928
FXUS65 KBOU 030557
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1157 PM MDT Wed Jul 2 2025

.KEY MESSAGES...

- Increased thunderstorm activity over the mountains Thursday
  afternoon and the plains Thursday evening.

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

&&

.DISCUSSION /Through Wednesday/...
Issued at 238 PM MDT Wed Jul 2 2025

Few changes to the forecast at this time, as weak convection
should be limited to the mountains today. South to southeast
steering winds should preclude anything drifting further east.
With CAPEs looking to be in the 400-800 J/kg range, threats should
be limited to subsevere gusty winds.

Mid level moisture will increase from the southwest on Thursday,
while low level moisture will increase from the southeast. This
will set the stage for a more active day, but the plains airmass
will likely remain capped most of the day. The strength of the
convection will still be limited by warm air aloft, but the
mountains should eventually see pretty good coverage of weak
convection, with a threat of gusty winds. On the plains, the storm
threat will likely wait until some combination of outflow from the
mountains, or more likely the shortwave aloft that will bring some
lift in the evening, and possibly lingering overnight in the
northeast corner. There could be up to 1000 J/kg of CAPE for the
plains in the evening, but with little shear, the threats are
mainly subsevere wind gusts, and possibly localized heavy rain if
there gets to be some organization to slow moving storms.

The timing of the shortwave Thursday night sets up an interesting
pattern for the Fourth of July. We`ll likely have convection
exiting in the early morning hours, and drying northwest flow
aloft by afternoon. There will also be some cooling aloft though,
enough to allow for another round of convection in the slightly
cooler and drier airmass. We`re hanging on to scattered
afternoon/early evening PoPs, but if the drying is enough there
may be less activity or a quicker end. In any event, it doesn`t
look like a particularly active day in terms of coverage or
intensity.

For the weekend and beyond, there are just subtle day to day
changes as we`ll be under a mean ridge with a couple of shortwaves
moving over the top of it. There`s enough variety in the low and
mid level moisture in the models to make it hard to pin down
details, though there is some tendency towards a little more
thunderstorm activity Sunday and Monday and then warming and
drying after that as the mean ridge strengthens. Overall, fairly
typical early July weather with lower elevation highs mostly in
the lower to mid 90s for an extended period and some threat of
storms each day.

&&

.AVIATION /06Z TAFS through 06Z Friday/...
Issued at 1152 PM MDT Wed Jul 2 2025

Models show weak drainage winds overnight at DIA, with some of
them showing wind directions to be a tad east of due south for at
least half of the overnight period. Weak southeasterly winds are
progged from mid/late morning Thursday into the early evening
hours. A couple models have a slight chance of pops at DIA
Thursday evening, but most models keep the showers and storms in
the mountains and foothills only.  Will leave mention of TS out
for now. There will be no ceiling issues.


&&

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

&&

$$

DISCUSSION...Gimmestad
AVIATION.....rjk