589
FXUS65 KBOU 111957
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
157 PM MDT Sun Oct 11 2026

.KEY MESSAGES...

- Unseasonably warm and mostly dry for Sunday and Monday.

- Isolated to scatteredshowers (15-35% coverage) and a couple
  weak storms over themountains possible again this afternoon.
  Some showers possible through Monday morning for the northern
  high country.

- Pattern change arrives this week, with cooler temperatures
  finallyarriving by Tuesday.

- Main precipitation chances from late Tuesday through Wednesday,
  possibly continuing on Thursday. A few inches of mountain snow
  becoming increasingly likely, mainly above 10,000 feet.

&&

.DISCUSSION /Through Sunday/...
Issued at 150 PM MDT Sun Oct 11 2026

It will be another day in the 80s for the plains. Even with a few
more clouds today compared to previous days, temperatures are
forecast to be only a degree or two cooler with highs in the low to
mid 80s. A rather strong jet overhead will continue to strengthen
and bring breezy conditions to much of the area today. The high
country overnight could even see some gusts of 40-50 mph at the
highest elevations towards sunrise Monday. The moisture associated
with former Tropical Storm Rachel remains well off to our west.
Isolated to scattered showers are possible for the high country
today with the potential for these to continue into the overnight.
The northern high country (i.e. Jackson County) looks to be most
favored. Rainfall amounts look light with 0.2" at most and slightly
higher totals possible for the Park Range. There is a low risk for
some marginally severe wind gusts (~50-60 mph) associated with these
storms given the strong SW flow aloft.

Monday morning could be the fifth day in a row and 7 out of the last
8 days with record warm minimums for Denver (assuming this morning`s
low temperature holds through the end of the day). The current
forecast is 56 F which would break the record of 55 F set in 1996.
Expect more of the same for Monday with high temperatures only
dropping a few degrees into the upper 70s and low 80s for the plains
even with less clouds than today as the mid-levels cool a touch.
There could be a brief period of elevated fire weather conditions on
the far eastern plains Monday afternoon. Low rain chances will again
be possible for the northern high country, though coverage looks
isolated. PoPs increase on late Monday for the northern high country
and slowly spread eastward on Tuesday as the long-awaited upper
level low moves closer to our area.

Some changes to this rather stagnant pattern finally start on
Tuesday as a cold front pushes through late Monday into early
Tuesday. This will drop high temperatures on Tuesday into the 60s or
possibly even the upper 50s on the plains (except for our far
southeastern counties)- finally near average for this time of year.
The cold front is trending stronger than in previous forecasts.

Forecast models have started to converge on showing the upper level
low moving through Utah, western CO, and into our area by late
Wednesday. As a result, PoPs should remain at or above 50% across
much of the area for Wednesday. Increased cloud cover and rain will
mean that high temperatures on Wednesday for the plains will
struggle to make it out of the 50s with the high country stuck in
the 30s and 40s. Model guidance is trending even lower with high
temperatures for Tuesday and Wednesday with this latest forecast
package reflecting that change. This will likely be the coolest day
of the season so far! Some precipitation could linger for the area
on Thursday, but rain chances remain rather unclear as the
synoptic pattern becomes murky. The location of the deepest
moisture associated with the remnants of Hurricane Simon towards
the end of the week also complicates the forecast.

All ensemble members continue to show measurable precipitation
for the urban corridor with the average still around 0.5" or
slightly higher. There will of course be some variations once the
finer-scale details can be worked out over the next few days. The
northern mountains could have QPF closer to an inch or more given
the longer duration of precipitation there. The 12z ECMWF
ensemble guidance has trended up with QPF amounts for the urban
corridor and is now more in line with the GFS ensemble members,
which have been rather consistent over past few days. The
mountains and high country (mainly above 10,000 feet) are still on
track to receive a few inches of snow with the northern mountains
continuing to look the most favorable- perhaps reaching advisory-
level criteria. Ensemble guidance shows Friday continuing to stay
below average with warming temperatures- to a few
degrees above average for this time of year- for the weekend.

&&

.AVIATION /18Z TAFS through 18Z Monday/...
Issued at 1120 AM MDT Sun Oct 11 2026

VFR conditions will prevail for all terminals through the TAF
period. Breezy S/SSW winds are present south of I-70 at this hour
and will gradually migrate north over the coming 1-2 hrs,
impacting KDEN with gusts of 20-25 kts. Wind direction and speeds
are expected to hold mostly steady through early evening,
weakening some after 02-03Z. Nonetheless, robust drainage winds
of 10-15 kts are likely to continue overnight for KDEN and KAPA.
For Mon AM, wind direction is highly uncertain at KDEN
specifically. For now, bulk of guidance keep breezier S/SW flow
just far enough to the south to allow for a few hours of lighter
(< 10 kt) W/SW winds late morning into early afternoon. There`s
distinct potential however for incursions of stronger southerly
winds, as well as a shift to more southeasterly flow later in the
afternoon.

&&

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

&&

$$

DISCUSSION...MV
AVIATION...BRQ

NWS BOU Office Area Forecast Discussion