National Weather Service Forecast Discussion

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794
FXUS65 KBOU 050932
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
332 AM MDT Sun Jul 5 2026

.KEY MESSAGES...

- A few storms expected each day of the coming week, with the
  highest probabilities shaping up for Tuesday and Wednesday from
  the Front Range eastward.

- Isolated dry thunderstorms in mountains could spark new
  wildfires.

- Good agreement that significant heat wave arrives by next
  weekend.

&&

.DISCUSSION /Through Saturday/...
Issued at 127 AM MDT Sun Jul 5 2026

Summer warmth will continue today as upper-level ridging builds
across the Rockies. This will warm afternoon high temps a few
degrees over Saturday`s with 90s forecast across the plains, 70s
and 80s for our mountain valleys. We will have less moisture to
work with, but there will still be enough for some high-based
showers/weak storms in the afternoon and evening, mainly for the
southern foothills and Palmer Divide. The main concerns will be
with gusty outflows/microbursts, as DCAPE is expected to range
between roughly 1200-1600 J/kg. Overnight low temperatures are
forecast to be 5 to 10 degrees above normal, with 50s and 60s
expected for the plains, and 40s for our mountain valleys.
Guidance suggests patchy smoke will creep back northward along the
Front Range and urban corridor with overnight southerly winds
tonight that will make for some potential hazy skies on Monday.

700mb temperatures will increase by about 4 degrees C on Monday as
the ridge persists, translating to afternoon high surface temps
warming a few more degrees over Sunday`s. There will be a slight
chance for showers and weak storms once again, with the best
chances along the Front Range, Palmer Divide, and Cheyenne Ridge.

Precipitation chances will increase Tuesday through Thursday as
PWAT values are expected to increase to above normal values.
Instability and shear are looking to increase to values worthy of
supporting at least a few stronger to severe storms on Wednesday
and Thursday (30-35kts bulk shear and 500-1200 J/kg of MLCAPE),
with upper-level support from passing shortwaves to the north.
These shortwaves will flatten the ridge for mid-week, but it`s
looking like it will build back with force by the weekend.

There is still consistent agreement amongst guidance with 500 mb
heights showing highly significant +2.0 to +2.5 sigma anomaly,
representing an extreme high pressure ridge that will likely bring
significant subsidence and low-level warming and drying across
the forecast area. Ensemble means continue to show well-above
normal temperatures by Saturday afternoon, and near record-breaking
temperatures possible Sunday (KDEN record high for 7/12 is 102F
and the current forecast high is 101F).


&&

.AVIATION /06Z TAFS through 06Z Monday/...
Issued at 1140 PM MDT Sat Jul 4 2026

Southerly winds are in place at KDEN/KAPA late tonight, with some
gusts between 20-25kts just off the deck at KDEN. Should see winds
between 15-20kts for the next few hours before winds transition to
the SSW and weaken by 8-10Z.

The main concern for the TAF period will be the potential for
some gusty high-based virga showers in the afternoon, with KAPA
having the best chance for precipitation with anything that
develops. Instability is expected to be marginal, with just enough
for a brief thunderstorm to develop in the southern foothills
that could bring a TS close to KAPA, though there is slightly
higher confidence that anything that forms would weaken before it
makes it to the terminal. As it weakens, there would be potential
for -SHRA with gusty outflows between 25-35kts with enough DCAPE
(1200-1500 J/kg) to support microbursts. While there is higher
confidence for impacts at KAPA, there is still a non-zero chance
KDEN sees some gusty outflows, but there is not enough confidence
to put in the TAF at this time.

Hi-res guidance suggests that smoke will increase along the Front
Range towards the end of the TAF period (late Sunday night),
therefore have reintroduced it into the TAF with the expectation
we see some slant-range vis concerns return by sunrise Monday
morning.

&&

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

&&

$$

DISCUSSION...9
AVIATION...9

NWS BOU Office Area Forecast Discussion