222
FXUS65 KBOU 010514
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1114 PM MDT Mon Jun 30 2025

.KEY MESSAGES...

- Summer heat returns Tuesday and Wednesday, still a few storms
  mainly over the mountains.

- Storm chances increase Thursday.

- Scattered thunderstorms and normal temperatures are expected for
  the Fourth of July and Independence Day weekend.

&&

.DISCUSSION /Through Monday/...
Issued at 217 PM MDT Mon Jun 30 2025

A few showers and thunderstorms had developed in the more
unstable airmass over the mountains this afternoon, but so far
coverage has been a little less than anticipated. We still think
South Park will end up with the highest coverage late this
afternoon into early evening. Some late day instability/weakening
CIN may allow a few showers/isolated storms to move onto the
adjacent plains south of I-70 (10-30% chance) early this evening.

For Tuesday and Wednesday, the center of the upper level ridge
will shift slowly east across Colorado, bringing a return of
summer warmth and a general decrease in shower/storm coverage.
However, there will be some moisture stuck under the ridge
Tuesday, and enough westerly flow aloft yet to allow a few high
based showers/storms to push east from the mountains onto the
plains. MLCAPE is limited (outside of the northeast corner) so
generally gusty winds and lightning would be the main threats. The
far northeast corner would have a low threat of severe with
MLCAPE 1000 J/kg or greater there. On Wednesday, the upper level
ridge is expected to shift slightly eastward into eastern
Colorado. Thus, with little/no westerly flow aloft it will be very
hard to get a storm on the plains. Mountain areas should still
see isolated to scattered late day convection.

For Thursday, we`ll still on track to see a plume of sub tropical
moisture move northward. This occurs in deeper southerly flow
developing between the upper level high shifting into the Central
and Southern Plains and a weak trough lifting northward across
the Desert Southwest. As a result, Thursday`s convective intensity
and coverage is expected to increase, with likely the best chance
(40-60%) of rain this week.

As discussed yesterday, there is also a threat that the
approaching trough from the southwest could end up being a player
on Independence Day weather. However, the latest trends over the
last 24 hours are for a faster and stronger ejecting trough
Thursday and Thursday night. If this occurs then that shortwave
could literally steal much of the thunder from Friday`s
(Independence Day) forecast. It`s still too early to tell, but the
latest trends would suggest a decrease in storm coverage and our
PoPs have been adjusted accordingly with this latest guidance.

Typical summer weather is then expected through next weekend, with
temperatures at/just above normal levels and a few rumbles of
thunder each afternoon and evening.

&&

.AVIATION /06Z TAFS through 06Z Wednesday/...
Issued at 1111 PM MDT Mon Jun 30 2025

Winds will stay mainly south overnight and then go more SSW by
13z. Expect light and variable winds by 17z whch will then shift
to SE by 21Z.  There will be sct hi based showers and tstms
after 21z with gusty outflow winds up to 40 mph.

&&

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

&&

$$

DISCUSSION...Barjenbruch
AVIATION...RPK