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