A weak area of low pressure tracking along a nearly stationary frontal boundary triggered scattered thunderstorms during the late afternoon and evening of August 21st. One cell produced a brief EF-0 tornado southwest of Decatur in Macon County.
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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 ILX wrote it up.
A weak area of low pressure tracking along a nearly stationary frontal boundary triggered scattered thunderstorms during the late afternoon and evening of August 21st. One cell produced a brief EF-0 tornado southwest of Decatur in Macon 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 Lincoln, IL wrote its last area forecast discussion before the first event at Aug 21, 5:38 PM CST, 1 hour 21 minutes earlier.
Area Forecast Discussion National Weather Service Lincoln IL 638 PM CDT Wed Aug 21 2019 .SYNOPSIS... Issued at 340 PM CDT Wed Aug 21 2019 The threat of showers and some thunderstorms will persist across central and southeast Illinois through Thursday night. The best chances will be along and south of I-72, where around 1 to 1.5 inches of rain is possible by dawn Friday. A chance of showers and thunderstorms will linger in southeast IL on Friday before the frontal boundary pushes further south of the area. Warm and humid conditions again this afternoon will transition to cooler and less humid conditions during the next few days. && .SHORT TERM...(This evening through Thursday) ISSUED AT 340 PM CDT Wed Aug 21 2019 Remnants of an MCS that moved into central IL this afternoon, produced an outflow boundary that was pushing se toward I-70 at mid afternoon. A few mainly light rain showers were over the IL river valley behind this boundary with some thunderstorms over ne IL tracking ENE toward Chicago metro. A band of thunderstorms extended from near Evansville IN into southeast MO and nw AR, more numerous over the Ozarks. LAPS capes were 2000-3200 j/kg over eastern/se IL, while higher capes over 3500 j/kg were over sw IL into southern MO with better support of stronger thunderstorms sw of our CWA. Also have an MCV near the IA/MO border with scattered convection over parts of IA into nw MO. Mostly cloudy to overcast skies prevailed over central IL with partly sunny skies in southeast IL. Expect convection chances to increase into tonight across the CWA as outflow boundary moving into southeast IL could develop some late day convection, and also the MCV moving east from IA and northern MO to increase coverage of convection over northern CWA too going into tonight. SPC day1 update continues a marginal risk of severe storms over southern half of CWA into this evening for mainly gusty winds. Also have marginal to slight risk of excessive rainfall thru tonight, highest chances (slight chance) in southeast IL. Lows overnight mostly in the mid to upper 60s, but range from lower 60s nw of Peoria to near 70F in southeast IL. Best chances of convection to shift into southern CWA on Thu as frontal boundary slowly moves southward into southern/se IL while marginal risk of severe storms shifts just south of CWA on Thu. WPC has a marginal risk of excessive rainfall over southeast IL mainly south of I-70 on Thu. Highs Thu in the upper 70s to near 80F in central IL and lower 80s south of I-70. .LONG TERM...(Thursday night through Wednesday) ISSUED AT 340 PM CDT Wed Aug 21 2019 Convection chances linger over southern CWA especially southeast IL Thu night into Friday as a weak surface low tracks along the boundary to our south into the mid MS river valley overnight Thu night. Meanwhile northern CWA starts drying out. Lows Thu night range from upper 50s to around 60F northern CWA and mid 60s se of I-70. Highs Friday in the upper 70s in central IL and around 80F in southeast IL, with less humid conditions especially in central IL. Lingering small chances of showers and isolated thunderstorms in far southeast IL Friday night into Saturday, while brunt of CWA should be dry with frontal boundary getting further south. Highs Saturday again in the upper 70s to near 80F and less humid air pushing into southeast IL too by Saturday. Saturday night into Sunday appears dry over much of CWA, then slight chance of convection in southeast IL on Sunday afternoon due to weak instability toward the Ohio river valley. Lows Sat night in the upper 50s to near 60F, highs Sunday in the upper 70s to near 80F. Dry wx expected across area on Sunday night with lows of 60-65F. Extended models show a large mid/upper level northern stream trof digging into the Midwest by Monday and across the Great Lakes region by Tue and digging further into the area by next Wed. A frontal boundary to push se into the area early next work week, though some timing differences between models with this feature. Stayed close to consensus from Monday on. This could return a chance of showers and a few thunderstorms Monday into Wed over the area. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 630 PM CDT Wed Aug 21 2019 A few widely scattered showers and thunderstorms are possible across central Illinois this evening and tonight, but expect coverage to remain fairly low so will only include a VCSH in the forecast for now. Precip chances will shift east overnight, then attention will turn to fog and stratus development. For now the best chances for fog appear along the I-72 corridor terminals where a surface boundary is lingering and dew point remain in the low to mid 70s. There is another slight chance for showers and storms on Thursday, but it appears the focus will shift south of the terminals towards the I-70 corridor. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && SYNOPSIS...07 SHORT TERM...07 LONG TERM...07 AVIATION...Deubelbeiss
Hazardous Weather Outlook National Weather Service Lincoln IL 322 PM CDT Wed Aug 21 2019 ILZ027>031-036>038-041>046-221100- Champaign-De Witt-Fulton-Knox-Logan-Marshall-Mason-McLean-Peoria- Piatt-Stark-Tazewell-Vermilion-Woodford- 322 PM CDT Wed Aug 21 2019 This Hazardous Weather Outlook is for portions of central Illinois, east central Illinois and west central Illinois. .DAY ONE...TONIGHT... Scattered thunderstorms will be possible through tonight: however, severe weather is not expected. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY... Thunderstorm chances will linger across the area Thursday and Thursday night. The potential for severe weather appears low. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed through tonight. ILZ040-047>057-061>063-066>068-071>073-221100- Cass-Christian-Clark-Clay-Coles-Crawford-Cumberland-Douglas-Edgar- Effingham-Jasper-Lawrence-Macon-Menard-Morgan-Moultrie-Richland- Sangamon-Schuyler-Scott-Shelby- 322 PM CDT Wed Aug 21 2019 This Hazardous Weather Outlook is for portions of central Illinois, east central Illinois, southeast Illinois and west central Illinois. .DAY ONE...TONIGHT... Scattered thunderstorms will be possible through tonight. There is a Marginal Risk that some of the storms may produce damaging wind gusts to 60 mph. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY... Thunderstorm chances will linger across the area Thursday through Friday. The potential for severe weather appears low both days. .SPOTTER INFORMATION STATEMENT... Spotter activation may be needed through 8 pm.
The Lincoln radar (KILX), 46 km away, was scanning. The volume nearest the first event began at 00:58 UTC.
1 tornado. Local standard time, as filed.
A tornado touched down 3.5 miles southwest of Decatur just southeast of the Rock Springs Conservation Area at 7:59 PM CDT. The tornado tracked eastward damaging a few tree branches, then quickly dissipated one minute later at 8:00 PM CDT.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Illinois in 2019Every state in 2019This day in weather historyThe tornado archive for Illinois, 2019Warnings in Illinois, August 2019
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: 853726.