National Weather Service Forecast Discussion

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058
FXUS65 KBOU 070601
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1201 AM MDT Wed Oct 7 2026

.KEY MESSAGES...

- Unseasonably warm through at least Saturday.

- Only isolated to scattered showers (15-30% coverage) for the
  mountains and higher terrain. Any precipitation would be light.

- Pattern change late this weekend and early next week. Still
  considerable uncertainty as to when and how much temperatures
  will cool, and what chance of precipitation we`ll see.

&&

.DISCUSSION /Through Tuesday/...
Issued at 1049 PM MDT Tue Oct 6 2026

The upper level ridge that brought record/near record temperatures
to the forecast area the last two days will remain over the region
through Thursday. This means a continuation of unseasonably warm
weather, although the potential of record temperatures will drop
slightly Wednesday as we see just a slight push of easterly winds
across the plains. That will result in just a couple degrees of
cooling, with lower to mid 80s common for highs across the plains
both Wednesday and Thursday. Given a little moisture hanging under
the ridge, expect a similar convective scenario to Tuesday with
isolated to scattered light showers/isolated storms mainly over
the high country.

On Friday, we`ll start to get into west/southwest flow aloft as
the ridge starts to break down as an upper level trough moves into
the Pacific Northwest (PNW). This will support more downslope
flow and a continuation of very warm temperatures. In fact, this
could get us close (30-40% chance) of tying another record high on
either Thursday or Friday (Records are 85F and 87F, respectively).
With the increasing downslope, any isolated showers or storms
would be confined to the mountains.

There is excellent agreement that the warmth will persist for one
more day Saturday, before a pattern shift occurs. By Sunday, the
PNW trough is still forecast to drop southward across California,
picking up remnants of Hurricane Rachel. The trough has trended
deeper and farther west, which means the bulk of the precipitation
(some heavy) will once again end up falling over the Desert
Southwest into Utah and perhaps western Colorado. For the most
part, our forecast area will likely remain sheltered from any
significant precipitation. There are only a couple outliers with
heavier rain and mountain snow for us, and this might be because
of the handling of yet the next tropical storm which is still in
the very early stages of expected development. Thus, the best
chance of precipitation is now likely to hold off until Wednesday
or Thursday but a lot of uncertainty exists there. The uncertainty
surrounding temperatures also holds true, with some ensemble
members having a backdoor cool front reaching us Sunday or more
likely Monday. But given the farther west location of the upper
trough, it seems like the main push of cooler air would likely
get delayed. We`ll stick near the ensemble averages at this point
but should be worth noting that Monday`s highs could range
anywhere from the mid 40s to the mid 80s, with 25-75th percentiles
showing 60s-70s. A lot of spread but more confidence of cooling
to autum-like temperatures toward the middle of next week.

&&

.AVIATION /06Z TAFS through 06Z Thursday/...
Issued at 1158 PM MDT Tue Oct 6 2026

Winds are currently light (

NWS BOU Office Area Forecast Discussion