On the morning of July 11th, a derecho swept across northern Illinois leaving a wide swath of damage from severe winds. Comed, a utility company providing service to much of northern and northeast Illinois, deployed more resources after this storm than at any time in its history.
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.
On the morning of July 11th, a derecho swept across northern Illinois leaving a wide swath of damage from severe winds. Comed, a utility company providing service to much of northern and northeast Illinois, deployed more resources after this storm than at any time in its history. Over 1,100 crews from 14 states repaired or replaced 77.8 miles of wire, 600 poles and 1,000 transformers.
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 Jul 11, 4:11 AM CST, 1 hour 31 minutes earlier.
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
511 AM CDT MON JUL 11 2011
.DISCUSSION...
400 AM CDT
SEVERAL CONCERNS THIS FORECAST PERIOD RANGING FROM CHANCES FOR
CONVECTION IN THE NEAR TERM AS WELL AS ONCE AGAIN LATER
TODAY...AND HIGH TEMPERATURES/INDICES POSSIBLE TODAY.
LATEST RADAR IMAGERY THIS MORNING SHOWING CLUSTER OF THUNDERSTORMS
TO THE NORTH/NORTHWEST MOVING EAST THROUGH PORTIONS OF
MINNESOTA/IOWA AND WISCONSIN. MAIN QUESTION IN THE NEAR TERM IS IF
THIS SYSTEM WILL HOLD ITSELF TOGETHER AS IT MOVES TO THE
EAST/SOUTHEAST. LATEST RUC ANALYSIS IS SHOWING A STRONGLY UNSTABLE
ATMOSPHERE IN PLACE WITH MAIN INSTABILITY AXIS EXTENDING FROM IOWA
SOUTHEAST INTO ILLINOIS. DESPITE MODEST BULK SHEAR VALUES IN PLACE
FROM THIS SYSTEM SOUTHEAST INTO NORTHERN ILLINOIS...CURRENT
THINKING IS THAT THIS SYSTEM WILL NOT MAKE IT QUITE THIS FAR SOUTH
INTO THE CWA THIS MORNING...OR AT LEAST WITH A SEVERE PUNCH.
LATEST WIND PROFILER DATA IS ALREADY SHOWING THE 850MB WINDS/LLJ
VEERING OUT AHEAD OF THIS SYSTEM. LATEST SHORT TERM GUIDANCE IS
INDICATING THAT THIS VEERING WILL CONTINUE OUT AHEAD OF THIS
SYSTEM THROUGH THIS MORNING. AS THIS OCCURS...THIS UPSTREAM SYSTEM
WILL LOSE THIS LLJ AXIS BUT CONTINUE TO THE EAST RIDING ALONG
WITH ITS FORCING/MID LEVEL WAVE. DO THINK THERE MAY BE SOME
REMNANT SHOWERS/ISOLATED THUNDER ON THE SOUTHERN FRINGE OF THIS
SYSTEM MAINLY AFFECTING THE FAR NORTHERN COUNTIES IN THE CWA.
ALTHOUGH THIS WILL LIKE BE DUE TO STRONG SOUTHERLY FLOW RIDING
OVERHEAD OF SURFACE WARM FRONT LIFTING TO THE NORTH. WITH ONCE
AGAIN NO SEVERE WEATHER ANTICIPATED IN THE IMMEDIATE NEAR TERM.
ACTUALLY OF MORE CONCERN RIGHT NOW IS ANOTHER CLUSTER OF
THUNDERSTORMS WHICH IS PROPAGATING ACROSS IOWA THIS MORNING. THIS
IS RIDING ALONG AN UPSTREAM STRONG MID LEVEL WAVE EJECTING OUT
ACROSS THE PLAINS AND BEING FEED BY STRONGER AND MORE DEFINED
850MB WINDS. AS THIS WAVE CONTINUES TO SHIFT TO THE EAST ACROSS
THE CENTRAL PLAINS THIS MORNING...ASSOCIATED CONVECTION WILL ALSO
MOVE ALONG WITH IT. HOW STRONG THIS SYSTEM WILL BE BY THE TIME IT
ARRIVES IS STILL IN QUESTION...WHICH WOULD BE SOMETIME AROUND
12Z. BUT I THINK AS THIS WAVE ENCOUNTERS POSSIBLE LINGERING
OUTFLOW BOUNDARIES AND AN APPROACHING COLD FRONT TO THE
NORTHWEST...AS WELL AS SREF/NAM/GFS ALL INDICATING A CONTINUED
INCREASE IN INSTABILITY WITH A STRONGLY UNSTABLE ATMOSPHERE TO BE
CENTERED OVERHEAD THROUGH MID DAY...WITH ANY CAP ALSO WEAKENING
THROUGH 18Z...CONVECTION WILL REDEVELOP/STRENGTHEN ONCE AGAIN OVER
THE AREA AND MOVE SOUTHEAST AFFECTING MUCH THE CWA...AS IT RIDES
ALONG THE UPPER LEVEL RIDGE WITH STRONG DAMAGING WINDS THE MAIN
THREAT.
HEAT TODAY ALSO REMAINS SOMEWHAT IN QUESTION. THE QUESTION WILL
NOT BE HOW WARM OF AN ENVIRONMENT WILL BE IN PLACE...BUT RATHER
THE PREVIOUSLY MENTIONED FACTORS WHICH COULD COME INTO PLAY AND
LIMIT STRONG WARMING. THIS PRECIP/CLOUD COVER COULD PLAY A PART
WITH THIS WARMING BUT WITH 850 TEMPS DEFINITELY UP THERE AS MAIN
THERMAL AXIS SHIFTS OVER THE CWA AND DEWPOINTS ALSO UP THERE WITH
GOOD MOISTURE POOLING OUT AHEAD OF APPROACHING COLD FRONT...WITH
DEWPOINTS IN THE MID AND UPPER 70S IN PLACE...DONT THINK IT WILL
TAKE MUCH FOR ADVISORY CRITERIA TO BE MET IN THE SOUTHERN MOST
TIER OF COUNTIES. CURRENT THINKING IS THAT THIS PRECIP/CLOUD COVER
SHOULD ONLY AFFECT THIS AREA FOR A PART OF THIS MORNING...AND WITH
GOOD WARMING STILL A DEFINITE POSSIBILITY FOR THE REMAINDER OF THE
DAY. SO HAVE DECIDED TO INCLUDE THIS SOUTHERN TIER OF COUNTIES IN
A HEAT ADVISORY FROM 17Z TODAY THROUGH 00Z TONIGHT AS HEAT INDICES
WILL RANGE FROM 105-110.
RODRIGUEZ
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 10Z...
* THUNDERSTORM POTENTIAL THIS MORNING AND TRENDS LATER TODAY.
* WIND DIRECTION IN RESPONSE TO CONVECTIVE COLD POOL/HIGH PRESSURE
BUBBLE ACROSS IOWA.
RATZER
//DISCUSSION...UPDATED 10Z...
AREA OF SEVERE THUNDERSTORMS OVER IOWA IS EXPECTED TO CONTINUE TO
PROPAGATE EASTWARD REACHING KRFD AROUND 12Z...AND CHICAGO
TERMINALS AROUND 13Z THIS MORNING. STRONGEST PORTION OF THIS LINE
OF STORMS MAY AFFECT MAINLY FAR NORTHERN IL AND THE IL/WI BORDER
REGION...WHILE CONVECTION FARTHER SOUTH INTO IL MAY BECOME A
LITTLE MORE SCATTERED DUE TO STRONGER CAPPING INVERSION AND LESS
DEEP SHEAR DOWNSTATE. WOULD EXPECT MAIN THUNDER THREAT TO LAST A
COUPLE OF HOURS...FOLLOWED BY SHOWERS TRAILING THE MAIN LINE. MUCH
UNCERTAINTY THEN EXISTS FROM LATE MORNING INTO THE AFTERNOON HOURS
AS TO REDEVELOPMENT. WOULD SUSPECT GREATER CHANCES FOR MORE
ORGANIZED CONVECTION WOULD BE SOUTH/EAST OF THE TERMINALS AS
OUTFLOW FROM MORNING ACTIVITY WILL LIKELY BECOME FOCUS FOR
RENEWED STRONG STORMS.
WINDS WILL INITIALLY TURN MORE WESTERLY THIS MORNING...THOUGH
CONVECTION AND HIGH PRESSURE BUBBLE BEHIND IT MAY PRODUCE PERIOD
OF VARIABLE DIRECTION FOR A TIME LATER THIS MORNING.
RATZER
PREVIOUS DISCUSSION FROM 06Z...
ISOLATED SHOWERS AND THUNDERSTORMS FROM EARLIER THIS EVENING HAVE
ENDED FOR NORTHERN IL...AND THE FOCUS TURNS TOWARDS THE COMPLEX OF
THUNDERSTORMS OVER MINNESOTA AND NEBRASKA. GUIDANCE CONTINUES TO
SUGGEST THAT REMNANTS OF THE NORTHERN COMPLEX WILL FLOAT OVERHEAD
AROUND DAYBREAK...WITH A RESURGENCE OF CONVECTION MIDDAY THROUGH
THE AFTERNOON HOURS. TIMING OF THE SECOND CONVECTIVE EPISODE IS
QUESTIONABLE WITH DEBRIS CLOUDS FROM THE OVERNIGHT COMPLEX PUSHING
OVER NORTHERN IL/NORTHWEST IN. WILL UTILIZE A PROB30 GROUP TO
HANDLE THE MIDDAY CONVECTION AT THIS TIME.
WINDS WILL CONTINUE TO BE SOUTHERLY THROUGH THE OVERNIGHT
PERIOD...HOWEVER SPEED SHOULD HOVER AROUND 4 TO 6 KT. WITH
ABUNDANT LLVL MOISTURE STREAMING NORTH...EXPECT SOME HZ SKIES TO
OCCUR. NOT EXPECTING MUCH OF AN IMPACT TO THE VSBYS...HOWEVER A
BRIEF DIP TO AROUND 3 TO 5 SM IS POSSIBLE.
FRONTAL BOUNDARY WILL STEADILY SAG SOUTH ACROSS NORTHERN
IL/NORTHWEST IN...WITH A CONTINUED CHANCE FOR AFTN SHRA/TSRA AFT
16Z THRU 00Z. GUIDANCE IS A LITTLE QUICKER WITH PUSHING THE FRONT
THROUGH...HOWEVER FEEL A SLOW DOWN TO THE BOUNDARY IS IN ORDER DUE
TO THE LACK OF FORCING.
BEACHLER
//ORD AND MDW CONFIDENCE...UPDATED 10...
* MEDIUM-HIGH CONFIDENCE IN CONVECTION TRENDS THIS AM.
* MEDIUM CONFIDENCE IN WIND FORECAST.
* LOW CONFIDENCE IN CONVECTIVE TRENDS BEYOND MID MORNING.
RATZER
//OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z...
TUESDAY...VFR. CHC TSRA IN THE EVENING HOURS.
WEDNESDAY...VFR.
THURSDAY...VFR. SLIGHT CHC TSRA IN THE EVENING.
FRIDAY...VFR. SLIGHT CHC TSRA.
SATURDAY...VFR. SLIGHT CHC TSRA.
BEACHLER
&&
.MARINE...
255 AM CDT
LOW PRESSURE CONTINUES TO SKIRT ACROSS ONTARIO THIS MORNING...WITH
A COLD FRONT THAT IS DRAPED TO THE SOUTHWEST...AND ALSO WITH SHOWERS
AND THUNDERSTORMS ALONG IT. THOSE SHOWERS AND THUNDERSTORMS WILL
CONTINUE THIS MORNING...MOVING TO THE EAST AND SOUTHEAST...AND
POTENTIALLY EXIST ACROSS THE SOUTHERN HALF THIS AFTERNOON AND
EVENING. AS THE FRONT MOVES THROUGH...WINDS WILL TURN TO THE WEST
AND THEN TO THE NORTH...BUT WILL NOT LIKELY GUST HIGHER THAN FORCE
TWO TO THREE THROUGH TOMORROW EVENING AS COOLER AIR WORKS SOUTH
FROM CANADA. WITH THE LONG FETCH...THERE WILL BE THE POTENTIAL FOR
A SMALL CRAFT ADVISORY ON WEDNESDAY...PRIMARILY DUE TO
WAVES...BUT CANNOT RULE OUT A FEW GUSTS AOA CRITERIA. HIGH
PRESSURE WILL THEN BUILD IN FROM THE DAKOTAS...SETTLE OVER THE
GREAT LAKES BY MIDWEEK...AND ABATE ANY STRONGER WINDS OR HIGHER
WAVES THROUGH THE END OF THE WEEK.
SHEA
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...HEAT ADVISORY...ILZ023-ILZ032-ILZ033-ILZ039...NOON MONDAY TO 7
PM MONDAY.
IN...HEAT ADVISORY...INZ010-INZ011-INZ019...NOON MONDAY TO 7 PM
MONDAY.
LM...NONE.
&&HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL 453 AM CDT MON JUL 11 2011 ILZ003>006-008-010>014-019>023-032-033-039-INZ001-002-010-011-019- 121000- WINNEBAGO-BOONE-MCHENRY-LAKE ILLINOIS-OGLE-LEE-DE KALB-KANE- DUPAGE-COOK-LA SALLE-KENDALL-GRUNDY-WILL-KANKAKEE-LIVINGSTON- IROQUOIS-FORD-LAKE INDIANA-PORTER-NEWTON-JASPER-BENTON- 453 AM CDT MON JUL 11 2011 /553 AM EDT MON JUL 11 2011/ THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH CENTRAL ILLINOIS... NORTHEAST ILLINOIS AND NORTHWEST INDIANA. .DAY ONE...TODAY AND TONIGHT. WEATHER HAZARDS EXPECTED: THUNDERSTORMS...SOME OF WHICH COULD PRODUCE: HAIL TO ONE INCH. STRONG DAMAGING WIND GUSTS IN EXCESS OF 60 MPH. LOCALLY HEAVY RAINFALL. AREAS AFFECTED AND TIMING: ALL OF NORTHERN ILLINOIS AND NORTHWEST INDIANA EARLY THIS MORNING THROUGH THIS AFTERNOON. DISCUSSION: A CLUSTER OF THUNDERSTORMS WILL CONTINUE TO SHIFT EAST INTO NORTHERN ILLINOIS AND NORTHWEST INDIANA EARLY THIS MORNING AS A MID LEVEL DISTURBANCE TRACKS EAST ACROSS THE REGION. AS THESE THUNDERSTORMS MOVE EAST...THEY WILL ENCOUNTER A STRONGLY UNSTABLE AND MOISTURE RICH ATMOSPHERE WHICH WILL ENABLE THESE STORMS TO MAKE A STRONG PUSH EAST THIS MORNING. ALTHOUGH LARGE HAIL WILL BE POSSIBLE...THE MAIN THREAT WITH THESE STORMS WILL BE STRONG DAMAGING WIND GUSTS AS WELL AS LOCALLY HEAVY RAINFALL. TEMPERATURES ARE FORECAST TO REACH THE LOWER 90S WITH HIGH HUMIDITY CONTRIBUTING TO HEAT INDEX VALUES OF 105 TO 110 DEGREES SOUTH OF A LINE FROM LIVINGSTON COUNTY IN ILLINOIS EAST TO JASPER COUNTY IN INDIANA...WITH ALL OTHER AREAS IN NORTHERN ILLINOIS AND NORTHWEST INDIANA FORECAST TO OBSERVE HEAT INDEX VALUES OF AROUND 100 DEGREES. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY. THERE WILL BE PERIODIC CHANCES FOR THUNDERSTORMS TUESDAY THROUGH SATURDAY. .SPOTTER INFORMATION STATEMENT... SPOTTERS WILL LIKELY BE NEEDED EARLY THIS MORNING THROUGH THIS AFTERNOON. && COMPLETE FORECAST INFORMATION IS AVAILABLE ON THE NWS CHICAGO WEBPAGE: WEATHER.GOV/CHICAGO LMZ740>745-121000- WINTHROP HARBOR TO WILMETTE HARBOR- WILMETTE HARBOR TO NORTHERLY ISLAND- NORTHERLY ISLAND TO CALUMET HARBOR-CALUMET HARBOR TO GARY- GARY TO BURNS HARBOR-BURNS HARBOR TO MICHIGAN CITY- 453 AM CDT MON JUL 11 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE ILLINOIS NEARSHORE WATERS OF LAKE MICHIGAN AND THE INDIANA NEARSHORE WATERS OF LAKE MICHIGAN. .DAY ONE...TODAY AND TONIGHT. THERE IS A CHANCE OF THUNDERSTORMS EARLY THIS MORNING THROUGH THIS AFTERNOON WITH WINDS OF 34 KNOTS OR GREATER POSSIBLE WITH THE STRONGEST THUNDERSTORMS. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY. THERE IS A CHANCE OF THUNDERSTORMS TUESDAY THROUGH TUESDAY NIGHT AND ONCE AGAIN ON FRIDAY THROUGH FRIDAY NIGHT. && COMPLETE FORECAST INFORMATION IS AVAILABLE ON THE NWS CHICAGO WEBPAGE: WEATHER.GOV/CHICAGO LMZ080-261-362-364-366-563-565-567-669-671-673-675-777-779-868- 870-872-874-876-878-121000- LAKE MICHIGAN FROM MICHIGAN CITY IN TO ST. JOSEPH MI 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM SEUL CHOIX POINT TO ROCK ISLAND PASSAGE 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN SOUTH OF A LINE FROM SEUL CHOIX POINT TO THE MACKINAC BRIDGE AND NORTH OF A LINE FROM CHARLEVOIX MI TO SOUTH FOX ISLAND 5 NM OFFSHORE- LAKE MICHIGAN FROM CHARLEVOIX TO POINT BETSIE MI 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM POINT BETSIE TO MANISTEE MI 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM ROCK ISLAND PASSAGE TO STURGEON BAY WI- LAKE MICHIGAN FROM STURGEON BAY TO TWO RIVERS WI 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM TWO RIVERS TO SHEBOYGAN WI 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM SHEBOYGAN TO PORT WASHINGTON WI 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM PORT WASHINGTON TO NORTH POINT LIGHT WI 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM NORTH POINT LIGHT TO WIND POINT WI 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM WIND POINT WI TO WINTHROP HARBOR IL 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM WINTHROP HARBOR TO WILMETTE HARBOR IL 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM WILMETTE HARBOR IL TO MICHIGAN CITY IN 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM PENTWATER TO MANISTEE MI 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM WHITEHALL TO PENTWATER MI 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM GRAND HAVEN TO WHITEHALL MI 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM HOLLAND TO GRAND HAVEN MI 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM SOUTH HAVEN TO HOLLAND MI 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM ST. JOSEPH TO SOUTH HAVEN MI 5 NM OFFSHORE TO MID LAKE- 453 AM CDT MON JUL 11 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE OPEN WATERS OF LAKE MICHIGAN. .DAY ONE...TODAY AND TONIGHT. THERE IS A CHANCE OF THUNDERSTORMS EARLY THIS MORNING THROUGH THIS AFTERNOON WITH WINDS OF 34 KNOTS OR GREATER POSSIBLE WITH THE STRONGEST THUNDERSTORMS. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY. THERE IS A CHANCE OF THUNDERSTORMS TUESDAY THROUGH TUESDAY NIGHT MAINLY FOR THE SOUTHERN HALF OF LAKE MICHIGAN...AND ONCE AGAIN THURSDAY NIGHT THROUGH FRIDAY NIGHT FOR THE ENTIRE LAKE. && COMPLETE FORECAST INFORMATION IS AVAILABLE ON THE NWS CHICAGO WEBPAGE: WEATHER.GOV/CHICAGO RODRIGUEZ
The Quad Cities radar (KDVN), 85 km away, was scanning. The volume nearest the first event began at 11:40 UTC.
86 thunderstorm wind, 5 lightning. Local standard time, as filed.
Corn fields were flattened, and 6-inch diameter branches were blown down along with power lines.
Portions of a corn field were flattened near Harmon Road and Rock Island Road.
Corn fields were flattened near the intersection of Route 20 and Conger Road.
Winds were estimated to 60 mph outside of WREX television studio.
A semi-truck was overturned in Loves Park on Perryville Road between Harlem Road and Mulford Road. State Street was closed from 9th Street to Division after a large tree was blown down taking down power lines. Rockford Park District reported that 25 parks and facilities sustained some type of storm damage, mostly from fallen trees.
High winds blew down several power lines along Alpine Road just north of East Riverside Boulevard.
Winds estimated to 70 mph blew down 12-inch diameter trees, including one that fell onto the roadway blocking Spring Street.
Portions of a corn field were flattened near Amboy.
In the town of Creston, two large trees were blown down and three telephone poles were leaning. Corn in the area was flattened. A metal barn was blown over halfway between Malta and Creston on the north side of Route 38.
Power lines were blown down and were blocking eastbound lanes of Interstate 90 near Boone McHenry County Line Road.
Route 251 was blocked by downed power lines near Spur Road.
Winds gusting 70 to 80 mph damaged power transformers and blew over a semi-truck.
Numerous trees fell across Belvidere causing damage to powerlines and roofs. One tree fell against a house on Garden Drive while another fell onto a roof on East Lincoln Avenue.
Over 30 large trees were reported down in the Poplar Grove and Candlewick Lake area, including one tree that fell onto a house on Bounty Drive in Candlewick Lake and a tree that fell onto a car in Poplar Grove. Also in Poplar Grove, a roof was blown off of a house and a garage was destroyed.
Trees were snapped at the base just south of Route 38 on Annie Glidden Road. Corn was flattened in areas surrounding De Kalb.
Winds estimated to 70 mph caused several trees to snap. One large oak tree fell onto a house and car, but damage to property was minimal. The press box at DeKalb High School was blown over. The building was secured by pilings set in concrete, which were pulled out of the ground. Power lines were downed near Normal Road and 10th Street. A tree limb fell onto a home and damaged the gas meter. Portions of a corn field were flattened in Waterman.
Numerous 12-inch diameter trees and power lines were blown down. Some trees were snapped. One tree fall onto a house.
A roof was blown off of a house and a garage was destroyed.
Winds were estimated to 60 mph.
Patches of a corn field were flattened on the intersection of Keslinger Road and Dauberman Road.
In the Meadowbrook neighborhood, there were numerous houses with the siding ripped off. Multiple trees were uprooted or snapped at the base. One house on Waterford Lake had the chimney blown off.
Winds to 65 mph were measured with an anemometer. A tree was blown down on Beith Road.
A large limb was dislogded from a tree and broke through the siding of a house going into the master bedroom. No one was injured.
Winds estimated to more than 70 mph lasted for two to three minutes causing 1-foot diameter trees and large branches to blow over as well as power outages. Large limbs fell through the windshield of a car at an intersection on Dole Avenue.
Numerous tree limbs, some around 6 inches in diameter, were blown down causing damage to powerlines.
Lightning struck a 40-foot oak tree which then fell onto a car, blowing out the rear window and heavily damaging the trunk and vinyl roof of the convertible. The tree also caused some damage to the roof and gutter of a garage.
Downed trees caused damage to fences in some parts of McHenry. A Chevrolet Traverse had its windshield smashed.
Large tree limbs were blown down.
Deerpath Road just west of Batavia was closed due to several power poles hanging over roadways. An power pole on North Kirk Road was also leaning over the roadway.
Winds were estimated to 60 mph and caused damage to power transformers.
A 4 to 5 inch diameter tree was blown down as were several large limbs. A backyard wooden jungle gym was destroyed.
Fences were blown down and an 8-inch diameter tree was snapped near Hintz Road and Windsor Drive. At Arlington Park Race Track, 4 to 6 inch diameter branches were blown down. Numerous trees and power lines were also down across the area. There was a report of a window blown out of a house.
Numerous tree limbs of up to 8 inches in diameter were blown down.
Wind gusts were estimated between 60 and 70 mph.
Wind gusts were estimated to 60 mph causing intermittent power failures.
A portion of a roof was peeled off by strong winds on Church Street.
Tree limbs of up to 4 inches in diameter were blown down. Some large trees were snapped, blocking roads.
Numerous large trees and tree limbs were blown over. A traffic light on Naperville Road was blown down.
A large tree, greater than two feet in diameter, was uprooted and fell onto the roof of a house near the intersection of Gary's Drive and North Avenue.
A 12-inch tree fell on a house near the intersection of Windsory Drive and Palatine Road. An 18-inch tree was also uprooted nearby.
A lightning strike ignited a fire in the steeple of a former church on Hill Road. There was slight damage to the roof and some water damage.
A tree approximately two feet in diameter was snapped at the base and fell onto the roadway blocking traffic near the intersection of Princeton Avenue and Grove Street.
A few roofs were blown off of buildings in the Lincolnshire-Riverwoods district.
Winds were estimated to 60 mph.
Telephone lines were blown down along with large trees in Prairie View. A roof was blown off.
Large branches fell onto a parked car in northwest Prospect Heights causing moderate damage including a shattered back window.
Lightning struck a village pump house on Valley Drive melting wiring and destroying the water pump.
A 15-inch diameter tree was uprooted by winds estimated to 70 mph.
Numerous tree branches 18 to 24 inches in diameter were blown down. Power lines were blown down. The road was blocked on 63rd Street between Fairview Avenue and Belmont Road.
Large tree branches were blown down.
A semi-truck was blown over on Interstate 94 near Route 176.
A one-foot diameter branch was blown down with numerous smaller branches on Harvard Street between Clarence Avenue and East Avenue.
A lightning strike caused a fire on the 1100 block of Bards Avenue.
A large tree limb fell onto a roof on the 8600 block of Center Street damaging portions of the roof and awning.
Downed power lines sparked a fire that spread to four cars. Two of the cars were totaled, with the interiors completely burned.
A 24-inch diameter tree was blown down at the intersection of Oakton Street and Wesley Avenue. Other trees were blown down in the area.
Tree limbs 5 to 6 inches in diameter were blown down along 62nd Street. A 20-inch diameter tree was split vertically down the middle.
Trees two feet in diameter were snapped and utility poles were blown down near the intersection of Checker Road and Schaeffer Road.
Utility poles were snapped by strong winds.
Wind gusts estimated to 65 mph blew down at least six large trees in Loyola Park near the lakefront. Diameters were estimated between 18 and 24 inches.
The roofs of two buildings on the 9600 block of Lois Drive were ripped off by strong winds.
A 74-inch diameter tree known as the Bicentennial Ash was blown down in Gillson Park.
A tree approximately two feet in diameter fell onto a moving vehicle causing heavy damage to the car. The incident occurred near the 4900 block of North Austin Avenue. No injuries were reported.
Shed walls were blown in and several large branches were blown down.
Winds were estimated to 65 mph near the intersection of Route 59 and Caton Farm Road.
A large tree limb, estimated at more than a foot in diameter, fell onto a roof on the 8800 block of Burlington Avenue.
Tree branches 4 to 6 inches in diameter and 15 feet long were blown down near the intersection of Wadsworth Road and Delaney Road.
Wind gusts were estimated to 60 mph.
Numerous large tree limbs were blown down onto streets.
Strong winds ripped a couple roofs off of buildings in the industrial area of Bedford Park. A parapet wall on another building was heavily damaged with bricks falling onto the sidewalk below. Three cars were damaged by falling trees and limbs.
Tree branches 6 to 8 inches in diameter were blown down near the intersection of Miller Road and Route 12.
A large tree, approximately 18 inches in diameter, was blown down near the intersection of Goethe Street and LaSalle Street.
Winds were measured to 75 mph at Midway Airport as well as an observer approximately 3 miles southwest of Midway Airport. A semi was overturned near the intersection of 65th Street and Menard Avenue. Fences and 10-inch diameter branches were blown down. Large trees were reported down near Midway Airport. Sheet metal and shingles were torn off roofs. Power lines and poles were blown down, including one pole that fell onto a house in Burbank. Winds were estimated to 65 mph in Hometown.
A 12-inch diameter tree limb was blown down at the intersection of Dayton Street and Willow Street.
Large branches were blown off trees. Winds were estimated to 60 mph.
Trees eight inches in diameter were snapped near the intersection of Route 60 and Peterson Road.
Winds were estimated to 60 mph causing some tree damage.
A festival tent at 109th Street and 88th Avenue near Moraine Valley Community College was lifted and then dropped onto six workers causing minor injuries.
Tree branches up to 8 inches in diameter were blown down.
A 12-inch diameter tree was blown down. Winds were estimated to 60 mph.
A large tree limb smashed a car causing heavy damage to the rear of the car on the 3600 block of Rockwell Avenue.
Several 4-inch diameter trees were blown down.
A 12 to 15 inch diameter tree was blown down. The roof of a 32-unit apartment building was torn off.
Winds were measured to 72 mph in Evergreen Park. At the intersection of 88th Street and Utica Avenue, a 12-inch diameter tree was snapped at the base.
A 72 year old man was driving on the 3000 block of West Ogden Avenue when a tree limb fell through the sunroof of his car striking the man. The man died in the hospital during the afternoon of July 12th.
A mature tree was blown over, crushing the front end of a car on the 9900 block of South Bell Avenue. Another tree fell onto a roof of a home on the 10600 block of South Hoyne Avenue. This tree damaged the roof of the home, a fence, a porch railing, and a concrete slab.
Lightning struck a large tree which then fell onto a storage building, shifting the roof and making it unsafe to enter.
As the offices recorded each death: direct deaths were caused by the weather itself, indirect ones by something it set in motion.
| Event | Date | Age | Sex | Where | Kind |
|---|---|---|---|---|---|
| Thunderstorm Wind, Cook | 2011-07-11 | 72 | Male | Vehicle/Towed Trailer | Direct |
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Illinois in 2011Every state in 2011This day in weather historyWarnings in Illinois, July 2011
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: 333905, 331187, 338306, 331194, 331193, 338272, 331196, 338290, 331204, 333909, 333911, 333930, 338308, 333943, 333968, 336294, 336296, 336297, 336300, 338337, 336304, 336305, 336306, 340195, 336309, 338333, 340199, 340201, 336325, 338340, 336311, 338326, 336312, 336316, 336319, 336320, 336321, 336322, 336323, 336324, and more.