Hail and Damaging Winds in South Dakota, July 18, 2018

Name: Hail and Damaging Winds in South Dakota, July 18, 2018
Start: 2018-07-18T13:48
End: 2018-07-18T14:58
Location: South Dakota

July 18, 2018 · NWS UNR · 9 events in 3 counties and zones

A severe thunderstorm developed near Rapid City and tracked southeast into Oglala Lakota County before weakening. The storm produced large hail and wind gusts to 70 mph.

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: 9

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.

A severe thunderstorm developed near Rapid City and tracked southeast into Oglala Lakota County before weakening. The storm produced large hail and wind gusts to 70 mph.

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 Jul 18, 12:55 PM MST, 53 minutes earlier.

Area forecast discussion, Jul 18, 12:55 PM MST, 53 minutes before

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Hazardous weather outlook, Jul 18, 6:36 AM MST, 7 hours 12 minutes before

Hazardous Weather Outlook
National Weather Service Rapid City SD
736 AM MDT Wed Jul 18 2018

SDZ046-047-049-191315-
Mellette-Todd-Tripp-
836 AM CDT Wed Jul 18 2018

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

.DAY ONE...Today and Tonight

Scattered showers and thunderstorms are expected again today.
Severe storms capable of producing damaging winds, large hail,
and tornadoes will be possible.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday

No hazardous weather is expected at this time.

.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>014-024>026-028>032-042>044-072>074-191315-
Harding-Perkins-Butte-Northern Meade Co Plains-Ziebach-
Northern Black Hills-Northern Foot Hills-Rapid City-
Central Black Hills-Southern Black Hills-Custer Co Plains-
Pennington Co Plains-Haakon-Oglala Lakota-Jackson-Bennett-
Sturgis/Piedmont Foot Hills-Southern Meade Co Plains-
Hermosa Foot Hills-
736 AM MDT Wed Jul 18 2018

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

.DAY ONE...Today and Tonight

Isolated showers and thunderstorms are expected again today. A few
storms may be severe, with damaging winds and large hail the
primary concerns. Locally heavy rainfall will be possible in any
thunderstorms.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday

No hazardous weather is expected at this time.

.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

SDZ027-WYZ057-071-191315-
Southern Foot Hills-Wyoming Black Hills-Northeastern Crook-
736 AM MDT Wed Jul 18 2018

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

.DAY ONE...Today and Tonight

Isolated showers and thunderstorms are possible this afternoon.
Severe weather is not expected at this time. Locally heavy
rainfall will be possible in any thunderstorms.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday

No hazardous weather is expected at this time.

.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

SDZ041-WYZ054>056-058-191315-
Fall River-Northern Campbell-Southern Campbell-Western Crook-
Weston-
736 AM MDT Wed Jul 18 2018

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

.DAY ONE...Today and Tonight

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday

No hazardous weather is expected at this time.

.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, Jul 18, 9:00 AM MST, 4 hours 48 minutes before

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Local storm report, Jul 18, 10:50 AM MST, 2 hours 58 minutes before

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Local storm report, Jul 18, 10:52 AM MST, 2 hours 56 minutes before

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Special weather statement, Jul 18, 1:39 PM MST, 9 minutes before

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The radar

The Rapid City radar (KUDX), 31 km away, was scanning. The volume nearest the first event began at 20:46 UTC.

Open the radar archive at this moment

Event by event

5 thunderstorm wind, 4 hail. Local standard time, as filed.

Thunderstorm Wind, Pennington

When: July 18, 1:48 PM MST
Where: Pennington County, 1 mi ESE of Rapid City
Measured: 52 kt (60 mph) estimated gust
Reported by: Official NWS Observations
Coordinates: 44.075, -103.211

Wind gusts were estimated at 60 mph.

Hail, Pennington

When: July 18, 1:48 PM MST to 1:53 PM MST
Where: Pennington County, Box Elder
Measured: 2 in hail
Reported by: Public
Coordinates: 44.120, -103.070

Hail, Pennington

When: July 18, 1:52 PM MST
Where: Pennington County, 5 mi E of Rapid City
Measured: 1 in hail
Reported by: NWS Employee
Coordinates: 44.080, -103.129

Thunderstorm Wind, Pennington

When: July 18, 1:52 PM MST
Where: Pennington County, 5 mi E of Rapid City
Measured: 52 kt (60 mph) estimated gust
Reported by: NWS Employee
Coordinates: 44.080, -103.129

Wind gusts were estimated at 60 mph.

Thunderstorm Wind, Pennington

When: July 18, 1:53 PM MST
Where: Pennington County, (Rap)rapid City Arpt
Measured: 61 kt (70 mph) measured gust
Reported by: ASOS
Coordinates: 44.050, -103.050

Hail, Pennington

When: July 18, 2:13 PM MST
Where: Pennington County, 2 mi SE of Farmingdale
Measured: 1.25 in hail
Reported by: Trained Spotter
Coordinates: 43.950, -102.852

Hail, Custer

When: July 18, 2:25 PM MST
Where: Custer County, 4 mi SE of Folsom
Measured: 1 in hail
Reported by: Trained Spotter
Coordinates: 43.779, -102.813

Thunderstorm Wind, Custer

When: July 18, 2:25 PM MST
Where: Custer County, 4 mi SE of Folsom
Measured: 52 kt (60 mph) estimated gust
Reported by: Trained Spotter
Coordinates: 43.779, -102.813

Large tree branches were broken by the wind.

Thunderstorm Wind, Oglala Lakota

When: July 18, 2:58 PM MST
Where: Oglala Lakota County, 1 mi NNE of Rockyford
Measured: 52 kt (60 mph) estimated gust
Reported by: Trained Spotter
Coordinates: 43.513, -102.492

Wind gusts were estimated at 60 mph.

What these are

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.
Hail: Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.

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, July 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 2026-10-01. Each event’s entry at NCEI: 765355, 765356, 765357, 765358, 765359, 765362, 765360, 765361, 765363.