628
FXUS65 KBOU 180607
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1207 AM MDT Tue Aug 18 2026

.KEY MESSAGES...

- Scattered showers and thunderstorms expected Tuesday and
  Wednesday. Isolated severe thunderstorm threat both afternoons
  and evenings.

- Above normal temperatures through the weekend. Drier Thursday
  and Friday, but some monsoonal moisture likely returns by the
  weekend.

&&

.DISCUSSION /Through Monday/...
Issued at 125 PM MDT Mon Aug 17 2026

Drier zonal flow aloft is now over most of the state today... and
unsurprisingly that has led to warmer temperatures across the
region, along with far less convection over our forecast area.
We`ve seen a return to 90s today (92F at DEN so far), with dew
points back down into the 30s across the metro. We haven`t
completely mixed out the boundary layer moisture across the
northern I-25 corridor and over the easterly plains, where there
are still mid/upper 50s dew points and modest MLCAPE. Guidance
still tries to spit out a couple of showers or thunderstorms
there and the environment would support a couple of stronger
storms assuming we get a real attempt at CI at some point this
afternoon.

A weak cold front is still on track to arrive sometime late
Tuesday morning, which should introduce some better surface
moisture to the I-25 corridor. The increased instability (along
with increasing deep layer shear) will promote at least widely
scattered thunderstorms, and it wouldn`t be surprising to see a
couple strong to severe storms yet again during the afternoon...
especially over the eastern plains.

Stronger ridging is expected to develop during the latter half of
the week, though we won`t see temperatures climb nearly as high as
we did with our previous ridge. Forecast highs will return back
into the mid 90s for the Denver metro with generally dry
conditions.

As we head into the weekend or early next week, the ridge is
expected to briefly weaken and shift into a slightly more
favorable location for monsoon moisture to make a brief return.
Both Sunday and Monday have higher PoPs, though once again the
NBM is likely a bit too bullish with PoP coverage across most of
our forecast area.

&&

.AVIATION /06Z TAFS through 06Z Wednesday/...
Issued at 1145 PM MDT Mon Aug 17 2026

Drainage winds will generally prevail for the next couple of
hours. Winds will start to turn more west/northwest around 08Z to
09Z, before becoming variable around 15Z to 16Z. Light and
variable winds will continue for the late morning to early
afternoon until stronger northeasterly winds move into the area
behind a weak cold front. Scattered showers and thunderstorms are
expected this afternoon. Uncertainty is still pretty high in both
coverage and location of this activity, so we`ve left the prob30
in there for now. But, we may need to update that to a TEMPO if
models continue to trend up with storm coverage Tuesday afternoon
and evening. There`s also a question on how long the showers and
storms will linger across the area before moving off to the
east/southeast, with some models keeping them around into the
early overnight hours.

&&

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

&&

$$

DISCUSSION...Hiris
AVIATION...AP

NWS BOU Office Area Forecast Discussion