Severe Thunderstorm Warning 276, NWS Denver/Boulder, CO

Area Forecast Discussion
National Weather Service Denver/Boulder CO
202 PM MDT Sat Aug 2 2025

.KEY MESSAGES...

- A few severe thunderstorms are possible this afternoon/early
  evening east of a line from Limon to Sterling.

- Gusty showers and thunderstorms through this evening. Brief
  moderate to heavy rain also possible.

- Dry and hot early to mid next week, with increasing fire danger
  Jackson and Grand Counties.

&&

.DISCUSSION /Through Saturday/...
Issued at 202 PM MDT Sat Aug 2 2025

Drier air has spread eastward over much of the area today with
precipitable water values under 0.75 (in) pushing readings at or
below normal. A shortwave trough is moving across the area and is
triggering scattered showers and thunderstorms. The drier air is
leading to MLCAPE of about 500 J/kg. The storms will be higher-
based and are expected to produce gusty outflow winds with brief
moderate to heavy rain. DCAPE values are 1000-1500 J/kg, so gusty
winds will continue to be the main threat with a few gusts of
50-60 mph. A surface trough/dry line runs roughly from Limon to
Sterling. East of this line, moisture increases with dew points
into the upper 50s to lower 60s. MLCAPE is 1500-2500 J/kg with
30-40 knots of bulk shear (0-6km). This should produce a few
strong to severe storms this afternoon and evening. The showers
and storms linger into the evening hours as the shortwave
continues to provide lift. By midnight, most/all of the showers
and storms should have ended.

A weak cold front pushes south through the area Sunday morning.
This will bring slightly cooler temperatures and drier air.
Precipitable water values fall to 50-80 percent of normal. A few
of the hi-res models show isolated storms over far northern and
eastern Colorado where a little better moisture may reside. Will
have some low PoPs in the forecast for this, otherwise expect dry
conditions.

The upper level high to the south builds northward over the
Central Rockies Monday. Temperatures climb into the lower to mid
90s across northeast Colorado. Airmass dries more with
precipitable water values 40-70 percent of normal. Some low level
moisture hangs on over far eastern Colorado. However, soundings
show it should be very shallow. Will keep the mention for storms
out of the forecast for Monday over far eastern Colorado, but
can't totally rule out a strong late day storm.

With the high firmly overhead for Tuesday and Wednesday, highs
will be in the mid to lower 100s. Dry air will remain over
Colorado with only a slim (less than 15% chance) for a
strong/severe storm over far eastern Colorado if there's enough
low level moisture.

For Thursday through Saturday, the upper level high weakens and
drifts south as a large upper level tough moves over the Pacific
Northwest and Northern Rockies. There's some difference on how
quickly the high exits the area, which isn't surprising this far
out. Thursday is expected to stay very warm and possibly into
Friday as well. As the highs drifts south, we should see a gradual
increase in moisture by Friday and Saturday (possibly Thursday
according to the ECMWF). This should bring at least high-based
showers and storms back to the area with better moisture possible
for next weekend.

&&

.AVIATION /18Z TAFS through 18Z Sunday/...
Issued at 1138 AM MDT Sat Aug 2 2025

Showers and thunderstorms will increase over the next couple of
hours becoming scattered by 19-20Z. The showers/storms will mainly
be high-based with gusty outflows up to 45 knots. Wind shifts
(possibly several) are possible 20z to 02Z. Any storm is expected
to be short-lived with brief heavy rain also possible.

The showers and thunderstorms end early to mid evening. Skies
slowly clear overnight with mostly clear skies for Sunday. Winds
become a southerly drainage direction this evening and stay
southerly into Sunday morning. A dry cold front is expected to
arrive around 15Z bringing a wind shift to the north.

&&

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

&&

DISCUSSION...Meier
AVIATION...Meier

Hazardous Weather Outlook
National Weather Service Denver/Boulder CO
954 AM MDT Sat Aug 2 2025

COZ030>051-031600-
Jackson County Below 9000 Feet-
West Jackson and West Grand Counties Above 9000 Feet-
Grand and Summit Counties Below 9000 Feet-
South and East Jackson/Larimer/North and Northeast Grand/
Northwest Boulder Counties Above 9000 Feet-
South and Southeast Grand/West Central and Southwest Boulder/
Gilpin/Clear Creek/Summit/North and West Park Counties Above
9000 Feet-Larimer and Boulder Counties Between 6000 and 9000 Feet-
Jefferson and West Douglas Counties Above 6000 Feet/Gilpin/Clear
Creek/Northeast Park Counties Below 9000 Feet-
Central and Southeast Park County-
Larimer County Below 6000 Feet/Northwest Weld County-
Boulder And Jefferson Counties Below 6000 Feet/West Broomfield
County-
North Douglas County Below 6000 Feet/Denver/West Adams and
Arapahoe Counties/East Broomfield County-
Elbert/Central and East Douglas Counties Above 6000 Feet-
Northeast Weld County-Central and South Weld County-Morgan County-
Central and East Adams and Arapahoe Counties-
North and Northeast Elbert County Below 6000 Feet/North Lincoln
County-
Southeast Elbert County Below 6000 Feet/South Lincoln County-
Logan County-Washington County-Sedgwick County-Phillips County-
954 AM MDT Sat Aug 2 2025

This hazardous weather outlook is for northeast and north central
Colorado.

.DAY ONE...Today and Tonight

Scattered showers and thunderstorms will develop over the
mountains late this morning and early this afternoon and then
push east across the plains this afternoon and early evening.
Brief heavy rain, small hail, and wind gusts to 50 mph will be
possible with the storms today. A few storms could become severe
east of a line from Limon to Sterling with large hail and strong
winds.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

A drier airmass spreads back across the region Sunday and for next
week. Temperatures will warm to above normal Monday and stay above
normal for next week.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated today or tonight. However,
any reports of damaging winds, hail, or heavy rain will be
appreciated.

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>