National Weather Service Forecast Discussion

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348
FXUS65 KBOU 021127
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
527 AM MDT Thu Apr 2 2026

.KEY MESSAGES...

- Areas of fog northern Denver suburbs to portions of the
  northeast plains early this morning.

- Quick but brief warm up today, with breezy southwest winds and
  locally critical fire weather conditions developing in the
  afternoon.

- Turning blustery and colder tonight through Friday. Another
  round of snow in the mountains, this one with more impacts due
  to colder temperatures. Plains still look mostly dry with only
  isolated light showers possible.

- Dry with a gradual warming trend this weekend through early next
  week.

&&

.DISCUSSION /Through Wednesday/...
Issued at 1155 PM MDT Wed Apr 1 2026

One system is moving out with showers ending and clearing skies
across the plains. The exception is some fog developing over the
northern sections of Denver which should spread/migrate slowly
northward into the early morning hours Thursday as light southerly
drainage winds spread down the South Platte River Valley. That fog
will burn off by mid morning, allowing more sunshine and warming
temperatures. Highs will quickly rebound from the cooler readings
of the last couple days as sunshine, downslope, and warm
advection under a flat ridge all join forces. It will become
breezy in most areas, but likely not until afternoon, and
potentially not until very late afternoon or early evening in a
few spots north of Denver which will hold inversions the longest.
Highs should still be able to reach the lower 70s over most of the
plains. See Fire Weather Section for more info regarding winds
and humidity and locally critical fire weather conditions.

For tonight and Friday, the next upper level disturbance will
move into the region. This is a more compact and colder upper low
than the last, but the track will be too far north (through
Wyoming) to bring us much chance of precipitation east of the
mountains as significant downslope develops. The mountain areas,
however, will see a quick blast of healthy snow starting this
evening but diminishing about as fast overnight as more stable air
arrives along with drying aloft. Thus, snow totals will be
marginal for any highlights, but we do expect some travel impacts
as temperatures will be considerably colder with this storm
system. Some impacts may linger into Friday as models suggest a
bit of wrap around moisture impacting the mountains mainly north
of I-70, but additional accumulations should be light as moisture
looks relatively limited. A strong cold front will blast across
the plains this evening with a period of gusty winds and colder
temperatures. It`s not impossible we see a brief light shower
behind the front given the jet location and frontogenesis, but
overall moisture looks meager and downslope dominates. By Friday,
the flow turns more west/northwest and strong subsidence develops
as shown in quite impressive QG fields. 700 mb winds increase to
35-40 kts and given the subsidence we will see healthy mixing and
momentum transfer. Thus, most plains locations including the I-25
Corridor should see 40-45 mph wind gusts through the day. However,
with the impressive subsidence would not be surprised to see
stronger gusts especially in the wind prone areas near the
foothills and near the Wyoming border where gusts to 55 mph seem
reasonable - close to High Wind Criteria. We`ll continue to
monitor with later updates.

After that system, our weather settles down as the flow aloft
gradually relaxes. With flat ridging, we expect gradual warming
through early next week. There is good ensemble agreement with
temperatures through Sunday, and then some uncertainty Monday -
Wednesday with potential for backdoor cold fronts sloshing across
the plains. That said, the overall trend will be for warmer and
mostly dry weather. We`re eyeing another potential storm system
for late next week...we`ll need to keep em coming to aid our
current drought situation.

&&

.AVIATION /12Z TAFS through 12Z Friday/...
Issued at 527 AM MDT Thu Apr 2 2026

Fog has developed across the northern part of the Denver area,
including DEN and BJC. Southerly winds just south of DEN will
spread northward bringingdrier air that will cause the fog to
dissipate 1130-1230Z. At BJC, fog may linger a little longer,
through about 13Z. After this, VFR will prevail through tonight
at the Denver airports. South to southwest winds will continue
this morning and early afternoon. Between 20-22Z winds will turn
west-southwest and increase with gusts up to 25 knots. Southwest
winds will then decrease after 00-01Z, but a cold front will bring
a wind shift to the north/northwest and increase winds between
04-06Z.

&&

.FIRE WEATHER...
Issued at 1155 PM MDT Wed Apr 1 2026

Thursday will see critical wind gusts to 30-35 mph and humidity
down to near 15% over the Palmer Divide area into east central
Colorado. However, we did have about a tenth of an inch of rain
from Elbert County through northern Lincoln County so that should
help today`s fire concerns a little. Thus, we`ve opted to upgrade
only southern Lincoln County where little if any precipitation
occurred.

For Friday, strong and gusty west-northwest winds can be expected.
Humidity readings will be reaching near critical thresholds
despite the cooler temperatures. We may issue Fire Weather Watches
as humidity values drop to 15-20% (above criteria), but winds
will be stronger and gust to 40-45 mph in many locations of the
plains and I-25 Corridor.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning from noon today to 8 PM MDT this evening for
COZ247.

&&

$$

DISCUSSION...20
AVIATION...12
FIRE WEATHER...20

NWS BOU Office Area Forecast Discussion