An intense cluster of severe thunderstorms developed along Interstate 44 from Mount Vernon to far southeast Kansas as a southward moving outflow boundary interacted with a very unstable air mass. The storms produced hail up to the size of tennis balls as they moved southwestward into Cherokee County.
Every event with a place to put it. Tap one for its entry below.
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.
The episode as NWS SGF wrote it up.
An intense cluster of severe thunderstorms developed along Interstate 44 from Mount Vernon to far southeast Kansas as a southward moving outflow boundary interacted with a very unstable air mass. The storms produced hail up to the size of tennis balls as they moved southwestward into Cherokee County.
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 Springfield, MO wrote its last area forecast discussion before the first event at Aug 15, 2:05 PM CST, 1 hour 20 minutes earlier.
Area Forecast Discussion National Weather Service Springfield MO 305 PM CDT Sat Aug 15 2020 .SHORT TERM...(This evening through Sunday) Issued at 242 PM CDT Sat Aug 15 2020 Expecting isolated to perhaps scattered convection near the Arkansas/Missouri border and in the far southwest CWA (far southeast Kansas and far SW Missouri). The convection is in response to an outflow boundary moving S-SW across the area and a cold front currently along the northern CWA border that will continue to move south. Current surface based CAPE is analyzed to be 4,500-5,500 J/kg and shear is very limited ahead of the boundaries. Limited moisture along with the weak shear will keep storms isolated and short lived, but with the instability in place we could see some brief strong to severe storms. Convection will diminish this evening, leaving a pleasant night and day Sunday. Lows tonight will be in the low to mid 60s with Sunday seeing sunny skies and highs in the mid 80s. Not only will Sunday be cooler, but also drier with dew points 15-20 degrees lower than today. .LONG TERM...(Sunday Night through Saturday) Issued at 242 PM CDT Sat Aug 15 2020 Not carrying any precip chances through this period and not seeing any chances for significant precip through the week. High temperatures will be warmest on Monday in the mid 80s to lower 90s, then in the mid to upper 80s the rest of the week. Afternoon dew points will be in the mid 50s to low 60s through the period, making conditions even more comfortable under mostly clear skies. Overnight low temperatures will be in the upper 50s to mid 60s. && .AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon) Issued at 1240 PM CDT Sat Aug 15 2020 A cold front moving through will switch winds to a northerly direction and bring chances for showers and storms later this afternoon and evening. Greatest chances for storms are at KJLN, with chances being too limited elsewhere to include in the forecast at this time. Otherwise, VFR conditions are expected. && .SGF WATCHES/WARNINGS/ADVISORIES... MO...NONE. KS...NONE. && SHORT TERM...Titus LONG TERM...Titus AVIATION...Titus
Hazardous Weather Outlook National Weather Service Springfield MO 204 PM CDT Sat Aug 15 2020 KSZ073-097-101-MOZ055>058-066>071-077>083-088>098-101>106-161915- Bourbon-Crawford-Cherokee-Benton-Morgan-Miller-Maries-Vernon- St. Clair-Hickory-Camden-Pulaski-Phelps-Barton-Cedar-Polk-Dallas- Laclede-Texas-Dent-Jasper-Dade-Greene-Webster-Wright-Newton- Lawrence-Christian-Douglas-Howell-Shannon-McDonald-Barry-Stone- Taney-Ozark-Oregon- 204 PM CDT Sat Aug 15 2020 This Hazardous Weather Outlook is for portions of the Missouri Ozarks and extreme southeast Kansas. .DAY ONE...This Afternoon and Tonight. Weather hazards expected... Limited hail risk. Limited thunderstorm wind damage risk. Limited lightning risk. Limited excessive heat risk. DISCUSSION... A few isolated thunderstorms will be possible along and south of Interstate 44 today, with potential for an isolated strong to severe thunderstorm. Hail to the size of quarters and winds to 60 mph are possible with any isolated severe storms. Most locations will remain dry. Heat index values in the mid 90s to low 100s will continue this afternoon, mainly over southern and western portions of the area. .DAYS TWO THROUGH SEVEN...Sunday through Friday. No hazardous weather is expected at this time. .SPOTTER INFORMATION STATEMENT... Spotter activation is not anticipated through tonight. && More detailed information can be accessed at: http://www.weather.gov/sgf/sitrep This product in graphical format...along with other weather... hydrological and climate information...at http://www.weather.gov/sgf Titus
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SPRINGFIELD MO
1218 PM CDT SAT AUG 15 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0915 AM TSTM WND DMG 3 WNW LOWRY CITY 38.15N 93.78W
08/15/2020 ST. CLAIR MO EMERGENCY MNGR
A TREE FELL ONTO AND DOWNED A FEW POWER
LINES NEAR THE INTERSECTION OF HIGHWAY A AND
CENTER ROAD. TIME ESTIMATED FROM RADAR.
&&
CKRSpecial Weather Statement National Weather Service Springfield MO 340 PM CDT Sat Aug 15 2020 MOZ088-152115- Jasper MO- 340 PM CDT Sat Aug 15 2020 ...SIGNIFICANT WEATHER ADVISORY FOR WESTERN JASPER COUNTY UNTIL 415 PM CDT... At 340 PM CDT, Doppler radar was tracking a strong thunderstorm near Oronogo, or 9 miles north of Joplin, moving southeast at 20 mph. Penny size hail and wind gusts up to 50 mph will be possible with this storm. Locations impacted include... Northern Joplin... Carthage... Webb City... Carl Junction... Oronogo... Carterville... Airport Drive... Alba... Purcell... Asbury... Neck City... Brooklyn Heights... Waco... Oakland Park... This includes Interstate 49 between mile markers 37 and 38. PRECAUTIONARY/PREPAREDNESS ACTIONS... This storm may intensify, so be certain to monitor local radio stations and available television stations for additional information and possible warnings from the National Weather Service. && LAT...LON 3731 9461 3731 9446 3710 9429 3710 9462 TIME...MOT...LOC 2040Z 324DEG 19KT 3723 9451 Rothstein
Special Weather Statement National Weather Service Springfield MO 418 PM CDT Sat Aug 15 2020 MOZ088-093-152145- Jasper MO-Newton MO- 418 PM CDT Sat Aug 15 2020 ...SIGNIFICANT WEATHER ADVISORY FOR NORTHEASTERN NEWTON AND SOUTHEASTERN JASPER COUNTIES UNTIL 445 PM CDT... At 418 PM CDT, Doppler radar was tracking a strong thunderstorm near Diamond, or 9 miles south of Carthage, moving southeast at 25 mph. Nickel size hail and wind gusts up to 50 mph will be possible with this storm. Locations impacted include... Carthage... Granby... Diamond... Fidelity... Reeds... This includes the following highways... Interstate 44 between mile markers 15 and 27. Interstate 49 between mile markers 36 and 40. PRECAUTIONARY/PREPAREDNESS ACTIONS... Monitor the weather situation closely. Listen for possible warnings and be prepared to take appropriate action should severe weather threaten. This storm may intensify, so be certain to monitor local radio stations and available television stations for additional information and possible warnings from the National Weather Service. && LAT...LON 3713 9438 3718 9421 3700 9409 3692 9430 TIME...MOT...LOC 2118Z 335DEG 20KT 3705 9425 DSA
The Springfield radar (KSGF), 108 km away, was scanning. The volume nearest the first event began at 21:24 UTC.
9 hail. Local standard time, as filed.
Hail ranging in size from nickles to golf balls was reported on Highway YY west of Carl Junction at the state line.
Half dollar sized hail was reported.
Half dollar sized hail was reported via social media.
Hail to the size of tennis balls was reported in a rural area northwest of Riverton. No damage was reported.
Quarter sized hail was reported.
A picture of hail to the size of tennis balls was received via social media from a rural part of the county. Minor roof and vehicle damage occurred to the farm stead where the hail occurred.
Hail from half dollar to golf balls in size was reported.
Quarter sized hail was reported.
Hail up to golf balls in size was reported.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Kansas in 2020Every state in 2020This day in weather historyWarnings in Kansas, August 2020
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: 917398, 917399, 917400, 917401, 917402, 917403, 917404, 917405, 917406.