Thunderstorm Wind, Stephenson
- When
- June 24, 3:07 PM CST
- Where
- Stephenson County, 1.23 mi SW of Rock Grove
- Measured
- 52 kt (60 mph) estimated gust
- Reported by
- Law Enforcement
- Coordinates
- 42.460, -89.520
Power lines blown down in front yard.
The afternoon of June 24th, scattered strong to severe storms developed in southern Wisconsin and Illinois. A few of these storms become supercell thunderstorms, with isolated reports of damaging winds in northwest Illinois.
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.
The afternoon of June 24th, scattered strong to severe storms developed in southern Wisconsin and Illinois. A few of these storms become supercell thunderstorms, with isolated reports of damaging winds in northwest Illinois.
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 Jun 24, 1:26 PM CST, 1 hour 41 minutes earlier. Its key messages:
Area Forecast Discussion National Weather Service Quad Cities IA IL 226 PM CDT Wed Jun 24 2026 .KEY MESSAGES... - Isolated to low end scattered (10-30%) strong to severe storms are possible through sunset. The area at risk is mainly east of the Mississippi and north of I-80. Hail looks to be the primary risk but a localized damaging wind or an isolated tornado cannot be fully ruled out. - A pattern change this weekend will bring heat and humidity to the area. The probability of heat headlines next week has increased to over 50%. && .SHORT TERM /THROUGH THURSDAY/... Issued at 224 PM CDT Wed Jun 24 2026 Satellite through early afternoon shows mainly diurnal cumulus across the area. Better cumulus is located across southwest Wisconsin where lapse rates are steeper and the better radar returns are located. The cool front with a pre-frontal trof will slowly move through the area this afternoon/tonight. CAMs are struggling with the weak forcing but suggest isolated to low end scattered (10-30%) developing along the pre-frontal trof and cold front this afternoon evening. The steep lapse rates and fairly straight hodographs suggest the primary risk this afternoon/evening is hail but a localized damaging wind and isolated tornado cannot be ruled out. Based on progged destabilization, areas mainly east of the Mississippi and north of I-80 are favored for strong to severe storms through sunset. Storms will dissipate with sunset leaving mainly dry conditions overnight, && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... Issued at 224 PM CDT Wed Jun 24 2026 Thursday night through Saturday night Assessment...low to medium (25-40%) confidence on rain Another system will pass mainly south of the area Thursday night into Friday. Some solutions are further north. However, there is a large area ahead of the system with dry easterly flow. Thus there is a reasonably good chance the system will be either; 1) forced further south or 2) have a very sharp northern gradient to any rain. Based on the AIGFS and ECMWF-AIFS and some ML progs, areas north of I-80 look to remain dry Thursday night and Friday. Along and south of I-80 there will be a risk of rain but the better chances still look to be south of an Ottumwa, IA to Galesburg, IL line. Even in this area, rainfall amounts will be around 0.10 inches. Sunday through Wednesday Assessment...a certainty (>95%) of hot and humid conditions The heat and humidity will tease the southwest half of the area on Sunday as dew points rise. The model consensus is probably raising dew points too quickly on Sunday, but, dew points of 65 to 70 are very reasonable. Sunday night through Monday will be dry as the main storm track is well north of the area. Dew points of 70 to 75 are likely to be seen which will push heat indices above 100. The current probability of heat headlines for Monday is over 50 percent now. Monday night into Tuesday the heat and humidity will continue with a 33-40% chance that heat headlines will be needed. However, a system in the Plains will develop a nocturnal storm complex that will track generally east northeast. Data suggests a majority of the area will remain dry as the upper high in the Ohio Valley looks to remain in place through Tuesday. Parts of the far north and northwest have a 20-25% probability of seeing some rain if outflow from the storm complex can initiate some isolated convection. Tuesday night into Wednesday becomes more of a question. The upper high over the Ohio Valley is progged to move closer to the east coast by several solutions. IF correct, this would help weaken the western parts of the heat dome and potentially allow the organized storm track to shift further south. With several solutions indicating a shifting of the upper high toward the east coast, the model consensus does have a southward shift to the organized storm track. The net result is 20-30% rain chances late Tuesday night into Wednesday. PWATS in the model solutions continue to be 1.5 inches or higher. Thus if storms do develop and move across the area, heavy rain can be expected. && .AVIATION /18Z TAFS THROUGH 18Z THURSDAY/... Issued at 1220 PM CDT Wed Jun 24 2026 Cool front progged to move through eastern Iowa and northern Illinois through 12z/25. Stronger winds aloft to allow 10-30% coverage of diurnal convection 20z/24 through 02z/25. Probability of a SHRA/TSRA impacting a TAF site is around 10%. However, if it occurs the impacts could be significant. Thus PROB30 have been included for each TAF site. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...None. IL...None. MO...None. && SHORT TERM...08 LONG TERM...08 AVIATION...08
Hazardous Weather Outlook...UPDATED National Weather Service Quad Cities IA IL 836 AM CDT Wed Jun 24 2026 IAZ040>042-051>054-063>068-076>078-087>089-098-099-ILZ001-002-007- 009-015>018-024>026-034-035-MOZ009-010-251345- 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- 836 AM CDT Wed Jun 24 2026 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...TODAY AND TONIGHT Thunderstorms are expected this afternoon and evening, especially north of Interstate 80. A couple of severe storms are possible with the primary risks being hail and damaging winds. The Storm Prediction Center has a Slight, (level 2 out of 5) risk for severe storms east of the Mississippi and north of Interstate 80. A Marginal (level 1 out of 5) risk for severe storms east of a line from Independence, Iowa to Aledo, Illinois. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY Heat and humidity will overspread the area Sunday through Tuesday. Heat indices of 100 or higher are possible, especially Monday and Tuesday. .SPOTTER INFORMATION STATEMENT... Spotter activation is possible this afternoon and evening.
The Milwaukee radar (KMKX), 97 km away, was scanning. The volume nearest the first event began at 21:08 UTC.
3 thunderstorm wind. Local standard time, as filed.
Power lines blown down in front yard.
A person reported 50 to 60 mph wind gusts with torrential rain.
Large tree branch was blown down. Time estimated from radar.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Illinois in 2026Every state in 2026This day in weather historyWarnings in Illinois, June 2026
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: 1337794, 1337795, 1337796.