During the afternoon and evening of the 16th, a series of severe thunderstorms produced widespread damaging winds and instances of severe hail around the western and northwestern Chicago metro area.
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 LOT wrote it up.
During the afternoon and evening of the 16th, a series of severe thunderstorms produced widespread damaging winds and instances of severe hail around the western and northwestern Chicago metro area.
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 Chicago, IL wrote its last area forecast discussion before the first event at Aug 16, 2:07 PM CST, 23 minutes earlier. Its key messages:
Area Forecast Discussion
National Weather Service Chicago/Romeoville, IL
307 PM CDT Sat Aug 16 2025
.KEY MESSAGES...
- Strong to damaging-wind producing storms (some also with large
hail) are likely late afternoon through early evening across
the area.
- Additional storms may develop tonight, though the favored zone
is currently just northwest of the area.
- A brief break in the pattern is expected Sunday before hot and
humid conditions, as well as a threat for storms, returns
Monday and Tuesday.
&&
.MESOSCALE...
Issued at 215 PM CDT Sat Aug 16 2025
A cluster of thunderstorms continues to fester across southern
WI this afternoon as a mid-level shortwave interacts with the
humid and unstable air mass. Radar trends over the past few
hours have shown the cluster of storms, especially the storms
near and west of Madison, to be starting to turn more
southeasterly which puts them more on track to move into
portions of northern IL. Additionally, there is an outflow
boundary racing out ahead of the storms which should serve as
the focus for new storm development as it moves southward into
northern IL this afternoon.
Given that the environment across northern IL is somewhat
unstable (MLCAPE around 3500 J/kg) and very humid (dew points in
the low to mid-70s), the outflow should be able to kick off
additional thunderstorms over the next 1-3 hours. The main area
for thunderstorms looks to be favored along and northeast of a
line from Rockford, IL to Rensselaer, IN but scattered storms
could develop outside of this area if sufficient forcing is
realized. From a severe perspective, wind shear overhead is
rather weak around 20-25 kts as of 2 PM but should increase a
bit as the aforementioned shortwave dives towards Lake Michigan
this evening. Therefore, there is a chance for some stronger
storms to materialize and result in winds gusts up to 60-70 mph
as the main threat. It was for this reason that a Severe
Thunderstorm Watch was issued for portions of northeast IL and
northwest IN through 7 PM this evening.
Additional thunderstorms will be possible behind this initial
cluster as a another disturbance moves out of southeast MN
overnight, but confidence on the coverage and severity of this
second wave is low and will depend on what the initial wave
does. Thus we will have provide more updates on this part of the
forecast at a later time.
Yack
&&
.DISCUSSION...
Issued at 307 PM CDT Sat Aug 16 2025
Tonight through Sunday:
Convection is expected to sag southward into central and
southern Illinois later this evening. In its wake, modest
isentropic upglide will persist into tonight atop the residual
cold pool. Accordingly, this may support additional scattered
shower and storms development in our region into tonight.
However, the core of the low-level jet is expected to remain
positioned just northwest of our area, and thus suspect that
must of the substantial renewed development will be somewhere
in the southern Minnesota/northern Iowa/southern Wisconsin
vicinity. Given a continuation of PWATs near 2" and
northwesterly steering flow to encourage training, a threat for
flash flooding may materialize. However, depending upon how
this evenings storms evolve, the higher threat area for flash
flooding could remain displaced to our northwest.
Tomorrow, the composite outflow is expected to temporarily
displace the most unstable airmass southwest of our area.
Onshore flow should provide relief to hot conditions with highs
expected to top off in the upper 70s lakeside to upper 80s well
inland. Heat indices may approach 100 southwest of a line from
Mendota to Paxton, in closer proximity to the residual front. A
few storms may develop by mid-afternoon in pulse-like fashion
along the front as well, warranting 20% PoPs mainly across
central IL.
KJB/Borchardt
Sunday Night through Saturday:
Forecast thinking during the long term period has not changed.
Please reference the previous discussion below for more info.
The story for the coming week will be continued heat and
humidity, especially on Monday, followed by a cooldown starting
Wednesday and likely persisting into the weekend.
Regarding the heat, Monday looks worse than Tuesday, with the
southwest portion of our forecast area perhaps again approaching
heat advisory levels for a brief period during the afternoon.
Temperatures Tuesday will still be quite summer-like, but low
level flow will be more westerly than southwesterly and
thunderstorm chances appear to be more widespread as a surface
low moving through the Great Lakes drags a trailing cold front
toward the area. Both days actually look to be supportive of
thunderstorms as the ridge aloft pushes more to our south
relative to its position on Sunday which should allow shortwaves
traversing the ridge axis to more directly influence the area.
For Monday this activity presently appears to be more of a
glancing blow favoring especially northern portions of the area
where lapse rates will also be most pronounced.
After the cold front passes through during the day on Tuesday,
the trailing surface high settles over the western Great Lakes
for the remainder of the week. By next weekend, models have this
feature slowly sliding east and allowing warmer and more humid
air to start working back into the area around its western
periphery. Wednesday and Thursday thus appear to be the coolest
days during the coming week, with highs topping out in the mid
70s in our north and near the lake, to mid 80s south. Aside from
the possibility of lingering activity early Wednesday, shower
and thunderstorm changes should also be most limited from
midweek onward, at least until the ridge moves east.
Lenning
&&
.AVIATION /18Z TAFS THROUGH 00Z MONDAY/...
Issued at 121 PM CDT Sat Aug 16 2025
Key messages:
- Strong gusty thunderstorms moving into the terminals 19Z to
22Z this afternoon. Gusts in excess of 40 possible with
northerly outflow.
- Scattered heavy rain producing storms may persist/redevelop
across parts of the area this evening. Confidence on the
coverage of these remains low at this time.
- Potential for a period of low MVFR to IFR CIGs early Sunday
morning.
A cluster of thunderstorms continues to drop southward with an
outflow boundary across southern WI. This outflow boundary is
expected to move into RFD, DPA and ORD around 1930Z (after 20z
at MDW and GYY), with a gusty northerly wind shift up to 40 kt.
Recent trends with the convection indicate that the outflow
boundary is running out well ahead of the areas of storms,
likely a result of weaker deep layer wind shear with southward
extent into northern IL. For this reason, the outflow may begin
to slow and potentially result in a later timing at the
terminals. Either way, the threat for thunderstorms will
increase across the area after 20Z this afternoon.
Thunderstorms may persist and our redevelop across parts of
northern IL this evening. The exact placement of this
redevelopment remains of low confidence, and will ultimately be
dependent upon the overall evolution of the ongoing activity
move towards the area this afternoon. For this reason, I have
continued to hold on to the PROB30 group for TS this evening.
Later tonight, winds will turn north-northeasterly off the lake.
While this should push the primary focus for thunderstorms south
of the terminals overnight, we will have to monitor the threat
for some low MVFR to IFR stratus for a couple hours Sunday
morning.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...Heat Advisory until 8 PM CDT this evening for ILZ010-ILZ019-
ILZ020-ILZ021-ILZ023-ILZ032-ILZ033-ILZ039-ILZ106-ILZ107-
ILZ108.
IN...None.
LM...None.
&&
Visit us at weather.gov/chicagoHazardous Weather Outlook
National Weather Service Chicago/Romeoville IL
400 AM CDT Sat Aug 16 2025...CORRECTED
ILZ003>006-008-010>013-019>021-023-032-033-039-103>108-INZ001-002-
010-011-019-170900-
Winnebago-Boone-McHenry-Lake IL-Ogle-Lee-De Kalb-Kane-DuPage-
La Salle-Kendall-Grundy-Kankakee-Livingston-Iroquois-Ford-
Northern Cook-Central Cook-Southern Cook-Northern Will-
Southern Will-Eastern Will-Lake IN-Porter-Newton-Jasper-Benton-
400 AM CDT Sat Aug 16 2025 /500 AM EDT Sat Aug 16 2025/
This Hazardous Weather Outlook is for portions of north central
Illinois...northeast Illinois and northwest Indiana.
.DAY ONE...Today and Tonight.
Weather hazards expected...
Elevated Excessive Heat Risk especially south of Interstate 80.
Elevated Thunderstorm Risk...with an associated:
Level 1 of 5 Damaging Wind Risk...up to 70 mph.
Level 1 of 5 Large Hail Risk...up to 1 inch in diameter.
Elevated Flooding Risk.
DISCUSSION...
A complex of thunderstorms is expected to move across the area
from north to south this afternoon and evening. Damaging winds are
the primary threat, which may locally exceed 70 mph. Additional
thunderstorms may develop overnight with a threat for flash
flooding.
.DAYS TWO THROUGH SEVEN...Sunday through Friday.
Sunday...
Limited Thunderstorm Risk.
Monday...
Elevated Excessive Heat Risk.
Limited Thunderstorm Risk...with an associated:
Level 1 of 5 Severe Thunderstorm Risk.
Limited Flooding Risk.
Tuesday...
Limited Thunderstorm Risk.
.SPOTTER INFORMATION STATEMENT...
Spotters may be needed this afternoon and evening.
GENERAL STORM MOTION OF THE DAY:
Moving toward the south at 35 to 40 mph.
LMZ740>745-170900-
Winthrop Harbor to Wilmette Harbor IL-
Wilmette Harbor to Northerly Island IL-
Northerly Island to Calumet Harbor IL-
Calumet Harbor IL to Gary IN-Gary to Burns Harbor IN-
Burns Harbor to Michigan City IN-
400 AM CDT Sat Aug 16 2025
This Hazardous Weather Outlook is for portions of the Illinois
nearshore waters of Lake Michigan and the Indiana nearshore
waters of Lake Michigan.
.DAY ONE...Today and Tonight.
Weather hazards expected...
Limited Thunderstorm Risk...with an associated:
Level 1 of 5 Thunderstorm Wind Gust Risk...up to 60 knots.
.DAYS TWO THROUGH SEVEN...Sunday through Friday.
Monday...
Limited Thunderstorm Risk...with an associated:
Level 1 of 5 Severe Thunderstorm Risk.
Tuesday...
Limited Thunderstorm Risk.
Borchardt
Visit us at www.weather.gov/chicagoThe Milwaukee radar (KMKX), 72 km away, was scanning. The volume nearest the first event began at 20:29 UTC.
70 thunderstorm wind, 13 hail, 1 lightning, 1 funnel cloud. Local standard time, as filed.
Woodstock PD reported multiple power lines downed around Woodstock.
Trees 3 to 4 feet in diameter were snapped along N Appleton Rd between Douglas and Maryland courts in Belvidere.
Seven trees were downed on the corner of 2nd St and Whitney Blvd, the largest being about 4 feet in diameter. Power lines were also reported down.
A tree had fallen onto a house along Clay St in Woodstock.
Boone County EM reported numerous trees down on the southeast side of Belvidere.
Numerous trees were reported down southeast of Crystal Lake, some onto cars and power lines.
Two trees two feet in diameter were downed and branches 6 to 12 inches in diameter were broken near Gardner and Jackson streets in Belvidere.
A tree was down onto 3 cars along Webster St in Algonquin.
Large branches were broken from the tops of trees near Main St and Cary Rd in Algonquin.
A tree was down along Woodcrest Ln in Algonquin.
Numerous trees and tree branches were down in Fox River Grove from Lions Park through the Foxmoor subdivision.
Numerous photos were shared of large branches and at least one uprooted tree in and around Cary.
Two large trees were down onto County Line Rd along the Cook-Kane county line.
The Village of Barrington reported multiple tree branches broken in the area.
A tree fell over a resident's fence at Coombs Rd and Highland Woods Blvd in Elgin.
A tree had fallen and was balancing on power lines along Castlewood Dr in Carpentersville.
A tree fell onto power lines and tore the lines away from a house along N East St in Lake Barrington.
A large tree fell and knocked down power lines along Old Hart Rd in Barrington.
A tree was down and blocking the road near Sleepy Hollow Road and Boncosky Rd in Sleepy Hollow.
Downed trees, tree branches, and power lines were reported in Barrington. Hail of unknown size was also reported.
A large tree branch was down and blocking Oak Knoll Rd west of Barrington.
A tree was down and blocking Lenz Rd near Muirhead Rd south of Plato Center.
A one foot diameter tree was snapped along Spaulding Rd in Bartlett.
Several tree limbs 8 to 12 inches in diameter were blown down near Mundhank Rd and S Freeman Rd in Hoffman Estates.
Numerous tree branches, most multiple inches in diameter, were broken southeast of Palatine. Additionally, at least one tree was split at its trunk and another was uprooted.
A softwood tree was uprooted and an 8 to 12 inch diameter limb was snapped in the vicinity of Greenbrier Rd in DeKalb.
Tree branches a few inches in diameter were downed in Schaumburg. A rotted tree was also uprooted nearby.
Numerous tree branches were downed on Cardinal Dr in Rolling Meadows.
A tree had fallen onto power lines along Knollwood Ct in Palatine.
Power poles were downed along Briarwood Ln in Palatine.
A tree was down and leaning on multiple houses near Heather Ct and Green Meadow Ct in Rolling Meadows.
A tree fell onto power lines along Old Wilke Rd in Rolling Meadows.
A tree fell onto power lines along Old Plum Grove Rd in Rolling Meadows.
Many large trees were uprooted, large branches were broken, and corn fields were flattened near Oaklawn Farm in Wayne.
A portion of a roof was removed from an apartment building near Huntington Commons Rd and Linneman Rd in Mount Prospect. Debris from the roof damaged nearby cars.
A tree fell onto power lines along Linneman Rd in Mount Prospect.
A tree fell onto power lines along S Vail Ave in Arlington Heights.
A tree fell onto power lines along Lancaster Ave in Mount Prospect.
A tree fell onto power lines along Owl Dr in Rolling Meadows. Caller reported seeing fire and smoke.
A power pole was snapped near Harter Rd and County Line Rd south of Maple Park.
A tree fell onto power lines near IL-47 and IL-64 in Maple Park cutting power to at least one house.
Trees were downed and numerous tents were blown around and destroyed during Niles Founders Day in Golf Mill Park.
Power lines were blown down and sparking at IL-31 and Silver Glen Rd in St. Charles.
A tree was blown down at IL-47 and Beith Rd north of Elburn.
Corn was flattened near Main St just west of Bunker Rd southeast of Elburn.
Trees were downed onto wires and vehicles on Main St in Elburn.
Power poles were snapped in half at Harter Rd and County Line Rd south of Maple Park.
Trees and power lines were reported down along IL-47 between US-88 and Main St.
A 50-foot tree was uprooted in the vicinity of Green and Bunker roads west of Batavia. Damage to a corn field was also noted in the area.
Multiple little trees roughly 5 inches in diameter were snapped in half at the Spring Bluff nursery in Sugar Grove.
Based on information provided by Aurora emergency management, extensive storm damage was reported across Aurora with the Aurora Police and Streets Departments having collectively received well over 100 reports for tree and power line damage. The highest concentration of reports came out of the west side of town, particularly in the area bound by Prairie St and Indian Trail Rd to the south and north and Edgelawn Dr and Highland Ave to the west and east, respectively.
Multiple trees were down along Bliss Rd northeast of Sugar Grove.
Trees were down on houses and blocking roads near Tanner Rd and Terrace Dr near North Aurora.
A tree was down and blocking Winthrop New Rd in Prestbury.
Power lines were downed along Norris Rd in Sugar Grove.
Multiple trees were down along and blocking Seavey Rd in western Kane County.
A tree was down and blocking the road at Hankes Rd and Densmore Rd in western Aurora.
A tree was down and blocking Exposition Ave in North Aurora.
A tree and power lines were blown down on Rockwell Rd in Aurora.
A 12 inch diameter tree was snapped at its base and several 3 to 6 inch diameter tree limbs were down in the vicinity of IL-53 and Short St in Lisle.
Trees were downed onto power lines and vehicles near Prairie St and Edgelawn Dr in Aurora.
A tree roughly 12 to 14 feet tall and 2 to 3 feet thick fell onto a wire along Stephen Dr in Montgomery.
A healthy tree had split and was blocking a residential road in Aurora.
Lightning struck a home along Hemingway Ct in Plainfield knocking out multiple electrical systems. Time was estimated based on radar data.
Roofing material was pulled off of a strip mall near IL-53 and Romeo Rd in Romeoville. A gas station canopy was also damaged and tilting nearby. Tree damage in the area extended from Romeoville High School north to Normantown Rd.
Multiple reports were received on social media for a funnel cloud in southern Will County. The most likely location based on the various reports appears to be over the Midewin Tallgrass Prairie in Wilmington.
Several large branches were broken in Lockport. The large trunk of a rotted tree also fell onto a house.
Whole trees were snapped in the vicinity of the Lockport High School baseball fields.
A tree was down in the road and power lines were down near the intersection of CRs 1300E and 2450N near Piper City.
Local broadcast media relayed photos of storm damage from CR 1200E west of Woodworth. Corrugated metal roofing was removed from a cattle shed and a portion of one of the walls collapsed. Wooden building material was found protruding from the ground. Damage to corn was also noted on the property.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Illinois in 2025Every state in 2025This day in weather historyWarnings in Illinois, August 2025
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: 1284185, 1284181, 1284182, 1284183, 1284184, 1284188, 1284186, 1284187, 1284189, 1284190, 1284191, 1284192, 1284198, 1284201, 1284202, 1284204, 1284210, 1285142, 1285143, 1285177, 1285178, 1284205, 1284206, 1284207, 1284208, 1284211, 1284212, 1284213, 1284561, 1284563, 1284564, 1284565, 1284216, 1284567, 1284568, 1284597, 1284598, 1284599, 1285167, 1285172, and more.