develop as early as Tuesday

&&

.DISCUSSION /Through Wednesday/...
Issued at 1104 PM MST Wed Mar 4 2026

Will have one more mild day before a significant change occurs Thu
night through Friday.  SW flow aloft will be across the area on Thu
as sfc low pres extends from near Denver into sern CO.  This will
allow for gusty south winds across the Palmer Divide and east
central Plains.  Highs across the plains will be from 65 to 70
degrees.

For Thu night into Fri, an upper level trough will move from the
Great Basin into Colorado with a closed low over swrn CO by 12z Fri.
This low is fcst to move northeast and be over swrn NE by early Fri
evening.  Models show favorable QG ascent across the area on Fri
which moves northeast of the area Fri night. Low level winds will
become northeast Thu night and then more northerly by 12Z Fri.
Snow will gradually increase in the mtns late Thu night and then
spread across the plains on Fri. Snow will continue into Fri
evening and then decrease by midnight in most areas.

As far as snow amounts, mtn areas along and east of the divide
should receive heavy snow.  In addition, there is some potential for
heavier snow across the srn foothills where N to NNE low level flow
is enhanced. Currently have an advisory out but this may need to be
upgraded to a warning if the trend for heavier snow continues in
later model runs.  Furthermore, may need an advisory across the
Palmer Divide as this area will do well with northerly low level
flow.  Across the plains, if low level flow does become more
northerly by 12z Fri then snow amounts along nrn areas of the I-25
Corridor and across the plains closer to the WY-NE would be only an
inch or so. In the Denver Metro area, amounts from 2 to 4 inches
will be possible. If the upper level low is more organized than
expected, this could lead to a band of heavier snow just to the N
and NW of its track across portions of the plains from east of
Denver towards the Akron area.

By late Fri night into Sat the upper level trough will move
northeast of the area with drier air moving in. As a result, will
see dry conditions on Sat with temps near seasonal levels. On
Sun, dry NW flow aloft will be over the area as a sfc lee trough
develops. This will allow for downslope low level flow, with
warmer temperatures, as highs rise into the 60`s across the
plains.

Looking ahead to Mon and Tue, the flow aloft will be mainly westerly
with cross-sections showing only some mid and higher level moisture
embedded in the flow.  Thus should see above normal temperatures
with mainly dry conditions both days.

&&

.AVIATION /18Z TAFS through 18Z Friday/...
Issued at 1059 AM MST Thu Mar 5 2026

Southerly winds will increase this afternoon with gusty south winds
at APA. This is expected to produce a Denver cyclone. The stronger
south winds are not expected to reach DEN, with southeast winds
slowly backing to northeast 20-23Z. Though, a fair amount
uncertainty remains with the wind forecast since the cyclone hasn`t
formed yet. A strong cold front will bring north winds 03-05Z with
gusts to 40 knots as the front pushes through. North winds then
continue overnight and through Friday.

Clouds will lower behind the front, dropping to 4000 to 7000 feet
05-07Z. Ceilings continue to fall overnight reaching 500 to 2000
feet around 09-12Z on Friday. Snow moves in a couple hours later,
11-14Z. This snow could be intense at times, 12-18Z, with
visibility down to a half mile for a short time and ceilings at
or below 500 feet at all terminals. Snow will decrease in
intensity after 18-20Z and ceilings and visibility will increase
as a result.

&&

.FIRE WEATHER...
Issued at 1104 PM MST Wed Mar 4 2026

South to southwest winds will increase on Thursday in advance of
the incoming storm system. Downslope flow off the Palmer Divide
will result in warm and dry conditions, with humidity falling into
the 10-15% range. Mixing heights should be quite elevated, and
help promote efficient mixing of winds aloft down to the surface.
The stronger flow aloft, however, likely won`t arrive until later
in the afternoon, thereby shortening the window of critical
conditions slightly (mainly mid and late afternoon), when gusts
25-30 mph will be most likely. Tuesday`s wetting rains were rather
localized and not widespread across the warned zones, so fuels
were deemed susceptible.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory from midnight tonight to midnight MST
Friday night for COZ030-032-035>037.

Winter Weather Advisory from midnight tonight to 8 PM MST Friday
for COZ031.

Winter Storm Warning from midnight tonight to midnight MST
Friday night for COZ033-034.

Red Flag Warning until 6 PM MST this evening for COZ241-246-247.

Winter Weather Advisory from 6 AM Friday to midnight MST Friday
night for COZ041.

&&

$$

DISCUSSION...RPK
AVIATION...12/AA
FIRE WEATHER...RPK

NWS BOU Office Area Forecast Discussion