372
FXUS65 KBOU 120005
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
605 PM MDT Fri Sep 11 2026

.KEY MESSAGES...

- Very warm today with only isolated high based showers/virga
  late this afternoon and evening.

- Slight increase in shower/storm coverage this weekend. Cooler
  Saturday, then warmer Sunday.

- Unsettled pattern next week, with multiple cold fronts expected
  to bring a few more noticeable cooldowns.

&&

.DISCUSSION /Through Friday/...
Issued at 1245 PM MDT Fri Sep 11 2026

This morning`s wave cloud kept some heat relief in place for the
northern corridor for the first half of the day. Now that the
cloud has dissipated, temperatures are quickly heating, with KLMO
seeing an eight degree warming in the past hour alone.
Temperatures were adjusted slightly to account for the cooler
morning, but we are still expecting a hot day across the lower
elevations due to downsloping winds and a slight warming in
temperatures aloft. Water vapor imagery shows moisture has
slightly increased in the westerly flow aloft through the morning.
We still expect some isolated high-based showers to develop this
afternoon over the higher elevations, with some virga showers
expected to bring gusty outflows to the lower elevations. We may
manage to squeeze a few sprinkles out of some of them, but mostly
just expect 30-40 mph winds as virga passes over for areas east of
the mountains.

A cold front is expected late tonight/early Saturday morning that
will bring some gusty northerly winds across the plains and
cooler temperatures for Saturday. A slight increase in moisture
is expected with the front as well. Afternoon showers and a few
storms will be possible, with the best chances being over the
northern mountains where instability will be greatest, but can`t
rule out some holding together long enough to push off the higher
elevations. Have added a mention of at least slight chance for
PoPs to the forecast across the northern plains and areas along
the Palmer Divide.

Sunday is still on track to be the hottest day of the week in
between cold fronts. While the NBM seems to have a warm bias, most
guidance does show afternoon highs in the low to mid 90s, so
afternoon highs were trimmed back slightly to be more in line with
the majority of guidance. Either way, it will still be hot for the
second week of September. There will be some better instability
in place across the northeast plains that if tapped into, could
allow for some stronger to severe storms in the afternoon/evening.

Not much has changed in the long term forecast today, with the
northern tier still expected to remain active over the next week.
A few cold fronts are still progged to bring a few more cooldowns
through the week, and afternoon showers and storms will be
possible each afternoon.

&&

.AVIATION /00Z TAFS through 00Z Sunday/...
Issued at 603 PM MDT Fri Sep 11 2026

VFR expected through the TAF period. Current radar imagery shows a
push of WNW winds moving through the Denver metro as well as a few
microbursts in the vicinity of KDEN. Virga showers and gusty
outflows will continue to be possible through 02Z this evening.
Winds will become southerly later tonight before a cold front tracks
through the terminals between 09Z and 11Z, bringing a N-NE wind
shift.

Another round of virga showers will be possible tomorrow afternoon,
likely starting at ~22Z. Although conditions look slightly less
favorable than today, a few microbursts with gusty winds up to
30KT cannot be ruled out, particularly near KAPA and KBJC. We
have kept a PROB30 out of the TAF for KDEN at this time given low
confidence in convection being able to survive off of the
foothills and Palmer Divide, but it may need to be added if
future guidance suggests otherwise.

&&

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

&&

$$

DISCUSSION...9
AVIATION...AA

NWS BOU Office Area Forecast Discussion