Alert archive / Utah / Severe Thunderstorm Warnings in 2025

Severe Thunderstorm Warning 49, NWS Grand Junction, CO

September 12, 2025San Juan County, Utah

NWS Grand Junction, CO issued this severe thunderstorm warning at Sep 12, 2025, 2:05 PM MDT for San Juan County, Utah. It was in force for 15 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Sep 12, 2025, 2:05 PM MDT (20:05 UTC)
Expired: Sep 12, 2025, 2:20 PM MDT
In force: 15 min
Issued by: NWS Grand Junction, CO
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

County San Juan County, UT

The radar

The Grand Junction radar (KGJX), 212 km from the middle of the area, began a volume at 20:07 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Flgstf/Belemont, AZ (KFGZ), launched 12:00Z, 8.1 hours before the alert went out and 321 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1323 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: 296 m²/s²
0-3 km storm-relative helicity: 350 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Grand Junction, CO wrote its last area forecast discussion before this severe thunderstorm warning went out at Sep 12, 11:24 AM MDT, 2 hours 41 minutes earlier.

Area forecast discussion, Sep 12, 11:24 AM MDT, 2 hours 41 minutes before

<!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>

Hazardous weather outlook, Sep 12, 4:12 AM MDT, 9 hours 53 minutes before

<!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>

In the hours before

Special weather statement, Sep 12, 1:27 PM MDT, 38 minutes before

<!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>

Special weather statement, Sep 12, 1:32 PM MDT, 33 minutes before

<!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>

Local storm report, Sep 12, 1:33 PM MDT, 32 minutes before

<!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>

Special weather statement, Sep 12, 1:52 PM MDT, 13 minutes before

<!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>

Local storm report, Sep 12, 1:53 PM MDT, 12 minutes before

<!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>

Local storm report, Sep 12, 1:55 PM MDT, 10 minutes before

<!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>

The office that day

Everything else NWS Grand Junction, CO issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Sep 11, 6:01 PM MDT	Special Weather Statement	GJT	Dolores	14 min
Sep 11, 6:15 PM MDT	Severe Thunderstorm Warning	GJT	Dolores, Montezuma, San Miguel	30 min
Sep 11, 7:16 PM MDT	Special Weather Statement	GJT	Ouray	14 min
Sep 11, 7:25 PM MDT	Special Weather Statement	GJT	Ouray	20 min
Sep 11, 8:13 PM MDT	Special Weather Statement	GJT	Delta	17 min
Sep 11, 8:21 PM MDT	Special Weather Statement	GJT	Delta	24 min
Sep 11, 8:26 PM MDT	Special Weather Statement	GJT	Delta	19 min
Sep 11, 9:13 PM MDT	Special Weather Statement	GJT	Garfield	17 min
Sep 11, 9:38 PM MDT	Special Weather Statement	GJT	Garfield	22 min
Sep 11, 10:40 PM MDT	Special Weather Statement	GJT		35 min
Sep 12, 4:44 AM MDT	Special Weather Statement	GJT	Dolores, San Miguel	31 min
Sep 12, 6:23 AM MDT	Special Weather Statement	GJT	Dolores	37 min
Sep 12, 8:10 AM MDT	Special Weather Statement	GJT	Montezuma	35 min
Sep 12, 8:47 AM MDT	Special Weather Statement	GJT		13 min
Sep 12, 8:59 AM MDT	Special Weather Statement	GJT		16 min
Sep 12, 9:23 AM MDT	Special Weather Statement	GJT		22 min
Sep 12, 9:42 AM MDT	Special Weather Statement	GJT	Rio Blanco	33 min
Sep 12, 9:44 AM MDT	Severe Thunderstorm Warning	GJT	Garfield, Mesa	31 min
Sep 12, 9:51 AM MDT	Severe Thunderstorm Warning	GJT	Dolores, La Plata, Montezuma, San Juan, San Miguel	24 min
Sep 12, 10:12 AM MDT	Severe Thunderstorm Warning	GJT	Hinsdale, La Plata, Ouray, San Juan	33 min
Sep 12, 10:15 AM MDT	Severe Thunderstorm Warning	GJT	Garfield, Mesa, Rio Blanco	30 min
Sep 12, 10:20 AM MDT	Special Weather Statement	GJT	Rio Blanco	25 min
Sep 12, 10:35 AM MDT	Areal Flood Advisory	GJT	San Juan	55 min
Sep 12, 10:39 AM MDT	Special Weather Statement	GJT	Rio Blanco	36 min
Sep 12, 10:43 AM MDT	Severe Thunderstorm Warning	GJT	Hinsdale, Ouray, San Juan	47 min
Sep 12, 10:45 AM MDT	Severe Thunderstorm Warning	GJT	Garfield, Rio Blanco	30 min
Sep 12, 10:52 AM MDT	Severe Thunderstorm Warning	GJT	Garfield, Mesa	23 min
Sep 12, 10:57 AM MDT	Special Weather Statement	GJT		18 min
Sep 12, 11:09 AM MDT	Severe Thunderstorm Warning	GJT	Montezuma	36 min
Sep 12, 11:12 AM MDT	Severe Thunderstorm Warning	GJT	Garfield, Mesa	33 min
Sep 12, 11:15 AM MDT	Special Weather Statement	GJT	Rio Blanco	30 min
Sep 12, 11:16 AM MDT	Special Weather Statement	GJT	San Juan	29 min
Sep 12, 11:38 AM MDT	Special Weather Statement	GJT	La Plata	37 min
Sep 12, 11:42 AM MDT	Flash Flood Warning Considerable damage threat	GJT	Rio Blanco	3 hr
Sep 12, 11:43 AM MDT	Special Weather Statement	GJT		32 min
Sep 12, 11:47 AM MDT	Special Weather Statement	GJT	Moffat	28 min
Sep 12, 11:50 AM MDT	Areal Flood Advisory	GJT	Garfield	3 hr
Sep 12, 12:10 PM MDT	Special Weather Statement	GJT	Routt	35 min
Sep 12, 12:18 PM MDT	Special Weather Statement	GJT	Garfield	27 min
Sep 12, 12:42 PM MDT	Special Weather Statement	GJT	Chaffee	33 min
Sep 12, 1:09 PM MDT	Special Weather Statement	GJT		36 min
Sep 12, 1:15 PM MDT	Special Weather Statement	GJT	Chaffee	15 min
Sep 12, 2:28 PM MDT	Severe Thunderstorm Warning	GJT	Mesa	32 min
Sep 12, 2:44 PM MDT	Severe Thunderstorm Warning	GJT	Mesa	31 min
Sep 12, 2:55 PM MDT	Special Weather Statement	GJT	Archuleta	35 min
Sep 12, 3:09 PM MDT	Severe Thunderstorm Warning	GJT	Garfield, Mesa	36 min
Sep 12, 3:11 PM MDT	Areal Flood Advisory	GJT	Mesa	64 min
Sep 12, 3:32 PM MDT	Areal Flood Advisory	GJT	Mesa	66 min
Sep 12, 3:36 PM MDT	Severe Thunderstorm Warning	GJT	Garfield, Mesa, Rio Blanco	24 min
Sep 12, 3:37 PM MDT	Special Weather Statement	GJT	Montrose	23 min
Sep 12, 3:44 PM MDT	Special Weather Statement	GJT	Mesa	31 min
Sep 12, 3:56 PM MDT	Special Weather Statement	GJT	Mesa	34 min
Sep 12, 3:59 PM MDT	Special Weather Statement	GJT	Garfield, Rio Blanco	46 min
Sep 12, 4:13 PM MDT	Flash Flood Warning Considerable damage threat	GJT	Rio Blanco	70 min
Sep 12, 4:21 PM MDT	Special Weather Statement	GJT	Mesa	24 min
Sep 12, 4:42 PM MDT	Special Weather Statement	GJT	Garfield	33 min
Sep 12, 5:14 PM MDT	Special Weather Statement	GJT	Routt	31 min
Sep 12, 5:44 PM MDT	Special Weather Statement	GJT	Routt	46 min
Sep 12, 8:05 AM MDT	Severe Thunderstorm Warning	GJT	Grand	40 min
Sep 12, 8:25 AM MDT	Special Weather Statement	GJT	Grand	35 min
Sep 12, 8:35 AM MDT	Areal Flood Advisory	GJT	Grand	115 min
Sep 12, 8:42 AM MDT	Severe Thunderstorm Warning	GJT	Grand	33 min
Sep 12, 8:50 AM MDT	Special Weather Statement	GJT	Grand	25 min
Sep 12, 9:02 AM MDT	Severe Thunderstorm Warning	GJT	Grand, San Juan	43 min
Sep 12, 9:12 AM MDT	Severe Thunderstorm Warning	GJT	Grand	33 min
Sep 12, 9:43 AM MDT	Flash Flood Warning	GJT	Grand	5 hr
Sep 12, 9:44 AM MDT	Severe Thunderstorm Warning	GJT	Grand	31 min
Sep 12, 9:54 AM MDT	Areal Flood Warning	GJT	Grand	51 min
Sep 12, 10:08 AM MDT	Special Weather Statement	GJT	Grand	22 min
Sep 12, 10:14 AM MDT	Special Weather Statement	GJT	Grand	31 min
Sep 12, 10:23 AM MDT	Severe Thunderstorm Warning	GJT	Grand	37 min
Sep 12, 11:21 AM MDT	Severe Thunderstorm Warning	GJT	Grand, San Juan	24 min
Sep 12, 11:46 AM MDT	Special Weather Statement	GJT	Grand	29 min
Sep 12, 11:51 AM MDT	Special Weather Statement	GJT	San Juan	24 min
Sep 12, 12:11 PM MDT	Special Weather Statement	GJT	San Juan	34 min
Sep 12, 12:12 PM MDT	Special Weather Statement	GJT	Grand	33 min
Sep 12, 12:18 PM MDT	Severe Thunderstorm Warning	GJT	San Juan	27 min
Sep 12, 12:22 PM MDT	Special Weather Statement	GJT	Grand	23 min
Sep 12, 12:25 PM MDT	Flash Flood Warning	GJT	San Juan	3 hr
Sep 12, 12:30 PM MDT	Severe Thunderstorm Warning	GJT	Grand	30 min

Nearby

Severe Thunderstorm Warnings in Utah, 2025 Every severe thunderstorm warning in 2025

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.