National Weather Service Forecast Discussion

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372
FXUS65 KBOU 172038
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
238 PM MDT Mon Aug 17 2026

.KEY MESSAGES...

- Warming trend for today and Tuesday, with isolated to scattered
  showers and thunderstorms.

- More active weather day shaping up for Wednesday with scattered
  severe thunderstorm threat.

- Warmer again through the coming weekend with above normal
  temperatures. 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 /18Z TAFS through 18Z Tuesday/...
Issued at 1128 AM MDT Mon Aug 17 2026

VFR conditions are expected today. While there is some instability
out there today, ACARS soundings are rather capped and most
guidance struggles to develop much more than some scattered mid-
level clouds this afternoon. Winds should remain weak and out of
the east through most of the afternoon before transitioning back
to drainage around 03-05z, which will prevail through the
overnight hours.

Winds will weaken and start to turn clockwise during the morning
hours Tuesday. A wind shift/cold front is expected to arrive near
or just after 18z Tuesday with slightly stronger northeast flow
following it.

&&

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

&&

$$

DISCUSSION...Hiris
AVIATION...Hiris

NWS BOU Office Area Forecast Discussion