National Weather Service Forecast Discussion

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338
FXUS65 KBOU 272038
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
238 PM MDT Sat Jun 27 2026

.KEY MESSAGES...

- Widespread and prolonged critical fire weather conditions will
  be present in the high country through the weekend as warm, dry
  and windy conditions develop, continuing at times into early
  next week.

- Warmer today with an isolated severe thunderstorm possible over
  the far northeast plains this afternoon into the early evening
  hours.

- Little change in the forecast pattern through the middle part
  of next week. The only exception will be for a slight chance of
  thunderstorms over the plains on Tuesday.

&&

.DISCUSSION /Through Saturday/...
Issued at 132 PM MDT Sat Jun 27 2026

As expected, it`s warm, dry, and breezy across much of the
forecast area. Temperatures in the Denver metro have warmed into
the upper 80s to mid 90s (including a 94F so far at DEN), with
similar temps across the plains. Surface analysis shows a dryline
focused from roughly Peetz down into Yuma county in far
northeastern Colorado. East of the dryline resides a fairly
impressive convective environment, with MLCAPE approaching 2000
J/kg while effective layer shear remains around 35-45kt. Most
guidance makes an attempt or two at convective initiation along
the dryline where surface convergence is maximized. Current day
cloud phase satellite shows a small cumulus field slowly starting
to grow across Logan county. It`s a rather conditional setup, but
a supercell or two could try to develop this afternoon/evening
with hail/wind as the primary threats with relatively small,
straight-line hodographs.

Meanwhile, fire weather continues to be a concern across the high
country. Critical fire weather conditions have developed across
the high mountain valleys with gusts reaching 50 mph at Kremmling
and a couple RAWS sites. Critical fire weather conditions will be
the theme of the next several days across the high country, as dry
southwesterly flow remains in place. More on Fire Wx in the
section later in this AFD.

The main synoptic players for the next week won`t really move
much, with a broad upper trough over the northwestern CONUS and
large ridge across the Ohio Valley. It`s no surprise that
tomorrow`s weather will be largely the same as today, with highs
in the low to mid 90s and gusty winds through the day. One
shortwave should get close enough to the forecast area to push a
weak cold front through on Sunday night, leading to slightly
cooler temperatures for Monday. The flow aloft is expected to
gradually weaken through the period, with a couple attempts to get
some moisture into the region by mid/late week.

&&

.AVIATION /18Z TAFS through 18Z Sunday/...
Issued at 1220 PM MDT Sat Jun 27 2026

Winds are already gusting to 25-30KT from the SW-SSW at KDEN and
KAPA. Gusty southwest winds are expected to continue through the
afternoon, with gusts weakening by ~02Z. Winds at KBJC have been a
bit tricky due to airflow-terrain interactions, and the direction
has had more of a southeasterly component. Steady southerly drainage
winds are expected to be in place at the three airports overnight.
Another breezy day with gusts up to 25KT appears to be in store for
tomorrow, although the prevailing wind direction will be more
southerly than today`s. One point of uncertainty for tomorrow`s wind
forecast is the potential for a cyclone developing north of the
Denver metro area mid-afternoon. If a cyclone were to develop, winds
at KBJC would take on a northwesterly component although KDEN and
KAPA would likely remain S-SW.

Near-surface smoke concentrations from the wildfires in Utah remain
low through the TAF period. However, model guidance suggests some
light smoke aloft making its way to the Denver area between
00Z-03Z today which could briefly impact slantwise visibility as
the sun begins to set.

&&

.FIRE WEATHER...
Issued at 132 PM MDT Sat Jun 27 2026

Critical fire weather conditions will persist across the high
country for the next several hours. Gusty winds have developed as
expected, with nearly every station within the Red Flag Warning
area seeing gusts of 35-50 mph. Relative humidity is generally
between 10-16% across most of the area and little change is
expected this afternoon. Winds will be slow to recover tonight and
humidity will also be slow to recover overnight into Sunday
morning.

While an upper trough slowly approaches the region, there will be
little change overall in fire weather conditions Sunday.
Southwesterly winds will develop during the morning hours, with
deep mixing leading to RH falling again to around 10-17%. While a
cold front is expected to bring some relief Sunday night
(particularly with respect to humidity recovery), no precipitation
or substantial cooling is expected during the week. Additional
elevated to critical fire weather conditions are expected each day
next week, with additional Fire Weather Watches likely needed for
at least Monday. Fuels status may also need to be re-evaluated for
areas that did not see significant precipitation over the last
week or so.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning until midnight MDT tonight for COZ211>214-
216>218.

Red Flag Warning from 11 AM to 9 PM MDT Sunday for COZ211>214-
216-218.

&&

$$

DISCUSSION...Hiris
AVIATION...AA
FIRE WEATHER...Hiris

NWS BOU Office Area Forecast Discussion