830
FXUS65 KBOU 140929
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
329 AM MDT Sat Mar 14 2026

.KEY MESSAGES...

- Warm, dry, and windy conditions will sustain widespread critical
  fire weather conditions for the lower elevations today, with
  elevated concerns in our high mountain valleys. Gusts 40-60 mph
  are expected, strongest near the base of the foothills where
  winds may briefly gust up to 70 mph between 2 pm and 5 pm.

- A cold front tonight will bring sub-freezing temperatures with
  strong north winds and light snow to the lower elevations into
  Sunday. Wind gusts from 55 to 65 mph may accompany the frontal
  passage late this evening and overnight across the plains.

- In the mountains, a period of heavy snow and whiteout conditions
  tonight will produce dangerous conditions on the passes into
  early Sunday.

- Rapid warming begins Monday into Tuesday, potentially
  culminating in record-breaking temperatures mid to late next
  week.

&&

.UPDATE...
Issued at 309 AM MDT Sat Mar 14 2026

After analyzing cross-sections from a few higher res models, it
does appear there will be a brief mtn wave this aftn which may
enhance winds in and near the foothills for a few hours. Overall,
it appears areas from Boulder county into nrn portions of
Jefferson county would have the highest potential for gusts up to
70 mph, with a few localized higher gusts. Best window for these
stronger winds looks to be from 1 pm to 5 pm.  If winds end up
being a bit stronger than anticipated and more widespread, may
need a short fuse high wind warning for a few hours this aftn.

Meanwhile, for tonight, a strong cold front will blast its way
across the plains late this evening and overnight.  It appears
there will be an initial wave of strong winds behind the front
with gusts from 55 to 65 mph certainly possibly for a few hours.
As a result, have moved up the high watch to late this evening.
Also have added areas along and east of the I-25 Corridor around
the Denver area along with central and southern areas of Weld
county.

&&

.DISCUSSION /Through Friday/...
Issued at 1124 PM MDT Fri Mar 13 2026

Calm before the storm currently. It`s a mild night across northeast
Colorado with modest downslope flow in place and breezy conditions
confined to the higher elevations. Fortunately, and unlike last
night, smoke won`t be a concern this morning for most areas given
continued light west winds through the night, save perhaps for the
far northeast corner (Sedgwick/Logan Counties) for a brief period
before sunrise.

For once, we`ve seen good model consistency over several days with
respect to conditions leading up to and following our approaching
cold front. Today, strengthening zonal flow along the base of an
amplifying upper-level trough will begin to rapidly mix down mid to
late morning as surface temperatures warm into the mid to upper 70`s
across the urban corridor and plains respectively. By this
afternoon, sustained speeds 25-30 mph and gusts 35-50 mph will
become widespread, driving critical fire weather conditions for the
lower elevations, and locally producing blowing dust. Cross-sections
and forecast sounding continue to suggest lacking ingredients for a
true mountain wave event (no stable or mean state critical layers,
nor shear reversal aloft). The latest 00z HRRR, which was an outlier
earlier in advertizing significantly stronger gusts up to 80 mph,
has tapered that peak wind potential for closer alignment with other
high-resolution guidance, which is in no way surprising. Would be
skeptical of any such outliers going forward barring a significant
change in the underlying ingredients. That being said, confidence is
high in a short 2-4 hour window of stronger gusts ~55-65 mph
spreading off the foothills and into adjacent urban corridor
locations (particularly west of I-25) between 2-6pm MDT, coincident
with the peak in pressure gradients and arrival of stronger mid-
level flow as the trough approaches.

The strong cold front is slated to cross into Colorado near 9pm this
evening, plus/minus an hour, and zoom south through the remainder of
the evening. It`ll bring an initial surge of north winds that will
pack a punch, with gusts 45-60 possible for the lower elevations,
with only modest buffering thereafter. A sharp drop in temperatures
should allow for a quick transition of any rain/wintry mix to snow,
as a band or two sweep through the lower elevations (lasting no more
than 1-2 hours). A quick dusting to 1" can be expected for most of
the urban corridor from about midnight through 4-5AM, with 1-3"
favored for the Palmer Divide where the upslope component will be
maximized. In the high country, snow will develop quickly this
evening for the Park and Medicine Bow Ranges, spreading south with
the front overnight. Snowfall rates are likely to exceed 2-3"/hr at
the peak, coincident with strong winds that will exceed 70-80 mph
near and above timberline prior to sunrise, producing extremely
treacherous conditions and whiteout conditions at times near
mountain passes. Snow will taper off quickly Sunday morning for all
areas, but blowing snow will remain a concern in the high country. A
few snow showers may linger through Sunday evening, even for the
lower elevations, but additional accumulations should be limited
past ~8am. Returning to the plains, steady north winds will
produce gusts up to 60 mph through Sunday afternoon, and the windy
conditions will result in wind chills barely climbing above 20F
during the day (if at all). Additionally, for any areas that
receive little to no snow tonight, moderately dry conditions will
develop by Sunday afternoon and could support elevated to near-
critical fire weather conditions for much of the plains, as well
as patchy blowing dust once more.

To the wind, we can finally say adios, arrivederci, good riddance
come Monday as the trough ejects into the Midwest. While the
Upper Midwest is "treated" to a likely March blizzard, Colorado
will turn its eyes to the expanding ridge emerging over the West
Coast, leading to a rapid warming trend early to mid week and the
return of lighter winds and dry conditions. The ridge is set to
become rather imposing beginning Thursday and continuing into the
weekend, with 500mb heights progged to peak between 588-594dam
near Arizona per ensemble means. Though some weakening is
suggested thereafter, the ridge axis is favored to displace east
over Colorado Friday through Sunday - likely our hottest days of
the week. The potential to reach or exceed all-time March highs
(mid/upper 80`s) appears well within reach assuming no significant
trends with the ridge`s strength or placement.

&&

.AVIATION /00Z TAFS through 00Z Sunday/...
Issued at 540 PM MDT Fri Mar 13 2026

Will keep some decent westerlies going into the early evening hours
at DIA. Model consensus is showing drainage to start at 06Z or 07Z
tonight. Strong westerlies are progged to kick in again on
Saturday by 18Z-19Z. There will be no ceiling issues.

I left the arrival of the strong cold front with northerly winds
behind that it that as it is expected to move into DIA around
06Z-07Z.

&&

.FIRE WEATHER...
Issued at 330 AM MDT Sat Mar 14 2026

Widespread critical fire weather conditions, and locally extremely
critical, will develop today across all of the lower elevations
as strong west winds mix down to the surface, with winds
strengthening beginning mid/late morning. Sustained speeds will
largely range between 25-30 mph (slightly lower for the eastern
plains, slightly higher at times west of I-25), with gusts 30-50
mph most of the afternoon. This will coincide will humidity values
of 7-14%, and temperatures that will rise into the mid to upper
70`s. Although no headlines are in effect for our foothills per
indications on fuel susceptibility from our land management
partners, there will be localized areas of near-critical to
critical conditions namely for the lower elevations and any
drier and snow-free aspects. Although a pronounced mountain wave
is not expected, a window of stronger westerly gusts 55-70 mph is
expected to push off the foothills into adjacent lower elevations
starting between 1 and 2 pm MDT, and lasting through 5-6pm MDT,
most pronounced for eastern Boulder County into northeastern
Jefferson county.

A sharp cold front will bring a shift to north winds between 9pm
and midnight from north to south. Wind speeds will remain strong
with the front with potential for localized gusts 50-60 mph,
although a significant moderation in humidity as well as some snow
showers are expected behind the front.

Fire danger on Sunday for the lower elevations will be entirely
dependent on any snow that occurs tonight. Accumulations are
expected to be light (mostly under 1", less for much of the
plains, and slightly more for the Palmer Divide). For any areas
that receive little/no snow, continued strong north winds Sunday
with gusts up to 60 mph in the plains could sustain elevated to
near-critical conditions as humidity potentially lowers below
25-30% in the afternoon.

Lighter winds are expected Monday onwards, albeit with a rapid
warming and drying trend which will continue through the weekend.
Heightened fire concerns may return at some point towards the end
of the week, depending on trends in forecasted winds.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory from 6 PM this evening to 9 AM MDT
Sunday for COZ031-033-034.

Red Flag Warning from 11 AM this morning to 9 PM MDT this
evening for COZ238>251.

High Wind Watch from this evening through Sunday afternoon for
COZ040>051.

&&

$$

UPDATE...RPK
DISCUSSION...BRQ
AVIATION...RPK
FIRE WEATHER...RPK/BRQ

NWS BOU Office Area Forecast Discussion