National Weather Service Forecast Discussion

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214
FXUS65 KBOU 010834
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
234 AM MDT Mon Jun 1 2026

.KEY MESSAGES...

- A chance for strong and severe thunderstorms this afternoon and
  again Tuesday afternoon, with locally heavy rain possible.

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

- Trending warmer and drier by the end of the week.

&&

.DISCUSSION /Through Sunday/...
Issued at 231 AM MDT Mon Jun 1 2026

Already seeing sct high based showers and a few weak tstms across
portions of nern CO early this morning.  This appears to be
associated with some mid level instability and along the srn portion
of an upper level jet.  Latest data suggest this activity will
continue thru mid morning with a few stronger storms possible closer
to the WY-NE border area.

By aftn, SW flow aloft will remain over the area as easterly flow in
the lower levels occurs behind a weak cool front.  SBCAPE over the
plains will range from 1500-2000 j/kg by aftn with a favorable shear
profile.  Sct tstms will develop near Denver by 20z and then move
rapidly ENE across the plains by 00Z.  Damaging winds and large hail
will likely occur with a few of the storms, with a brief tornado or
two possible initially, before storms consolidate into a solid line.
Meanwhile, across the higher terrain tstm coverage will be more
widely sct.  Highs today will be in the upper 70s to lower 80s
across the plains.

On Tue, the flow aloft will remain SW with the low level flow
becoming more SSE across the plains.  Once again, SBCAPE will range
from 1500-2000 j/kg with a favorable shear profile.  However, not
sure where best focus for tstms will be in the aftn.  If a Denver
cyclone were to develop, then storms may fire off the DCVZ and then
move ENE across the plains, with a few svr storms possible.  Once
again over the higher terrain expect tstm coverage will be more
isold to wdly sct.  As for highs, readings will be in the upper 70`s
to mid 80`s over the plains.

By Wed, the flow aloft will become more zonal and weaken. Meanwhile,
will still see SSE low level flow across the plains with possibly a
Denver cyclone and associated DCVZ.  SBCAPE will still be in the
1500-2000 j/kg range by aftn so there will still be some threat of
isold svr storms.  In addition, storm motions will be slower so may
see some heavier rainfall in those areas that get storms.   Across
the higher terrain, storm coverage will generally remain widely sct.
Highs over nern CO will be in the lower to mid 80`s.

For Thu and Fri, the flow aloft will remain nearly zonal as an upper
level trough moves across the nrn Rockies.  SBCAPE over the plains
will likely stay in the 1500-2000 j/kg range both days.  Overall,
focus for tstm development is hard to pinpoint this far out so will
just keep pops in the chc category.  Highs across the plains will
be in the 80`s on Thu with mid 80`s to lower 90`s by Fri.

Looking ahead to next weekend, an upper level trough is fcst to
develop over the wrn US with the flow aloft becoming more SSW.  For
now it looks drier with warmer temps.

&&

.AVIATION /06Z TAFS through 06Z Tuesday/...
Issued at 1119 PM MDT Sun May 31 2026

Latest data suggest a few sprinkles or virga will be possible
overnight with ceilings staying around 10000 ft thru 10z. For
now, don`t expect any microburst activity.  Winds will be light
and variable but become easterly around 12z as a weak cool front
moves across. By early Mon aftn, sfc winds will be mainly ESE with
a chc of tstms between 20z and 00z. At this time, activity looks
to be fairly sct so have maintained a prob30. There is a 10
percent chance of a stronger tstm affecting DIA as well. Ceilings
in the aftn will be around 10000 ft but may briefly drop to 6000
ft if a tstm moves across.  In addition, gusty outflow winds may
produce brieg gusts up to 40 mhp.

After 00Z tstm chances will decrease but can`t rule out a slight
chc of -shra. Winds will become more SE by early Mon evening.

&&

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

&&

$$

DISCUSSION...RPK
AVIATION...RPK

NWS BOU Office Area Forecast Discussion