National Weather Service Forecast Discussion

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057
FXUS65 KBOU 021755
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1155 AM MDT Tue Jun 2 2026

.KEY MESSAGES...

- A few severe storms will be possible again this afternoon, with
  locally heavy rain in a few areas.

- Thunderstorm chances will continue on Wednesday with lower
  threat for severe storms, however, locally heavy rain will be
  possible.

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

&&

.DISCUSSION /Through Monday/...
Issued at 257 AM MDT Tue Jun 2 2026

Tstms continue early this morning over portions of the east central
plains.  This area appears to be associated with an upper level and
has been anchored along some type of elevated boundary above the
sfc.  Activity may continue for a few more hours before ending by
11z.

For the rest of the day, WSW flow aloft will remain over the area
but will be somewhat weaker today. Meanwhile, at the sfc, the low
level flow will be more southerly across the plains. SBCAPE by
aftn will be in the 2000 j/kg range across nern CO. Main question
at this point is, where will tstm development focus by early to
mid aftn. There could be a DCVZ associated with a Denver cyclone
by early aftn which may act as a focus for sct tstm development.
In addition, may see a few storms develop closer to the Cheyenne
Ridge as well. Although shear profile won`t be as favorable this
aftn, decent SBCAPE should still allow for a few svr storms to
occur. Meanwhile, over the higher terrain tstm activity will
remain more widely sct. Highs this aftn will range from the upper
70`s to mid 80s over nern CO.

By tonight, will continue to see a few tstms across the plains early
this evening.  However, not sure if they will linger past midnight
like tonight.

On Wed, the flow aloft will be weak westerly.  At the sfc, winds
will remain mainly southerly across the plains.  However, there is
some disagreement as to whether there will be a convergence zone by
aftn from the Palmer Divide extending northeast across the plains.
If this convergence zone does develop then that would be a focus for
tstms development in the aftn.  SBCAPE along the boundary will be
around 2000 j/kg, however, overall shear will be weak.  However,
still can`t rule out an isold svr storm or two. In addition, with
weak flow, storms will be slow moving and produce heavy rainfall
in some areas. Meanwhile, over the higher terrain, tstm activity
will remain more widely sct. As for highs, readings will rise into
the mid to upper 80`s across the plains.

For Thu into Fri, mainly westerly flow aloft will be over the area.
SBCAPE both days will still be in the 1500-2000 j/kg range over
portions of the plains.  Thus still can`t rule out widely sct tstms
both days in the aftn over the plains.  Over the higher terrain,
activity should be more isold.  Highs over nern CO will continue to
rise with readings in the upper 80`s to lower 90s both days.

By the weekend, the flow aloft will gradually become more SW. This
will lead to even warmer temps as highs reach the lower to mid 90`s
across nern CO.  As far as tstm chances, for now will keep pops
mainly in the slight chc category.


&&

.AVIATION /18Z TAFS through 18Z Wednesday/...
Issued at 1155 AM MDT Tue Jun 2 2026

Storms and even clouds have struggled to survive moving off the
foothills over the past few hours. Satellite showing lift with a
weak wave over the higher terrain, but outflow from the earlier
storms has capped the airmass across the Denver area. There`s
still a threat for showers this evening, but thunderstorm chances
are low, less than 20 percent.

Low clouds will develop after midnight between 08Z and 10Z and
then linger most of Tuesday morning. Ceilings are expected to be
in the 1,000 to 3,000 foot range. A Denver cyclone may form
tonight and possibly cause winds to turn northwesterly at DEN and
APA. This may ceilings could fall to or below 1000 feet. Another
round of afternoon thunderstorms is expected, beginning 20-21Z.
There`s a chance the airmass is capped, with the best chance for
this occurring north of Denver.

&&

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

&&

$$

DISCUSSION...RPK
AVIATION...12

NWS BOU Office Area Forecast Discussion