National Weather Service Forecast Discussion

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645
FXUS65 KBOU 102345
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
445 PM MST Sat Jan 10 2026

.KEY MESSAGES...

- Dry with a warming trend Sunday through Tuesday.

- Slight (< 20%) chance of rain or snow across northeast Colorado
  early Wednesday.

- Elevated fire weather conditions possible (50%) across the
  plains on Thursday and a hints of a cool down by next weekend
  with 10-20% chance of snow for the mountains.

&&

.DISCUSSION /Through Saturday/...
Issued at 130 PM MST Sat Jan 10 2026

Tonight, northwest flow aloft continues with a deep trough over the
Great Lakes.  It will remain dry with just a few high clouds.  Low
temps will be seasonably cold but there may be enough wind across
the plains to keep temperatures from dropping much below 20. The
exception will be across the snowpack from the Palmer Divide east
across Lincoln County, where we dropped low temps several degrees
below guidance.

Sunday will be dry with a building ridge to the west.  700 mb temps
should warm to around -1 degC, supporting highs across the plains
in the 50s, but cooler across the areas with snowpack across the
Palmer Divide and Lincoln County. Highs in the mountain valleys
should be in the upper 30s to around 40.

Monday and Tuesday will be heavily influenced by the ridge across
the Great Basin.  It will remain dry at least through Tuesday
evening.  A slight warming trend is expected with 700 mb temps
warming to around +3 degC Monday and Tuesday.  Highs across the
plains and I-25 corridor should be in the mid 50s to around 60, and
the 40s for the mountain valleys.  Breezy conditions are likely
Tuesday afternoon along the WY border out to the northeast
corner, but nothing more than gusts to 25 mph at this time.

Late Tuesday into Wednesday all models/ensembles agree an impressive
jet streak will dig straight south across the Central U.S. Plains on
the backside of yet another deep/strong Great Lakes trough.  It will
also advect some mid-level moisture into far northeast Colorado. The
right exit region of the jet gets really close to the northeast
corner of Colorado, and this is the subsident side of the jet
streak.  Given the strength of the cross jet gradient, we expect
pretty strong subsidence. Nevertheless, global ensembles continue to
want to hold onto PoPs up to 20%.  If any precipitation makes it to
the ground early Wednesday across the northeast corner, that would
be impressive.  Elsewhere, with strong NNW flow at ridgetop, and
very little moisture embedded in the flow, it`s not likely to snow
in the mountains (though very light snow is possible) or the I-25
corridor. There should be a dry cold front moving across the area on
Wednesday which will knock temps back to near normal, with highs in
the 40s across the plains (mid 30s under cloud cover and colder air
aloft across the northeast corner), and 20s to low 30s in the
mountain valleys.

Thursday temperatures will moderate with dry northwest flow aloft
as the exceptionally strong trough across the Ohio valley
continues to move east. Expect temperatures back into the
mid/upper 50s across the plains and 40s in the mountain valleys.
It will be breezy across the plains though given the strong
pressure gradient across the Midwest US, with northwest wind gusts
exceeding 30 mph. Elevated fire weather conditions are certainly
possible Thursday afternoon across much of the plains.

Friday and beyond, model agreement is quite low despite a
continuation of northwest flow.  So much depends on the evolution of
a third, deep, cold trough moving across the northern U.S. later
next week. Euro ensemble and GEFS are bleak for any precipitation
but several members of the GEFS and Euro ensembles have some
mountain snow for Friday along and behind a cold front. The really
cold air is more than likely to be east of our area with a
glancing blow across the northeast corner. However, even across
the I-25 corridor the Euro ensemble mean high for Friday is 40
with a spread of 50-22 deg. GEFS is pretty much identical to the
Euro for temps across the I-25 corridor on Friday. Unfortunately
for those of us looking for snow across the I-25 corridor or
eastern plains, about 1/3 of GEFS have light snow, and 1/5 of the
Euro members have light snow sometime on Friday. Pretty bleak.
Across the mountains late Friday into Saturday the ensemble output
of only marginally higher than for the I-25 corridor, with about
half of the members generating light snow from GEFS and the Euro.

&&

.AVIATION /00Z TAFS through 00Z Monday/...
Issued at 425 PM MST Sat Jan 10 2026

Overall, a pretty quite TAF package. VFR conditions are expected
through Sunday. Winds will generally stay from SW this evening,
gradually turning more southerly overnight. By late tomorrow
morning, winds will be SSE. Winds speeds should generally stay
below 13kts through this TAF package, but we could see an
occasional gust from the west up to 20kts at KBJC through the
evening.

&&

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

&&

$$

DISCUSSION...Schlatter
AVIATION...AP

NWS BOU Office Area Forecast Discussion