National Weather Service Forecast Discussion

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842
FXUS65 KBOU 200559
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1159 PM MDT Fri Jun 19 2026

.KEY MESSAGES...

- Isolated showers and thunderstorms possible near the southern
  foothills, Park County, and Palmer Divide today.

- Elevated fire weather conditions in the mountains and valleys
  today with critical conditions expected on Saturday.

- Strong to severe storms possible across the eastern plains on
  Saturday and Sunday.

- Scattered coverage of showers and storms on Sunday, Monday, and
  most of next week across the plains.

&&

.DISCUSSION /Through Friday/...
Issued at 131 PM MDT Fri Jun 19 2026

A cold front dropped south across eastern Colorado early this
morning bringing northerly winds and a slight increase
inmoisture. Denver ACARS soundings show precipitable water around
a half inch with a strong inversion. Expect this to limit
precipitation chances to Park County and the Palmer Divide where
those locations will have the best chance at breaking the cap.
Temperatures are currentlyin the 70s across northeast Colorado
and should top out in the lower to mid 80s. A surge of east-
northeast winds is expected this evening, originatingfrom the
thunderstorms currently over Nebraska. This will increase low
level moisture tonight and lead to low clouds late tonight and
Saturday morning across parts of northeast Colorado.

Warmer temperatures are expected Saturday with highs reaching the
mid 80s to lower 90s. This combined with the increased low level
moisture will lead to an unstable airmass over the eastern plains
with MLCAPE reaching 2000-3000 J/kg. Southwest flow aloft over the
easterlylow level will produce good shear as well. Bulk shear
(0-6km) reaches 40-50 knots, enough for supercell thunderstorms to
form. Very large hail, damaging winds, and isolated tornadoes
will be possible. The main threat for the strongest storms is
expected to be east of the urban corridor. Dry air will be just to
the west, over the mountains and foothills and the moist unstable
layer is expected to be shallow across the urban corridor. This
could change if the easterly push is stronger and deeper than
expected. The main threat window looks to be 3PM to 7PM. After
this, the strongest storms are expected to move east of the area.

For Sunday, we`ll see a shortwave trough pass north of Colorado
during the day. A cold front associated with this will drop south
across eastern Colorado during the afternoon hours. The best
chance for thunderstorms will be over the eastern plains where the
best moisture and instability will reside. A few of the storms
over the plains could be severe again as MLCAPE reaches 2000 J/kg.
Over the mountains and mountain valleys, dry westerly winds will
prevail. Highs are expected to reach the mid 80s to lower 90s
across northeast Colorado with the coolest temperatures over the
northeast corner.

For next week, an upper level high over the US/Mexico border will
intensify while westerly flow aloft continues over the Central
Rockies. The set up next week will be similar to this weekend with
dry air over the higher terrain and easterly low level flow over
the plains transporting moisture into the state. Each
afternoon/evening should bring a round of showers and
thunderstorms. The uncertainty being how far west the moisture and
thunderstorm development will be. Highs are expected to be in the
80s most days with Tuesday possibly being the coolest with highs
in the 70s.

&&

.AVIATION /06Z TAFS through 06Z Sunday/...
Issued at 1131 PM MDT Fri Jun 19 2026

VFR conditions expected for the next few hours before MVFR
conditions expected at DEN and APA in the early morning hours this
morning due to stratus deck coming in. VFR conditions will
gradually return through the morning.

Highly uncertain forecast in regards to wind direction for today
as a Denver cyclone will likely develop in the early morning
hours (08Z-10Z). This will bring a period of light and VRB winds
to DEN and APA for a period. Model guidance varies on the
evolution of the cyclone but generally expect ENE (and possibly
NW briefly) for both terminals throughout the morning. These
easterly winds will bring in a stratus deck, with ceilings as low
as 1500 ft. Expect stratus deck to erode by 17Z/18Z.

Afternoon showers and thunderstorms are expected to fire off a
boundary that should be east of all terminals by early afternoon.
however, have kept VCTS in the TAF for DEN and APA to account for
any storms that could initiate closer. Outflow winds will likely
impact both terminals, with VRB gusts up to 35 kts expected at
this time. As convection decreases into the evening, most guidance
favors north/northwest winds at all terminals. A front should
arrive around 03Z-05Z, which will then bring winds from the
northeast.


&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning from 11 AM to 9 PM MDT Saturday for COZ211>214-
217-218.

&&

$$

DISCUSSION...12
AVIATION...MAI

NWS BOU Office Area Forecast Discussion