National Weather Service Forecast Discussion

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746
FXUS65 KBOU 132037
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
237 PM MDT Sat Jun 13 2026

.KEY MESSAGES...

- Cool temperatures today and Sunday behind a cold front.

- The best chances for showers/thunderstorms will be Sunday mainly
  along and south of I-70.

- Temperatures heat back up next week.

- Increasing fire weather concerns on Tuesday and Wednesday.

&&

.DISCUSSION /Through Saturday/...
Issued at 145 PM MDT Sat Jun 13 2026

A cold front moved through eastern Colorado last night with cool,
northeast winds behind it. With dry air aloft helping to keep
conditions mostly sunny, it is a pleasant day for June across most
of the northern half of Colorado. Low level convergence over the
Palmer Divide, southern foothills, and South Park may help to
create a few showers in those locations late this afternoon and
evening.

The next round of even cooler air will arrive tonight in our
forecast area. Low clouds currently in Wyoming are associated
with a nearby shortwave trough. Temperatures in Wyoming under
these clouds are mostly in the 40s and low 50s. This will move
into Colorado late this evening. Highs on Sunday are expected to
stay in the 60s across the plains tomorrow with mostly clouds
skies. The upslope flow will likely create some drizzle in the
foothills and adjacent plains. By the afternoon, there will be
enough instability in the central mountains that showers and a few
thunderstorms will form. The best chance for accumulating
rainfall will be along and south of I-70. These storms are not
expected to be severe due to lack of instability.

Ridging aloft will move over Colorado on Monday providing
subsidence. Temperatures will moderate from Sunday`s cool
conditions but will remain below normal.

West-northwesterly flow aloft will increase on Tuesday and
Wednesday as 700 mb temperatures will warm rapidly. 700 mb
temperatures will likely be around 17-18 C over Denver on Tuesday
and near 20 C on Wednesday. This will lead to hot temperatures
around 90 across the plains on Tuesday and the mid 90s on
Wednesday. There will be very dry conditions and moderate
downslope winds. Fire weather concerns will increase Tuesday and
Wednesday with Wednesday potentially reaching critical levels.

A sharp surface cold front will move through Colorado Wednesday
night. This will drop temperatures to more seasonal levels on
Thursday. The CPC and ensembles show a wetter pattern for Colorado
by next weekend and into early the following week. There is some
skepticism that there will be wetter than normal conditions at
this point.

&&

.AVIATION /18Z TAFS through 18Z Sunday/...
Issued at 1205 PM MDT Sat Jun 13 2026

Winds are currently NNE with a few gusts up to 20KT being
observed. Some stronger (25-30KT) gusts will be possible with a
reinforcement of the NE winds between 23Z and 02Z, as well as an
isolated shower. The shower potential this evening still looks to
be rather low (

NWS BOU Office Area Forecast Discussion