Tornadoes and Flash Flooding in South Dakota, July 18 to 19, 2001

Name: Tornadoes and Flash Flooding in South Dakota, July 18 to 19, 2001
Start: 2001-07-18T19:05
End: 2001-07-19T03:57
Location: South Dakota

July 18 to 19, 2001 · NWS ABR · 24 events in 8 counties and zones

12 hail, 7 thunderstorm wind, 3 tornado, 2 flash flood, as filed by the National Weather Service.

Where it happened

Every event with a place to put it; 2 filed by county or forecast zone are drawn at its center, in a lighter ring. 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: 24

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 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 Aberdeen, SD wrote its last area forecast discussion before the first event at Jul 18, 2:15 PM CST, 4 hours 50 minutes earlier.

Area forecast discussion, Jul 18, 2:15 PM CST, 4 hours 50 minutes before

AREA FORECAST DISCUSSION FOR CENTRAL/NORTHCENTRAL AND NORTHEAST
SOUTH DAKOTA AND WEST CENTRAL MINNESOTA
NATIONAL WEATHER SERVICE ABERDEEN SD
315 PM CDT WED JUL 18 2001

INTERESTING DAY. VERY UNSTABLE AIR IN PLACE OVER THE AREA.  MORNING
SOUNDING SHOWED 5500 J/KG CAPE AND LI OF -12.5C WITH A PRECIPITABLE
WATER OF 1.42.  NOT BAD FOR A MORNING SOUNDING.  LAST EVENINGS
SOUNDING SHOWED CAPES OF 7800 AND -16.  VERY INTERESTING VALUES FOR
THIS PART OF THE COUNTRY.  AFTERNOON HEATING CONTINUES TO DESTABILZE
AIR UNDER FAIRLY STRONG CAP.  LATEST GOES DERIVED PRODUCTS FROM 16Z
CONFIRM VERY HIGH CAPE VALUES AND DECREASING CINH VALUES UNDER 100
J/KG JUST WEST OF ABERDEEN.  STILL HAVE VERY WARM MID LAYER IN PLACE
WITH H7 TEMPERATURE OF +11 ON 12Z SOUNDING AND +12 ON GOES DERIVED
SOUNDING.  THIS WARM MID LAYER WOULD NORMALLY BE ENOUGH TO INHIBIT
CONVECTION IN THIS AREA.  HOWEVER AGREE WITH SPC ON EXISTENCE OF SUB
SYNOPTIC BOUNDARIES CLOSE TO THIS AREA TO FOCUS CONVERGENCE AS WELL
AS SYNOPTIC BOUNDARIES TO THE NORTH AND WEST.  H5 WAVE IS MOVING
OVER EAST CENTRAL PART OF THE STATE THAT WILL ALSO AID DEVELOPMENT.
WITH CAP ERODING WILL MENTION CHANCE OF THUNDERSTORMS...SOME
POSSIBLY SEVERE...IN THE EASTERN HALF OF THE AREA.  EXPECT THE MOST
LIKELY AREA TO BE THE NORTH AND EAST PART OF AREA.  NEXT SIGNIFICANT
CHANCE WILL OCCUR THURSDAY NIGHT AND FRIDAY AS STRENGTHENING H5 WAVE
CLOSES OFF OVER NORTHEAST SOUTH DAKOTA.

.EXTENDED DISCUSSION...
EXTENDED MODELS CONTINUE TO SHOW NO RELIEF IN THE HEAT OR HUMIDITY
THROUGH MUCH OF THE EXTENDED PERIOD AS 500MB RIDGE MOVES LITTLE
THROUGH PERIOD. THEREFORE...BIGGEST ISSUE WILL BE THE CHANCES FOR
CONVECTION. THINK MOST OF THE CONVECTION SATURDAY AND SUNDAY WILL
STAY NORTH OF THE AREA AS AVN MODEL WOULD SUGGEST THAT WE WOULD BE
CAPPED. WEAK FRONTAL BOUNDARY PUSHES THROUGH THE REGION ON MONDAY
WHICH WILL GIVE MUCH OF THE CWA A CHANCE FOR STORMS...THEN HIGH
PRESSURE MOVES IN ON TUESDAY. THE HIGH THEN PUSHES OFF TO THE EAST
ON WEDNESDAY AS MRF DEPICTS ANOTHER LEESIDE TROUGH PUSHING INTO THE
WESTERN PLAINS DURING THE DAY. WITH LITTLE CHANGE IN THE RIDGE
PATTERN ALOFT...WENT SIGNIFICANTLY WARMER THAN MRF/MEX GUIDANCE FOR
HIGHS EACH DAY. LOWS SEEMED A TAD LOW IN THE LATER PERIODS...
THEREFORE WENT AT OR SLIGHTLY ABOVE GUIDANCE VALUES DURING THE
PERIOD.

.ABR...NONE.

KEEFE/ECKBERG

In the hours before

Special weather statement, Jul 18, 1:15 PM CST, 5 hours 50 minutes before

HAZARDOUS WEATHER OUTLOOK...UPDATED-UPGRADED RISK OF SEVERE WEATHER
NATIONAL WEATHER SERVICE ABERDEEN SD
215 PM CDT WED JUL 18 2001

MNZ039-046-SDZ005>008-010-011-017>023-191600-
BIG STONE-BROWN-CLARK-CODINGTON-DAY-DEUEL-EDMUNDS-FAULK-GRANT-
HAMLIN-MARSHALL-MCPHERSON-ROBERTS-SPINK-TRAVERSE-
INCLUDING THE CITIES OF...ABERDEEN...BIG STONE CITY...BRITTON...
CLARK...CLEAR LAKE...ESTELLINE...EUREKA...FAULKTON...GROTON...
IPSWICH...MILBANK...ORTONVILLE...REDFIELD...SISSETON...WATERTOWN...
WEBSTER AND WHEATON
204 PM CDT WED JUL 18 2001

...UPDATED HAZARDOUS WEATHER OUTLOOK THROUGH THURSDAY MORNING...
THE SLIGHT RISK OF SEVERE THUNDERSTORMS HAS BEEN UPGRADED TO A
MODERATE RISK FOR TONIGHT. SCATTERED THUNDERSTORMS ARE EXPECTED TO
DEVELOP OVER NORTHEAST SOUTH DAKOTA THIS EVENING...THEN PUSH INTO
MINNESOTA OVERNIGHT. SOME OF THE STORMS ARE EXPECTED TO BECOME
SEVERE...WITH THE PRIMARY THREAT BEING DAMAGING WINDS AND LARGE
HAIL. HEAVY RAINFALL AND DANGEROUS LIGHTNING WILL ALSO ACCOMPANY
THESE STORMS.

SPOTTER ACTIVATION MAY BE REQUIRED LATE THIS EVENING.

SDZ003-004-009-015-016-033>037-045-048-191600-
CAMPBELL-CORSON-DEWEY-HAND-HUGHES-HYDE-JONES-LYMAN-POTTER-STANLEY-
SULLY-WALWORTH-
INCLUDING THE CITIES OF...FORT PIERRE...GETTYSBURG...HIGHMORE...LOWER
BRULE...MCLAUGHLIN...MILLER...MOBRIDGE...MURDO...ONIDA...PIERRE...
PRESHO AND SELBY
215 PM CDT WED JUL 18 2001

...UPDATED HAZARDOUS WEATHER OUTLOOK THROUGH THURSDAY MORNING...
THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS EVENING ACROSS
NORTH CENTRAL SOUTH DAKOTA. IF THUNDERSTORMS FORM...THERE IS A
CHANCE THAT A FEW OF THE STORMS MAY BECOME SEVERE.

SPOTTER \ACTIVATION MAY BE REQUIRED THIS EVENING.

ECKBERG

The radar

The Aberdeen radar (KABR), 112 km away, was scanning. The volume nearest the first event began at 01:07 UTC.

Open the radar archive at this moment

Event by event

12 hail, 7 thunderstorm wind, 3 tornado, 2 flash flood. Local standard time, as filed.

Hail, Walworth

When: July 18, 7:05 PM CST
Where: Walworth County, 12 mi SE of Selby
Measured: 2.75 in hail
Reported by: GENERAL PUBLIC
Coordinates: 45.383, -99.850

Hail, Edmunds

When: July 18, 7:07 PM CST
Where: Edmunds County, Bowdle
Measured: 0.88 in hail
Reported by: TRAINED SPOTTER
Coordinates: 45.450, -99.667

Tornado, Edmunds

When: July 18, 7:40 PM CST to 7:50 PM CST
Where: Edmunds County, 14 mi S of Bowdle
Rating: F2
Path length: 1 mi
Path width: 100 yd
Reported by: NWS STORM SURVEY
Coordinates: 45.250, -99.667

A tornado touched down and heavily damaged a house. The attached garage was totally destroyed with two vehicles badly damaged. The metal roof was ripped off of the barn with three outbuildings destroyed. Five telephone/power poles were broken off with 1/2 to 3/4 of a mile of power lines down. Also, a small windmill was wrapped around a power pole.

Tornado, McPherson

When: July 18, 7:45 PM CST to 8:00 PM CST
Where: McPherson County, 10 mi N of Eureka
Rating: F0
Path length: 0.5 mi
Path width: 50 yd
Reported by: NWS STORM SURVEY
Coordinates: 45.917, -99.633

A tornado touched down north of Eureka. The tornado remained in open country and caused no damage. Path length and width were estimated.

Hail, Potter

When: July 18, 8:03 PM CST
Where: Potter County, 2 mi NE of Tolstoy
Measured: 2.75 in hail
Reported by: GENERAL PUBLIC
Coordinates: 45.217, -99.600

Hail, Edmunds

When: July 18, 8:15 PM CST
Where: Edmunds County, 13 mi NW of Loyalton
Measured: 1 in hail
Reported by: TRAINED SPOTTER
Coordinates: 45.417, -99.467

Hail, Potter

When: July 18, 8:15 PM CST
Where: Potter County, 3 mi NE of Tolstoy
Measured: 1.75 in hail
Reported by: GENERAL PUBLIC
Coordinates: 45.233, -99.583

Tornado, Faulk

When: July 18, 8:19 PM CST to 8:29 PM CST
Where: Faulk County, 5 mi NW of Onaka
Rating: F0
Path length: 0.3 mi
Path width: 25 yd
Reported by: NWS STORM SURVEY
Coordinates: 45.233, -99.550

A tornado touched down northwest of Onaka traveling through a field. The tornado only caused some tree damage. Path length and width were estimated.

Hail, Faulk

When: July 18, 9:07 PM CST
Where: Faulk County, 4 mi W of Onaka
Measured: 0.75 in hail
Reported by: GENERAL PUBLIC
Coordinates: 45.183, -99.567

Hail, Faulk

When: July 18, 9:10 PM CST
Where: Faulk County, 3 mi N of Onaka
Measured: 0.75 in hail
Reported by: TRAINED SPOTTER
Coordinates: 45.233, -99.483

Hail, Edmunds

When: July 18, 9:10 PM CST
Where: Edmunds County, 9 mi SW of Loyalton
Measured: 0.75 in hail
Reported by: EMERGENCY MANAGER
Coordinates: 45.183, -99.417

Hail, Edmunds

When: July 18, 9:30 PM CST
Where: Edmunds County, 13 mi S of Bowdle
Measured: 1 in hail
Reported by: TRAINED SPOTTER
Coordinates: 45.267, -99.667

Flash Flood, Faulk

When: July 18, 9:30 PM CST to July 19, 12:15 AM CST
Where: Faulk County, Northwest Portion
Reported by: LAW ENFORCEMENT
Coordinates: 45.071, -99.145 (the zone’s center; the record gives no point)

Very heavy rains of 3 to 4 inches fell across northwest Faulk and southwest Edmunds flooding several roads and streams.

Flash Flood, Edmunds

When: July 18, 9:30 PM CST to July 19, 12:15 AM CST
Where: Edmunds County, Southwest Portion
Reported by: LAW ENFORCEMENT
Coordinates: 45.419, -99.215 (the zone’s center; the record gives no point)

Thunderstorm Wind, Corson

When: July 18, 11:20 PM CST
Where: Corson County, Keldron
Measured: 52 kt (60 mph)
Reported by: LAW ENFORCEMENT
Coordinates: 45.933, -101.817

Thunderstorm Wind, Corson

When: July 19, 12:07 AM CST
Where: Corson County, 1 mi SW of Mc Intosh
Measured: 65 kt (75 mph)
Reported by: TRAINED SPOTTER
Coordinates: 45.900, -101.367

Thunderstorm Wind, Corson

When: July 19, 12:07 AM CST
Where: Corson County, 3 mi SW of Mc Intosh
Measured: 50 kt (58 mph)
Reported by: LAW ENFORCEMENT
Coordinates: 45.883, -101.400

Hail, Corson

When: July 19, 12:07 AM CST
Where: Corson County, 3 mi SW of Mc Intosh
Measured: 1 in hail
Reported by: LAW ENFORCEMENT
Coordinates: 45.883, -101.400

Thunderstorm Wind, Corson

When: July 19, 12:25 AM CST
Where: Corson County, 2 mi W of Mc Laughlin
Measured: 61 kt (70 mph)
Reported by: LAW ENFORCEMENT
Coordinates: 45.817, -100.850

Winds to 70 mph along with quarter size hail broke many windows on the west side of buildings in McLaughlin. Alot of siding was also damaged along with shingles. Many vehicles were also dented along with some windshields broken out.

Hail, Corson

When: July 19, 12:25 AM CST
Where: Corson County, 2 mi W of Mc Laughlin
Measured: 1 in hail
Reported by: LAW ENFORCEMENT
Coordinates: 45.817, -100.850

Thunderstorm Wind, Campbell

When: July 19, 12:50 AM CST
Where: Campbell County, 9 mi W of Mound City
Measured: 52 kt (60 mph)
Reported by: LAW ENFORCEMENT
Coordinates: 45.717, -100.250

Thunderstorm Wind, Campbell

When: July 19, 1:30 AM CST
Where: Campbell County, 10 mi NE of Mound City
Measured: 52 kt (60 mph)
Reported by: LAW ENFORCEMENT
Coordinates: 45.817, -99.917

Thunderstorm Wind, McPherson

When: July 19, 2:35 AM CST
Where: McPherson County, 7 mi E of Leola
Measured: 56 kt (64 mph)
Reported by: TRAINED SPOTTER
Coordinates: 45.717, -98.800

Hail, Spink

When: July 19, 3:57 AM CST
Where: Spink County, Redfield
Measured: 1 in hail
Reported by: LAW ENFORCEMENT
Coordinates: 44.867, -98.517

What these are

Hail: Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.
Tornado: A violently rotating column of air in contact with the ground and extending from a thunderstorm, filed with its path, width and Fujita or Enhanced Fujita rating from the damage survey.
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.
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.

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

The same day elsewhere

Every storm in South Dakota in 2001 Every state in 2001 This day in weather history The tornado archive for South Dakota, 2001 Warnings in South Dakota, July 2001

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 2026-09-24. Each event’s entry at NCEI: 5261384, 5261385, 5261468, 5261388, 5261453, 5261454, 5261455, 5261452, 5261457, 5261386, 5261458, 5261456, 5261469, 5261470, 5261459, 5261387, 5261461, 5261462, 5261465, 5261466, 5261460, 5261463, 5261464, 5261467.