National Weather Service Forecast Discussion

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452
FXUS65 KBOU 131943
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
143 PM MDT Mon Jul 13 2026

.KEY MESSAGES...

- Hot weather through the entire week ahead. Heat Advisory in
  effect today for the I-25 Corridor.

- Only hints of monsoonal moisture reaching the high country by
  late in the week or next weekend.

- Prolonged hot and dry conditions will bring fire weather
  concerns, although we`ll likely stay just shy of Red Flag
  criteria most days.

&&

.DISCUSSION /Through Monday/...
Issued at 1249 PM MDT Mon Jul 13 2026

The heat is in full swing across the state of Colorado. Downtown
Denver along with many other urban areas across the I-25 corridor
are expected to reach around 100 degrees this afternoon. Usually,
there are afternoon clouds that move off the higher terrain and
provide some relief from the heat for the I-25 corridor. However,
for today and much of this week, there will be a slight easterly
component to the upper level winds that will keep the clouds over
the higher terrain and not over the I-25 corridor. The
temperatures, along with the sunshine, resulted in our office
issuing a Heat Advisory for the I-25 corridor today which is in
effect through 9pm.

While the heat may not reach advisory levels across the higher
terrain, high temperatures today may break all-time record highs.
All-time record highs in Middle Park are in the low to mid 90s
and our forecast calls for values in that range. The AWOS at
Kremmling is already at 90 degrees at 1pm.

There is slightly less of a mid level cap today and with slight
moisture advection, there will be some isolated showers and storms
in the higher terrain. Some dry lightning strikes could occur
which is a concern that a fire or two could start. PoPs were
increased in the southern foothills to include a slight chance of
storms in the forecast since some of the storms that form near the
Continental Divide could produce outflows that develop storms to
the east.

Very similar weather conditions will exist over our forecast area
for the rest of the work week. This is because a large longwave
ridge will continue to be over the central US providing subsident
flow. However, there will be slightly cooler temperatures by 2-3
degrees for the rest of the week as a weak trough will move
westward underneath the broader ridge. This will increase moisture
in the low levels and slightly decrease temperatures in the
700-500 mb layer. Isolated to scattered showers and storms will
form over the higher terrain each day. With the east winds aloft,
there is a very low chance that any storms move onto the plains.

The upper level ridge will move back directly over Colorado this
upcoming weekend which may increase temperatures back towards
99-100 in Denver. Depending on the location of the center of the
ridge, a Heat Advisory may be considered again. The chances of a
Heat Advisory would increase if there are more easterly winds
aloft and less cloud cover.

Beginning next work week, higher moisture values will make it to
northern Colorado. Global ensembles are showing that this period
will have more normal or slightly above normal precipitation but
at this range there is not a lot of confidence in the higher
rainfall amounts.


&&

.AVIATION /18Z TAFS through 18Z Tuesday/...
Issued at 1147 AM MDT Mon Jul 13 2026

VFR will persist through the TAF period. Southeast winds are
expected to increase again with gusts to 24-30 kts expected at
KDEN and KAPA 21Z-09Z, before gradually weakening late tonight and
turning more southerly. KBJC will see a more easterly component
early in the period (on the back side of a weak shear zone
straddling metro Denver), with southeast winds expected to
eventually develop and increase with gusts 18-24 kts 23Z-04Z.
Winds are expected to become light for a few hours 13Z-17Z before
E-SE winds increase again Tuesday.

We will see isolated showers/storms develop over the Front Range
with sufficient moisture and instability. However, any storms are
expected to stay confined to the higher elevations, but a low
risk (20% chance) of an outflow reaching KBJC.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 9 PM MDT this evening for COZ038>040.

&&

$$

DISCUSSION...Danielson
AVIATION...20

NWS BOU Office Area Forecast Discussion