Alert archive / Montana / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 79, NWS Glasgow, MT

July 9, 2018Daniels County, Roosevelt County, Montana

NWS Glasgow, MT issued this severe thunderstorm warning at Jul 9, 2018, 9:16 PM MDT for Daniels County, Roosevelt County, Montana. It was in force for 59 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
Jul 9, 2018, 9:16 PM MDT (03:16 UTC)
Expired
Jul 9, 2018, 10:15 PM MDT
In force
59 min
Issued by
NWS Glasgow, MT
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Daniels County, MT, Roosevelt County, MT

The radar

The Glasgow radar (KGGW), 106 km from the middle of the area, began a volume at 03:15 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Jul 9, 6:01 PM MDTSevere Thunderstorm WatchSPC8 hr

The nearest sounding before it

Glasgow Intl Airport, MT (KGGW), launched 00:00Z, 3.3 hours before the alert went out and 104 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-pSkew-T log-p diagram, Glasgow Intl Airport, MT at 00:00Z on 2018-07-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1794 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Glasgow Intl Airport, MT at 00:00Z on 2018-07-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 42 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
1794 J/kg
Mixed-layer CIN
-52 J/kg
Mixed-layer LCL
2264 m above ground
0-6 km bulk shear
51 kt
0-1 km storm-relative helicity
42 m²/s²
0-3 km storm-relative helicity
131 m²/s²
Significant tornado parameter
0.0
Supercell composite
4.2

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 Glasgow, MT wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 9, 2:33 PM MDT, 6 hours 43 minutes earlier.

Area forecast discussion, Jul 9, 2:33 PM MDT, 6 hours 43 minutes before
Area Forecast Discussion
National Weather Service Glasgow MT
233 PM MDT Mon Jul 9 2018

.DISCUSSION...

A strong upper-level ridge of high pressure air occupies much of
the west. The ridge axis will run over NE MT tonight. A storm
system off the Pac-NW coast will ride over the ridge tonight,
affecting our area Tuesday with strong storms. Today and evening,
there is a warm front over the area with good lapse rates and
cape in place. Thunderstorms are expected to develop along this
boundary, much of it in Saskatchewan. The areas of greatest
concern for strong storms is our northeast corner. The model
sounding shows vertical shear, and southeast surface flow to keep
the humidity higher in eastern zones.

Tuesday, our area has again been highlighted for Severe
Thunderstorms, this time Slight Risk. Again the strongest storms
may run east, north of the border, but produce storms mainly
across our northern zones, beginning in the late afternoon and
evening. Again, lapse rates and cape indicate a very unstable
environment. However in this case, the storm system brings a cold
front to set off storms.

Besides the storms, Tuesday is expected to be another hot day,
with highs around 100 again in some locations. With temperatures
again expected to rise into the high 90s and possibly triple
digits, heat risk again becomes an issue. Issued a Heat Advisory
for portions of the area. Also, with the expected wind and dry
conditions in Northern Valley & Phillips Counties, fire wx has
become a concern, especially based on the Drought Monitor
indicating Slight Drought conditions for those areas.  Templer

Previous Discussion for Wednesday and Beyond:
Temperatures cool about 15 degrees behind the front on Wednesday
as the upper trof moves through central Canada. Westerly flow
will keep the region dry, as temperatures slowly rebound.

By the end of the week, the next trof will drop into western
Canada. Cold front passage expected Friday night with
thunderstorms delayed until Saturday night, but confidence is not
high. Ebert

&&

.AVIATION...

Mainly VFR conditions expected over the next 24 hours.

A warm front could produce isolated thunderstorms that could
impact the TAF sites intermittently this afternoon, and tonight.
Some storms may become severe.

Tuesday, after a hot day, a cold front pushes through the area to
produce thunderstorms, some possibly severe, and strong wind.

Wind: east-southeast 10-20G30kt, becoming 10kt or less after
midnight. Wind will shift to the NW behind the cold front Tuesday
evening

&&

.GLASGOW WATCHES/WARNINGS/ADVISORIES...
Heat Advisory from noon to 8 PM MDT Tuesday for Central and
Southeast Phillips...Central and Southern Valley...Garfield...
McCone...Southwest Phillips...Western Roosevelt.

&&

weather.gov/glasgow

In the hours before

Local storm report, Jul 9, 8:09 PM MDT, 1 hour 7 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, Jul 9, 8:10 PM MDT, 1 hour 6 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, Jul 9, 8:31 PM MDT, 45 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, Jul 9, 8:57 PM MDT, 19 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, Jul 9, 8:58 PM MDT, 18 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, Jul 9, 9:07 PM MDT, 9 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 Glasgow, MT issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 9, 6:06 PM MDTSevere Thunderstorm WarningGGWSheridan54 min
Jul 9, 6:50 PM MDTTornado WarningGGWSheridan40 min
Jul 9, 6:56 PM MDTSevere Thunderstorm WarningGGWSheridan64 min
Jul 9, 7:24 PM MDTTornado WarningGGWSheridan51 min
Jul 9, 7:57 PM MDTTornado WarningGGWSheridan26 min
Jul 9, 8:08 PM MDTSevere Thunderstorm WarningGGWDaniels67 min
Jul 9, 8:19 PM MDTSevere Thunderstorm WarningGGWSheridan56 min
Jul 9, 8:52 PM MDTSevere Thunderstorm WarningGGWDaniels, Roosevelt, Sheridan53 min
Jul 9, 8:59 PM MDTSevere Thunderstorm WarningGGWRoosevelt, Sheridan46 min
Jul 9, 9:11 PM MDTSevere Thunderstorm WarningGGWSheridan20 min
Jul 9, 9:33 PM MDTSevere Thunderstorm WarningGGWRoosevelt, Sheridan27 min
Jul 9, 9:43 PM MDTSevere Thunderstorm WarningGGWDaniels, Roosevelt, Sheridan14 min
Jul 9, 10:03 PM MDTSevere Thunderstorm WarningGGWRichland, Roosevelt57 min
Jul 9, 10:07 PM MDTSevere Thunderstorm WarningGGWRoosevelt, Sheridan23 min
Jul 9, 10:18 PM MDTSevere Thunderstorm WarningGGWRoosevelt, Sheridan42 min
Jul 9, 10:54 PM MDTSevere Thunderstorm WarningGGWRichland, Roosevelt, Sheridan51 min
Jul 10, 4:05 PM MDTSpecial Weather StatementGGWPhillips40 min
Jul 10, 4:46 PM MDTSevere Thunderstorm WarningGGWPhillips59 min
Jul 10, 4:54 PM MDTSevere Thunderstorm WarningGGWPetroleum, Phillips66 min
Jul 10, 4:57 PM MDTSevere Thunderstorm WarningGGWPhillips, Valley63 min
Jul 10, 5:34 PM MDTSevere Thunderstorm WarningGGWPhillips, Valley56 min
Jul 10, 5:48 PM MDTSevere Thunderstorm WarningGGWDaniels, Phillips, Valley27 min
Jul 10, 5:54 PM MDTSevere Thunderstorm WarningGGWGarfield, Phillips, Valley66 min

Nearby

Severe Thunderstorm Warnings in Montana, 2018Every severe thunderstorm warning in 2018

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.