Hail, Tripp
- When
- August 4, 5:18 PM CST
- Where
- Tripp County, 5 mi N of Witten
- Measured
- 2 in hail
- Reported by
- Public
- Coordinates
- 43.502, -100.080
Tornadoes and Hail in South Dakota, August 4, 2020
A thunderstorm became severe as it moved into Tripp County. The storm produced large hail, strong wind gusts, and two tornadoes.
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
The toll
- Deaths
- 0
- Injuries
- 0
- Property damage
- None recorded
- Crop damage
- None recorded
- Events
- 5
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 thunderstorm became severe as it moved into Tripp County. The storm produced large hail, strong wind gusts, and two tornadoes.
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 Aug 4, 4:55 PM CST, 23 minutes earlier.
Area forecast discussion, Aug 4, 4:55 PM CST, 23 minutes before
Area Forecast Discussion For Western SD and Northeastern WY National Weather Service Rapid City SD 455 PM MDT Tue Aug 4 2020 .DISCUSSION...(This Evening Through Tuesday) Issued at 119 PM MDT Tue Aug 4 2020 Upper level analysis shows compact shortwave pushing eastward across southern Saskatchewan with trough axis extending southward into the northern plains. Surface trough axis extends from developing low pressure across NE Colorado this afternoon. Modest MUCAPE (1000-2500 J/kg) will be in place this afternoon and evening, although shear will be marginal. Broad upper level ascent via shortwave trough coupled with convergent flow along the southern Black Hills will provide impetus for thunderstorm development. The overall environment will be conducive to a few strong to severe storms through the evening before tapering off later tonight. Widespread severe weather is not anticipated this evening. Northwest flow continues Wednesday with chances for a storm or two through the day Wednesday, mainly across SW SD, although the best chances will remain to our northeast and south of the forecast area. Mid-level warm air advection spreads into the northern Plains overnight Wednesday as upper level ridge builds Thursday into Friday. Temperatures will warm back into the upper 80s to 90s for most locations to end the week. Southwesterly flow aloft becomes the dominant pattern moving into the weekend with embedded waves rippling through the flow. While the best upper level forcing will remain well off to the north, orographic forcing coupled with subtle waves will likely be enough to support at least a small chance of thunderstorms each day Thursday through the weekend. A thermal ridge will be in place across the region Thursday into Friday, with warm air aloft and subsequent capping concerns likely limiting more widespread storms. Additionally, bulk shear looks rather weak through Saturday (20 to 35 knots), further limiting overall severe potential. At this point, greatest likelihood for showers and storms looks to remain across south-central into eastern SD each day where higher quality boundary layer moisture will be in place. Westerly to southwesterly flow will continue through the weekend into next week with temperatures near normal and generally dry conditions expected. Dry westerly flow will likely result in elevated fire weather concerns beginning this weekend. At this point winds look to remain below criteria, however minimum daily RH values will likely fall into the teens, particularly across SW SD and NE WY this weekend into early next week. && .AVIATION...(For the 00Z TAFS Through 00Z Wednesday Evening) Issued At 453 PM MDT Tue Aug 4 2020 Isolated thunderstorms over northwest SD, as well as south central SD, will dissipate this evening. Brief MVFR/IFR conditions in stronger storms. Outside of storms, VFR conditions expected through the period. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...None. WY...None. && DISCUSSION...Eagan AVIATION...Johnson
Hazardous weather outlook, Aug 4, 11:43 AM CST, 5 hours 35 minutes before
Hazardous Weather Outlook...UPDATED National Weather Service Rapid City SD 1143 AM MDT Tue Aug 4 2020 SDZ001-002-012>014-024>032-041>044-046-047-049-072>074-051300- Harding-Perkins-Butte-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-Pennington Co Plains-Haakon-Fall River- Oglala Lakota-Jackson-Bennett-Mellette-Todd-Tripp- Sturgis/Piedmont Foot Hills-Southern Meade Co Plains- Hermosa Foot Hills- 1143 AM MDT Tue Aug 4 2020 /1243 PM CDT Tue Aug 4 2020/ This Hazardous Weather Outlook is for all of western and south central South Dakota. .DAY ONE...This Afternoon and Tonight Isolated severe thunderstorms with large hail and strong wind gusts are possible this afternoon and early evening. .DAYS TWO THROUGH SEVEN...Wednesday through Monday Thunderstorms are possible through the weekend but widespread severe weather is not expected. .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 WYZ054>058-071-051300- Northern Campbell-Southern Campbell-Western Crook- Wyoming Black Hills-Weston-Northeastern Crook- 1143 AM MDT Tue Aug 4 2020 This Hazardous Weather Outlook is for northeastern Wyoming and the Black Hills of Wyoming. .DAY ONE...This Afternoon and Tonight Isolated thunderstorms are possible this afternoon but are not expect to become severe. .DAYS TWO THROUGH SEVEN...Wednesday through Monday Thunderstorms are possible through the weekend but widespread severe weather is not expected. .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
The radar
The North Platte radar (KLNX), 176 km away, was scanning. The volume nearest the first event began at 23:16 UTC.
Event by event
2 hail, 2 tornado, 1 thunderstorm wind. Local standard time, as filed.
Tornado, Tripp
- When
- August 4, 5:29 PM CST to 5:33 PM CST
- Where
- Tripp County, 3 mi N of Witten
- Rating
- EF0
- Path length
- 0.02 mi
- Path width
- 10 yd
- Reported by
- Public
- Coordinates
- 43.473, -100.080
A brief tornado touched down in an open area, causing no damage.
Tornado, Tripp
- When
- August 4, 5:39 PM CST to 5:41 PM CST
- Where
- Tripp County, 4 mi SW of Winner
- Rating
- EF0
- Path length
- 0.02 mi
- Path width
- 10 yd
- Reported by
- Public
- Coordinates
- 43.329, -99.926
A brief tornado touched down in an open area, causing no damage.
Hail, Tripp
- When
- August 4, 6:30 PM CST
- Where
- Tripp County, 3.14 mi ENE of Wewela
- Measured
- 1 in hail
- Reported by
- Public
- Coordinates
- 43.028, -99.723
Thunderstorm Wind, Tripp
- When
- August 4, 6:30 PM CST
- Where
- Tripp County, 4 mi NE of Wewela
- Measured
- 52 kt (60 mph) estimated gust
- Reported by
- Public
- Coordinates
- 43.051, -99.724
Wind gusts were estimated at 60 mph.
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.
- 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
- Tropical Storm in New York, August 4, 2020
- Tornadoes in North Carolina, August 4, 2020
- Tornadoes and Tropical Storm in Pennsylvania, August 4, 2020
- Tornadoes and Tropical Storm in Maryland, August 4 to 5, 2020
- Tropical Storm in Connecticut, August 4, 2020
- Tornadoes in Virginia, August 4, 2020
- Tropical Storm and Astronomical Low Tide in New Hampshire, August 4 to 5, 2020
- Tornadoes in Maryland, August 4, 2020
- Tropical Storm in Connecticut, August 4, 2020
- Tropical Storm in North Carolina, August 4, 2020
- Tropical Storm in Virginia, August 4, 2020
- Tornadoes and Tropical Storm in Delaware, August 4, 2020
More
Every storm in South Dakota in 2020Every state in 2020This day in weather historyThe tornado archive for South Dakota, 2020Warnings in South Dakota, August 2020
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: 912088, 916395, 916396, 912089, 912090.