National Weather Service Forecast Discussion

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070
FXUS65 KBOU 040852
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
252 AM MDT Thu Jun 4 2026

.KEY MESSAGES...

- Trending warmer and drier for today and Friday with only a
  slight chance of thunderstorms.

- Afternoon high temps to reach the mid 90s across the plains this
  weekend.

&&

.DISCUSSION /Through Wednesday/...
Issued at 249 AM MDT Thu Jun 4 2026

The flow aloft will become more WNW today with some decrease in low
level moisture across the plains.  However, the far nern plains will
still have SBCAPE in the 1500-2000 range during the aftn.  As a
result, could see an isold stg/svr storm during the late aftn/early
evening hours over the far northeast corner.  Otherwise, further
west, any shower/tstm activity will be high based and may produce
gusty winds with DCAPE around 1000 j/kg. As for highs, readings
will be warmer across nern CO as highs rise into the mid 80`s to
lower 90`s.

On Fri, the flow aloft will become more westerly. A weak cool front
will move across the plains in the morning with easterly low level
flow by aftn.  Have mentioned a slight chc of tstms from South Park,
across the srn foothills and Palmer Divide for late aftn thru the
early evening hours. A few stronger storms are certainly possible
due to SBCAPE around 1500 j/kg along with favorable shear.  Highs on
Fri will be in the mid 80`s to around 90.

For Sat, weak SW flow aloft will be over the area.  Models have some
mid level moisture in the flow so can`t rule out widely sct high
based showers and storms mainly over the higher terrain. Highs
will be warmer on Sat as readings rise into the low to mid 90`s
across the plains.

By Sun, WSW flow aloft will develop with a sfc lee trough over the
plains.  This will lead to another very warm day with readings in
the mid to upper 90`s across the plains.  Meanwhile, if there is
some moisture embedded in the flow, may see a slight chc of higher
based showers/tstms in the aftn and evening hours.

Looking ahead to Mon, a cool front is fcst to move across the plains
which may drop temps back into the 85 to 90 degree range. As for
tstm chances, it will depend on whether a capping inversion can be
broken or not.  For now have kept pops in the 20-30 percent range.

For the middle part of next week, an upper level trough will be over
the Pacific NW with rather stg WSW flow aloft over the area. This
will lead to warmer temps as readings rise well into the 90`s across
nern CO.  Overall it looks mainly dry both days, although can`t rule
out a few isold storms over portions of the plains where decent
instability will exist ahead of a pseudo dryline.

&&

.AVIATION /06Z TAFS through 06Z Friday/...
Issued at 1113 PM MDT Wed Jun 3 2026

VFR conditions thru the period. Drainage winds overnight will
become more WSW by 14z.  Winds will then trend to northerly
by 18z.  There will be a slight chc of high based showers
by 20Z thru 01z. Brief gusty outflow winds from 35 to 40 mph will
be possible. Winds will shift to more southerly by 01z Thu
evening.

&&

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

&&

$$

DISCUSSION...RPK
AVIATION...RPK

NWS BOU Office Area Forecast Discussion