670
FXUS65 KBOU 111120
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
520 AM MDT Mon Aug 11 2025

.KEY MESSAGES...

- Elevated fire conditions will continue over the higher terrain
  through Wednesday.

- Drier and warmer weather develops today and continues through
  Wednesday.

&&

.DISCUSSION /Through Sunday/...
Issued at 129 PM MDT Sun Aug 10 2025

Over the past couple hours, northeast winds have surged westward,
into the northern foothills. It`s been a little slow to make it
into the southern foothills. Outflow from convection to the
southwest of Denver will likely keep the best moisture out of the
southern foothills. A Severe Thunderstorm Watch has been issued
for much of eastern Colorado and most of the urban corridor
(except Jefferson County) where dew points are in the 50s (or
better), MLCAPE is 1000- 2000 J/kg and 0-6km Bulk Shear is 35-40
knots. These ingredients are expected to produce strong/severe
storms, including some supercell thunderstorms. Large hail to 2.5
inch in diameter and 70 mph will be the main threats. A tornado or
two is also possible. Isolated flash flooding will be possible
where multiple storms train over the same area. The Severe
Thunderstorm Watch runs until 8PM, afterwards storms should be
weaker. However, some models show a second round of weaker storms
mid to late evening, so will continue with decent (30- 60%) PoPs
for this.

For Monday, the upper level trough axis will be just east of the
area with a dry subsident northwest flow aloft. In addition to the
drier air in place, soundings show a strong mid level inversion,
around 450mb. This is expected to keep showers and storms from
developing on Monday. If this system slows a little, the southern
part of the forecast area could pick up a few showers and storms,
so will have low PoPs in these areas.

The upper level high begins to build over the area Tuesday and
will be centered over the Central Rockies Wednesday and at least
into early Thursday. Warmer air returns to the area under this
pattern with highs expected to reach the 90s Wednesday and
Thursday across northeast Colorado. Dry conditions are expected
for Tuesday and Wednesday with dry air over the area and the
subtropical moisture cut off from the area. On Thursday, the ridge
may drift eastward enough for the subtropical moisture to lift
northward into the area.

For Friday and next weekend, the upper level high will be over
the south central and southeast part of the country. This will
result in a weak south to southwest flow across the Central and
Southern Rockies. Subtropical (monsoon) moisture travels northward
into the area. Expected at least scattered afternoon/evening
thunderstorms in the mountains each day (Friday-Sunday) under this
pattern and possibly onto the plains. Temperatures take a step
back and will be closer to normal, which is upper 80s to lower 90s
over northeast Colorado.

&&

.AVIATION /12Z TAFS through 12Z Tuesday/...
Issued at 516 AM MDT Mon Aug 11 2025

There is some patchy fog to the north of DIA, over central Weld
county, early this morning but satellite has shown no movement to
the south. Thus have not mentioned any fog in the 12z Tafs.
Otherwise VFR conditions today and tonight. Winds were light south
to southeast but will trend light ENE by 16z. Winds by 20Z may
trend more NNE and then back to ENE by 01Z this evening. Late this
evening winds will go to the SE and then light drainage by 07z.

&&

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

&&

$$

DISCUSSION...Meier
AVIATION...RPK