National Weather Service Forecast Discussion

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526
FXUS65 KBOU 051750
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1050 AM MST Wed Nov 5 2025

.KEY MESSAGES...

- Generally dry conditions through the next several days.

- Gusty winds and elevated fire conditions are expected on
  Thursday and Saturday across the plains.

- Weak systems will bring very light snow to the northern
  mountains Thursday and Saturday.

&&

.DISCUSSION /Through Tuesday/...
Issued at 245 PM MST Tue Nov 4 2025

Another day of record or near-record highs occurred today with
many areas across the plains hitting the upper 70s and
temperatures hitting the mid 60s in the mountain valleys. A weak
cold front is currently in northeast Wyoming and across South
Dakota that will move across our forecast area late tonight. This
will turn winds to the northeast in the morning hours across the
plains and will keep temperatures 5-10 F cooler on Wednesday. A
DCVZ will setup on the east side of Denver metro with highs around
70 on the east side and highs in the mid 60s on the west side.

There are two main things to discuss in the long term besides the
generally mild and dry conditions. Those are multiple days of
elevated fire weather conditions and two very light snow events
for the northern mountains.

As for fire weather, Thursday will be mild, dry, and breezy
over the northern-most counties across the plains. This will lead
to elevated to near critical fire weather conditions from Greeley
to Holyoke and north to the WY and NE borders. On Saturday, wind
gusts up to 35 mph will spread across all of the eastern plains.
Temperatures will be closer to normal so relative humidity will
drop to around 20% which will result in elevated fire weather
conditions. The other days during the long term period will see winds
and humidity that will be lower than Red Flag criteria.

As for winter weather, a trough on Thursday and another early
Saturday morning will bring just enough moisture and orographic
forcing to the northern mountains of Colorado to produce snow. The
Park Range will see the highest snowfall amounts but only a
couple of inches will fall.

Ensemble guidance doesn`t show a decent signal for precipitation
across our forecast area until November 14-16th. Even then, it is
highly uncertain the plains will receive precipitation during
this period. Otherwise, temperatures will be 10-15 F above normal
with a chance for record highs especially Monday and Tuesday of
next week.

&&

.AVIATION /18Z TAFS through 18Z Thursday/...
Issued at 1050 AM MST Wed Nov 5 2025

East/southeast winds have developed at KDEN, and are expected to
gradually transition to a slightly stronger south/southeast
component through 20Z. However, that`s not entirely certain as
there`s a convergence/shear zone developing just to the west. So,
there`s a 30-40% chance winds could become light and variable
18Z-23Z. The overall flow isn`t terribly favorable for a true
Denver Cyclone (since it`s more southerly vs southeasterly), but
still expect that shear zone to become more defined and sink
slowly east/southeast 22Z-00Z and likely (60-70% chance) straddle
KDEN airport grounds 23Z-01Z. After 01Z, looks like we`ll settle
back to normal but slightly enhanced SSW winds 02Z-12Z. At KAPA,
there should be less threat of variable winds later this
afternoon, while KBJC almost certainly transitions more northerly.
KBJC will also have a reasonable shot of mountain wave winds with
gusts 25-30 kts after 09Z-10Z so we`ve added that to KBJC later
tonight.

On Thursday, winds will be the primary concern again, with
stronger gusts likely after 18Z as subsidence and mixing of
stronger WNW flow aloft occurs. This likely means 20G30+ kt winds
developing 18Z-19Z and continuing through 23Z. However, there`s a
small (20-30%) chance of an anticyclone disrupting the synoptic
scale flow pattern.

VFR conditions will continue thru the period.

&&

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

&&

$$

DISCUSSION...Danielson
AVIATION...20

NWS BOU Office Area Forecast Discussion