Alert archive / Montana / Special Weather Statements in 2018

Special Weather Statement, NWS Great Falls, MT

May 17, 2018Fergus County, Montana

NWS Great Falls, MT issued this special weather statement at May 17, 2018, 2:16 PM MDT for Fergus County, Montana. It was in force for 29 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: May 17, 2018, 2:16 PM MDT (20:16 UTC)
Expired: May 17, 2018, 2:45 PM MDT
In force: 29 min
Issued by: NWS Great Falls, MT

County Fergus County, MT

The radar

The Billings radar (KBLX), 115 km from the middle of the area, began a volume at 20:18 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

Great_falls, MT (KTFX), launched 12:00Z, 8.3 hours before the alert went out and 130 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: 1319 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: -31 m²/s²
0-3 km storm-relative helicity: 48 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

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What forecasters said that day

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

NWS Great Falls, MT wrote its last area forecast discussion before this special weather statement went out at May 17, 11:15 AM MDT, 3 hours 1 minute earlier.

Area forecast discussion, May 17, 11:15 AM MDT, 3 hours 1 minute before

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<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>
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        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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In the hours before

Special weather statement, May 17, 2:14 PM MDT, 2 minutes before

Special Weather Statement
National Weather Service Great Falls MT
214 PM MDT THU MAY 17 2018

MTZ047-172100-
Blaine MT-
214 PM MDT THU MAY 17 2018

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHERN BLAINE COUNTY UNTIL 300
PM MDT...

At 212 PM MDT, Doppler radar was tracking a strong thunderstorm 26
miles southeast of Parker School, or 35 miles west of Zortman, moving
south at 5 to 10 mph.

Nickel size hail and winds in excess of 40 mph will be possible with
this storm.

This storm will remain over mainly rural areas of southern Blaine
County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Heavy rainfall is occurring with this storm. Additionally, the storm
is nearly stationary which could cause localized flooding. Do not
drive your vehicle through flooded roadways.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
office in Great Falls.

&&

LAT...LON 4795 10924 4811 10938 4843 10867 4820 10846
TIME...MOT...LOC 2012Z 012DEG 8KT 4803 10927

mpj

Special weather statement, May 17, 2:16 PM MDT, 0 minutes before

Special Weather Statement
National Weather Service Great Falls MT
216 PM MDT THU MAY 17 2018

MTZ051-172045-
Fergus MT-
216 PM MDT THU MAY 17 2018

...SIGNIFICANT WEATHER ADVISORY FOR SOUTH CENTRAL FERGUS COUNTY UNTIL
245 PM MDT...

At 216 PM MDT, Doppler radar was tracking a strong thunderstorm 20
miles south of Lewistown, moving northeast at 15 mph.

Half inch hail and wind gusts up to 50 mph will be possible with this
storm.

This storm will remain over mainly rural areas of south central
Fergus County.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 4675 10908 4675 10936 4678 10939 4702 10922
      4682 10891
TIME...MOT...LOC 2016Z 234DEG 13KT 4678 10926

KJ

The office that day

Everything else NWS Great Falls, MT issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 16, 6:12 PM MDT	Special Weather Statement	TFX		48 min
May 16, 7:06 PM MDT	Special Weather Statement	TFX		24 min
May 17, 11:32 AM MDT	Areal Flood Advisory	TFX	Lewis and Clark	48 hr
May 17, 12:44 PM MDT	Areal Flood Warning	TFX	Lewis and Clark	4 days
May 17, 2:14 PM MDT	Special Weather Statement	TFX	Blaine	46 min
May 17, 2:18 PM MDT	Special Weather Statement	TFX	Blaine	27 min
May 17, 2:36 PM MDT	Special Weather Statement	TFX	Fergus	39 min
May 17, 2:39 PM MDT	Flash Flood Warning	TFX	Blaine	4 hr
May 17, 3:00 PM MDT	Special Weather Statement	TFX	Musselshell	30 min
May 17, 3:13 PM MDT	Severe Thunderstorm Warning	TFX	Fergus	29 min

Nearby

Special Weather Statements in Montana, 2018 Every special weather statement 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.