Flash Flood and Hail in South Dakota, June 8, 2018

Name: Flash Flood and Hail in South Dakota, June 8, 2018
Start: 2018-06-08T15:00
End: 2018-06-08T21:04
Location: South Dakota

June 8, 2018 · NWS UNR · 14 events in 5 counties and zones

Severe thunderstorms developed over Jackson County and eventually turned into a line of storms as they moved across south central South Dakota. The storms produced large hail and strong winds across the area.

Where it happened

Every event with a place to put it. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 14

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS UNR wrote it up.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Rapid City, SD wrote its last area forecast discussion before the first event at Jun 8, 1:43 PM MST, 1 hour 17 minutes earlier.

Area forecast discussion, Jun 8, 1:43 PM MST, 1 hour 17 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, Jun 8, 3:04 AM MST, 11 hours 56 minutes before

Hazardous Weather Outlook
National Weather Service Rapid City SD
404 AM MDT Fri Jun 8 2018

SDZ031-032-042>044-046-047-049-091300-
Pennington Co Plains-Haakon-Oglala Lakota-Jackson-Bennett-
Mellette-Todd-Tripp-
404 AM MDT Fri Jun 8 2018 /504 AM CDT Fri Jun 8 2018/

This Hazardous Weather Outlook is for portions of south central
South Dakota...and southwestern South Dakota.

.DAY ONE...Today and Tonight

Scattered thunderstorms are expected this afternoon into tonight.
There is an enhanced risk of severe thunderstorms. Large hail,
damaging winds and locally heavy rain will be the main threat. There
is also a small threat for tornadoes.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday

There is a chance of thunderstorms each day through the weekend.
There is a marginal risk of severe thunderstorms Saturday and
Sunday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed today.

&&

Stay tuned to NOAA weather radio for further updates...or check
our web site at weather.gov/rapidcity

SDZ013-014-024>030-041-072>074-WYZ057-058-091300-
Northern Meade Co Plains-Ziebach-Northern Black Hills-
Northern Foot Hills-Rapid City-Southern Foot Hills-
Central Black Hills-Southern Black Hills-Custer Co Plains-
Fall River-Sturgis/Piedmont Foot Hills-Southern Meade Co Plains-
Hermosa Foot Hills-Wyoming Black Hills-Weston-
404 AM MDT Fri Jun 8 2018

This Hazardous Weather Outlook is for portions of northwestern
South Dakota...southwestern South Dakota...the Black Hills of
South Dakota...northeast Wyoming...and the Black Hills of
Wyoming.

.DAY ONE...Today and Tonight

Scattered thunderstorms are expected this afternoon into tonight.
There is a slight risk of severe thunderstorms. Large hail,
damaging winds and locally heavy rain will be the main threat.
There is also a small threat for tornadoes.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday

There is a chance of thunderstorms each day through the weekend.
There is a marginal risk of severe thunderstorms Saturday and
Sunday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed today.

&&

Stay tuned to NOAA weather radio for further updates...or check
our web site at weather.gov/rapidcity

SDZ001-002-012-WYZ054>056-071-091300-
Harding-Perkins-Butte-Northern Campbell-Southern Campbell-
Western Crook-Northeastern Crook-
404 AM MDT Fri Jun 8 2018

This Hazardous Weather Outlook is for portions of northwestern
South Dakota...and northeast Wyoming.

.DAY ONE...Today and Tonight

Scattered thunderstorms are expected this afternoon and evening.
There is a marginal risk of severe thunderstorms. Large hail,
damaging winds and locally heavy rain will be the main threat.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday

There is a chance of thunderstorms each day through the weekend.
There is a marginal risk of severe thunderstorms Saturday and
Sunday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed today.

&&

Stay tuned to NOAA weather radio for further updates...or check
our web site at weather.gov/rapidcity

In the hours before

Local storm report, Jun 8, 2:32 PM MST, 28 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, Jun 8, 2:33 PM MST, 27 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, Jun 8, 2:45 PM MST, 15 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, Jun 8, 2:56 PM MST, 4 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, Jun 8, 2:58 PM MST, 2 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, Jun 8, 2:59 PM MST, 1 minute 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 radar

The Rapid City radar (KUDX), 95 km away, was scanning. The volume nearest the first event began at 22:00 UTC.

Open the radar archive at this moment

Event by event

9 thunderstorm wind, 4 hail, 1 flash flood. Local standard time, as filed.

Hail, Jackson

When: June 8, 3:00 PM MST to 3:05 PM MST
Where: Jackson County, 8.1 mi SE of Interior
Measured: 2 in hail
Reported by: Trained Spotter
Coordinates: 43.650, -101.850

Thunderstorm Wind, Jackson

When: June 8, 3:40 PM MST
Where: Jackson County, 7 mi E of Wanblee
Measured: 59 kt (68 mph) measured gust
Reported by: Mesonet
Coordinates: 43.570, -101.530

Hail, Jackson

When: June 8, 4:18 PM MST
Where: Jackson County, 3 mi E of Long Valley
Measured: 1.75 in hail
Reported by: Social Media
Coordinates: 43.460, -101.430

Thunderstorm Wind, Jackson

When: June 8, 4:23 PM MST
Where: Jackson County, 7 mi E of Wanblee
Measured: 50 kt (58 mph) measured gust
Reported by: Mesonet
Coordinates: 43.570, -101.530

Flash Flood, Jackson

When: June 8, 4:30 PM MST to 7:00 PM MST
Where: Jackson County, 9.63 mi ESE of Cedar Pass to 8.29 mi WNW of Wanblee
Cause: Heavy Rain
Reported by: Trained Spotter
Coordinates: 43.700, -101.770

Up to three inches of rain fell in a couple of hours along and near the White River in central Jackson County. Runoff from the heavy rain caused Pass Creek, Long Creek, Craven Creek, and Eagle Nest Creek to overflow their banks and flowed over Pass Creek Road. The White River south of Kadoka at SD Highway 73 quickly rose about eight feet and peaked around 8700 cfs due to the excessive runoff.

Hail, Mellette

When: June 8, 6:06 PM CST
Where: Mellette County, 5 mi ESE of Norris
Measured: 1.25 in hail
Reported by: Trained Spotter
Coordinates: 43.442, -101.108

Hail, Bennett

When: June 8, 5:31 PM MST
Where: Bennett County, 1 mi NW of Vetal
Measured: 0.75 in hail
Reported by: Trained Spotter
Coordinates: 43.230, -101.394

Thunderstorm Wind, Todd

When: June 8, 7:09 PM CST
Where: Todd County, 1 mi SE of Mission
Measured: 52 kt (60 mph) estimated gust
Reported by: Trained Spotter
Coordinates: 43.300, -100.646

Wind gusts were estimated at 60 mph.

Thunderstorm Wind, Tripp

When: June 8, 7:44 PM CST
Where: Tripp County, 4 mi SSE of Witten
Measured: 50 kt (58 mph) measured gust
Reported by: Mesonet
Coordinates: 43.377, -100.049

Thunderstorm Wind, Tripp

When: June 8, 7:45 PM CST
Where: Tripp County, 12.51 mi NW of Ideal
Measured: 55 kt (63 mph) measured gust
Reported by: Storm Chaser
Coordinates: 43.680, -100.040

Thunderstorm Wind, Tripp

When: June 8, 8:04 PM CST
Where: Tripp County, 5 mi N of Hamill
Measured: 52 kt (60 mph) estimated gust
Reported by: Trained Spotter
Coordinates: 43.672, -99.680

Wind gusts were estimated around 60 mph.

Thunderstorm Wind, Tripp

When: June 8, 8:05 PM CST
Where: Tripp County, 2 mi W of Hamill
Measured: 54 kt (62 mph) measured gust
Reported by: Mesonet
Coordinates: 43.600, -99.720

Thunderstorm Wind, Tripp

When: June 8, 8:30 PM CST to 8:35 PM CST
Where: Tripp County, 10.25 mi NE of Colome
Measured: 52 kt (60 mph) measured gust
Reported by: Storm Chaser
Coordinates: 43.370, -99.600

Thunderstorm Wind, Tripp

When: June 8, 9:04 PM CST
Where: Tripp County, Wewela
Measured: 50 kt (58 mph) measured gust
Reported by: Mesonet
Coordinates: 43.010, -99.780

What these are

Hail: Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.
Thunderstorm Wind: Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.
Flash Flood: Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in South Dakota in 2018 Every state in 2018 This day in weather history Warnings in South Dakota, June 2018

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-30. Each event’s entry at NCEI: 751475, 751476, 751477, 751478, 765140, 751479, 751480, 751481, 751482, 751483, 751484, 751485, 751486, 751487.