A few severe thunderstorms developed during the mid afternoon hours of August 25. A landspout was witnessed by law enforcement briefly touching down in a field southwest of Geneseo, IL around 3:40 PM CDT.
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 DVN wrote it up.
A few severe thunderstorms developed during the mid afternoon hours of August 25. A landspout was witnessed by law enforcement briefly touching down in a field southwest of Geneseo, IL around 3:40 PM CDT. Further to the south, a severe thunderstorm produced large hail and damaging winds. Hail at least golf ball sized was reported and severe wind gusts around 60 MPH resulted in damage to tree limbs, power lines, and shingles. Another separate short lived tornado occurred in Warren County, just east of the town of Berwick, IL.
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 Quad Cities, IA wrote its last area forecast discussion before the first event at Aug 25, 2:11 PM CST, 28 minutes earlier.
Area Forecast Discussion National Weather Service Quad Cities IA IL 311 PM CDT Wed Aug 25 2021 .SYNOPSIS... Issued at 309 PM CDT Wed Aug 25 2021 The latest sfc analysis was indicating a quasi-stationary boundary undulating from acrs southwest IA into the northeastern CWA with a weak wave on it. Other outflow boundaries were located further south acrs KS into northeast MO and into southeast IL. Water vapor imagery and even the VIS loop were indicating a mesoscale convective vort max(MCV) almost overhead. With convective temps generally in the mid 90s, EML, marginal mid level lapse rates and shear, just some isolated high based showers or storms expected through evening being supported by the vort aloft. With the thinning of the cloud debris, have issued a Special Wx Statement for areas south of I80 that may be tickling heat indices near 100. && .SHORT TERM...(This Evening through Thursday) ISSUED AT 309 PM CDT Wed Aug 25 2021 Tonight...After the evening chances for an isolated shower/storm, as the vort pulls away for short wave upper ridging and signs of an unimpressive low level jet(LLJ) or focus, much of the night may be mainly dry. May be rogue and trend down POPs to nil through Thu morning. Won't mention it now, but a low chance for patchy fog in light/variable sfc wind regime if skies clear especially in this morning heavy rain areas. Lows in the upper 60s to low 70s look on track, more low or even mid 70s in some areas with no rain-cooled outflow to worry about if storms don't form overnight. Thursday...Again, maybe a mainly dry morning with ongoing cap and no trigger yet. But the possible trigger looms as a H5 MB short wave kink is expected to be riding the broad thermal ridge over the mid/upper MO RVR VAlley around 12z. This feature will look to develop a type of elevated MCS in that region, with it then tracking east battling the EML and having thoughts of trying to feed southeast and become sfc rooted using cold pool mechanics. If we stay mainly cloud free or have little debris out of Wed night, CAPEs locally could pool into the 3-5K J/kg range again with highs in the low to mid 90s and mid to upper 70 sfc DPTs. Thus setting up a scenario with a storm complex bowing down into the local area with damaging winds, much like what occurred yesterday(Tuesday the 24th). Timing and the extent it makes it south still very uncertain, with a few models keeping it at bay to the north/northwest allowing the EML to win out locally. But several solutions clock us with a severe MCS, thus the slight risk adjustment by SPC. Will increase POPs from the northwest by late afternoon, but interesting some of the latest CAM runs don't have it getting into the northwestern CWA until after 23z or 00z Friday. But they remain not trustworthy and could be too slow. If the debris clouds or mid level ACCAS don't materialize for the first part of the day, a Heat Advisory may need to be hoisted for much of the CWA or at least areas along and south of I80 where indices reach 100+. .LONG TERM...(Thursday Night through next Wednesday) ISSUED AT 309 PM CDT Wed Aug 25 2021 Assessment...medium confidence Unfortunately the models are mixed in their solutions regarding what will occur. Looking under the hood there are hints of an organized thunderstorm complex moving through the area Thursday evening. The internal signal right now says the northern half of the area is most at risk for storms, some of which may be severe. The evening hours would be favored for any severe storms with the primary risk being damaging winds. Given the high moisture levels in the atmosphere there is an additional risk of very heavy rainfall. If storms repeat over the same areas then excessive rainfall would occur with potential flash flooding. Currently the flash flood risk appears very localized so no headline will be issued at this time. Boundaries created by the evening storms will dictate how storms develop/evolve late Thursday night and into Friday. Again the northern half of the area is most favored for additional storms with heavy rainfall a good possibility. These storms will likely carry over into Friday morning before dissipating. Cloud cover and boundaries from the overnight storms will dictate diurnal storm development Friday afternoon. Right now it appears that isolated storms are possible. Friday night/Saturday Assessment...low to medium confidence on rain. Medium to high confidence on high heat. Any diurnal storms that develop Friday afternoon should dissipate with sunset Friday night. However with a boundary in place nocturnal storm development is possible north of I-80 that may persist through sunrise Saturday. Cloud cover Saturday will dictate the overall temperatures. The models keep a boundary in place which will allow moisture to pool during the day which may overcome any lower temperatures in terms of heat index. Right now there appears to be a good possibility of heat index reading reaching or exceeding 100 degrees Saturday afternoon. Right now it appears the atmosphere aloft will be too warm to initiate diurnal convection Saturday afternoon. However a rogue thunderstorm cannot be ruled out. Regardless, 99 percent of the area will likely remain dry. Saturday night/Sunday Assessment...medium confidence The models indicate another cold front will approach and move through the area. Right now the model consensus has chance pops for Saturday night and Sunday during the passage of the front. These pops may increase over the next several days. Sunday night Assessment...medium confidence The models indicate the cold front will finish moving through the area and slowly dissipate with time. Although the forcing weakens along the front it may be enough to allow showers and thunderstorms to persist. Right now the model consensus has slight chance to chance pops for the area. Monday through Wednesday Assessment...high confidence on less humid conditions. Low confidence on rain chances. Less humid conditions will be seen Monday through Wednesday across the area but temperatures will continue to average above normal. The models show some weak upper level disturbances moving through the area which in combination with daytime heating 'may' allow diurnal showers and thunderstorms to develop. Even if this occurs, much of the area is expected to remain dry. Right now the model consensus has slight chance pops Monday through Wednesday. The exception is late Monday night into Tuesday when the model consensus has chance pops. && .AVIATION...(For the 18Z TAFS through 18Z Thursday Afternoon) ISSUED AT 1255 PM CDT Wed Aug 25 2021 Besides some possible MVFR fog before sunrise, will advertise a mainly VFR TAF with light sfc wind regime. Just mid and high level debris clouds. There is a chance for isolated storms to develop in the VCNTY of BRL late this afternoon and evening, and a possible larger complex of storms moving in from the west and northwest late tonight and Thursday morning, but with high uncertainty on these chances will keep mention out of the TAFs thru 18z anyway for now. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && SYNOPSIS...12 SHORT TERM...12 LONG TERM...08 AVIATION...12
Hazardous Weather Outlook National Weather Service Quad Cities IA IL 325 PM CDT Wed Aug 25 2021 IAZ040>042-051>054-063>068-076>078-087>089-098-099-ILZ001-002-007- 009-015>018-024>026-034-035-MOZ009-010-262030- Buchanan-Delaware-Dubuque-Benton-Linn-Jones-Jackson-Iowa-Johnson- Cedar-Clinton-Muscatine-Scott-Keokuk-Washington-Louisa-Jefferson- Henry IA-Des Moines-Van Buren-Lee-Jo Daviess-Stephenson-Carroll- Whiteside-Rock Island-Henry IL-Bureau-Putnam-Mercer-Henderson- Warren-Hancock-McDonough-Scotland-Clark- 325 PM CDT Wed Aug 25 2021 This Hazardous Weather Outlook is for portions of north central Illinois...northwest Illinois...west central Illinois...east central Iowa...northeast Iowa...southeast Iowa and northeast Missouri. .DAY ONE...THIS AFTERNOON AND TONIGHT Isolated thunderstorms can be expected with locally heavy rainfall possible. There is a marginal or level one risk of severe storms. The primary risks are damaging winds and large hail. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY Thunderstorms are forecast for Thursday and especially Thursday night. There is a slight risk or level two risk of severe storms, especially late Thursday afternoon and night. The primary risks are damaging winds and large hail. Additionally there is a risk of excessive rainfall. Right now the area most at risk is north of Interstate 80. Thunderstorms are possible Friday through Wednesday. No severe storms are expected Friday. Beyond Friday it is too early to determine a severe risk. Heat index readings near or exceeding 100 degrees are possible Friday and Saturday, if enough sunshine occurs. .SPOTTER INFORMATION STATEMENT... Spotter activation may be needed late this afternoon and evening. Spotter activation is possible Thursday afternoon and evening.
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
1101 AM CDT WED AUG 25 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0300 PM TSTM WND DMG 1 ENE PENROSE 41.89N 89.65W
08/23/2021 WHITESIDE IL NEWSPAPER
DELAYED REPORT. DAMAGE TO OUTBUILDING, CROP
DAMAGE, LEANING POWER POLES AND DAMAGE TO
TRAILER. RELAYED BY STERLING AND DIXON
TELEGRAPH PHOTOGRAPHER AND REPORTER. TIME
ESTIMATED FROM RADAR.
&&PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
1134 AM CDT WED AUG 25 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0530 AM HEAVY RAIN 2 SE RIVERSIDE 41.46N 91.55W
08/25/2021 M2.25 INCH WASHINGTON IA PUBLIC
0920 AM HEAVY RAIN WASHINGTON 41.30N 91.69W
08/25/2021 M2.38 INCH WASHINGTON IA PUBLIC
0958 AM HEAVY RAIN 2 WSW DOWNEY 41.61N 91.39W
08/25/2021 M1.50 INCH JOHNSON IA TRAINED SPOTTER
RAINFALL IN PAST 24 HOURS.
0740 AM HEAVY RAIN PARNELL 41.58N 92.01W
08/25/2021 M3.20 INCH IOWA IA TRAINED SPOTTER
RAINFALL THIS MORNING - STILL RAINING AND
LOTS OF STANDING WATER.
0752 AM FLASH FLOOD PARNELL 41.59N 92.01W
08/25/2021 IOWA IA PUBLIC
NON-SPECIFIC REPORT FROM MPING FOR
RIVER/CREEK OVERFLOWING; OR CROPLAND OR YARD
OR BASEMENT FLOODING.
0755 AM FLASH FLOOD PARNELL 41.58N 92.00W
08/25/2021 IOWA IA BROADCAST MEDIA
LOTS OF STANDING WATER. ONE LOW LYING STREET
FLOODED.
0759 AM HEAVY RAIN 1 ESE WILLIAMSBURG 41.66N 92.00W
08/25/2021 M3.45 INCH IOWA IA CO-OP OBSERVER
STILL RAINING.
0840 AM HEAVY RAIN 1 ENE NORTH ENGLISH 41.52N 92.06W
08/25/2021 M3.08 INCH IOWA IA CO-OP OBSERVER
&&PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
1151 AM CDT WED AUG 25 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1145 AM HEAVY RAIN 1 NNE OAKDALE 41.71N 91.59W
08/25/2021 M1.40 INCH JOHNSON IA TRAINED SPOTTER
24 HOUR TOTAL.
&&
TASPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
156 PM CDT WED AUG 25 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0155 PM HEAVY RAIN 3 NNE CEDAR RAPIDS 42.01N 91.66W
08/25/2021 M1.82 INCH LINN IA TRAINED SPOTTER
24 HOUR TOTAL.
&&Special Weather Statement National Weather Service Quad Cities IA IL 219 PM CDT Wed Aug 25 2021 IAZ067-068-076>078-087>089-098-099-ILZ015>018-024>026-034-035- MOZ009-010-260000- Muscatine-Scott-Keokuk-Washington-Louisa-Jefferson-Henry IA- Des Moines-Van Buren-Lee-Rock Island-Henry IL-Bureau-Putnam- Mercer-Henderson-Warren-Hancock-McDonough-Scotland-Clark- Including the cities of Muscatine, Davenport, Bettendorf, Sigourney, Washington, Wapello, Fairfield, Mount Pleasant, Burlington, Keosauqua, Fort Madison, Moline, Rock Island, Geneseo, Princeton, Hennepin, Aledo, Oquawka, Monmouth, Carthage, Macomb, Memphis, and Kahoka 219 PM CDT Wed Aug 25 2021 ...Hot and Humid Conditions Through Early Evening... Temperatures in the upper 80s to around 90, combined with an humid air mass, will lead to peak heat indices in the upper 90s to low 100s through 7 PM. Isolated thunderstorms will be possible through early evening as well, and may bring localized relief from the hot temperatures. Take extra precautions if you have to spend time outside. Make sure to drink plenty of fluids and take breaks in the shade. Young children and pets should never be left unattended in vehicles under any circumstances. 12
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE Quad Cities IA/IL
337 PM CDT Wed Aug 25 2021
ILZ015-016-252130-
Rock Island-Henry-
337 PM CDT Wed Aug 25 2021
...Thunderstorms Capable of Producing Funnel Clouds will Affect
eastern Henry County...
At 335 PM CDT...Thunderstorms capable of producing funnel clouds were
along a line from Orio to Woodhull.
LOCATIONS IMPACTED INCLUDE...
Kewanee, Cambridge, Geneseo, Colona, Coal Valley, Galva, Orion,
Atkinson, Annawan, Woodhull, Alpha, Andover, Hooppole, Cleveland,
Warner, Lynn Center, Osborn, Dayton, Osco and Bishop Hill.
Funnel clouds of this nature are short lived and rarely touch the
ground. However, if you notice one approaching the ground, move
indoors to a place of safety.
The National Weather Service will continue to closely monitor the
situation. Please forward reports of funnel cloud sightings to the
nearest law enforcement agency for relay to the National Weather
Service.
LAT...LON 4115 8991 4115 9043 4146 9042 4152 9028
4152 8989
TIME...MOT...LOC 2035Z 180DEG 0KT 4128 9032
SheetsThe Quad Cities radar (KDVN), 39 km away, was scanning. The volume nearest the first event began at 20:41 UTC.
2 tornado, 2 thunderstorm wind, 1 hail. Local standard time, as filed.
Sheriff Sergeant reported a touchdown of a landspout with damage to crops. EM reported a small area with crops damaged in the middle of the field. EF-unknown is the rating.
Numerous tree limbs reported down across the county with powerlines down due to wind. A few houses had shingles blown off.
Estimated wind gust just north of Nakoma.
A trained spotter observed a brief tornado touchdown in a corn field. The tornado path through the corn was about 200 yards long and 30 yards wide. There was no observable damage that could be used to assign a rating for the tornado.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Illinois in 2021Every state in 2021This day in weather historyThe tornado archive for Illinois, 2021Warnings in Illinois, August 2021
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: 975955, 975954, 975959, 975956, 976091.