Strong thunderstorms moved across parts of northern Illinois during the early morning hours of June 15th. Behind this area of thunderstorms strong winds developed from a wake low, which produced damage in some areas.
Every event with a place to put it; 1 filed by county or forecast zone are drawn at its center, in a lighter ring. 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.
Strong thunderstorms moved across parts of northern Illinois during the early morning hours of June 15th. Behind this area of thunderstorms strong winds developed from a wake low, which produced damage in some areas.
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 Jun 15, 2:18 AM CST, 2 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL 318 AM CDT WED JUN 15 2011 .DISCUSSION... 130 PM CDT TONIGHT THROUGH WEDNESDAY... MAIN CONCERN FOR THE OVERNIGHT PERIOD THROUGH WEDNESDAY CONTINUES TO BE QPF TOTALS...AND TEMPERATURES AS UNCERTAINTY AMONGST SOLUTIONS CONTINUES. ANTI-CYCLONIC FLOW CENTERED OVER THE GREAT LAKES CONTINUES TO CONTROL THE WEATHER THIS AFTERNOON...HOWEVER BASED ON LATEST ANALYSIS AND HI-RES GUIDANCE THIS FEATURE WAS BEGINNING TO DRIFT NORTHEAST. DOWNSTREAM A SHORTWAVE CONTINUES TO HOLD OFF OF THE NEW ENGLAND COAST...WITH A HIGH LATITUDE BLOCK OVER GREENLAND. BOTH OF THESE FEATURES ARE ALSO BEGINNING TO WEAKEN EVER SO SLIGHTLY...WHICH SHOULD ALLOW THE ATMOSPHERE OVER THE CENTRAL PLAINS/GREAT LAKES TO BECOME MORE FLUID. ADDITIONALLY A 500MB VORT CONTINUES TO LIFT NORTHEAST FROM THE DAKOTAS INTO WESTERN ONTARIO WEDNESDAY. THIS WILL AID IN FURTHER EJECTING THE EAST COAST TROUGH. EXTENDING SOUTHEAST FROM THE NORTHERN PLAINS MID-LVL VORT WAS A WEAK TROUGH THAT HAS BEEN A FOCAL POINT FOR ABUNDANT MOISTURE. 850MB V-WIND OR MOISTURE TRANSPORT HAS CONTINUE TO BE FROM THE SOUTH...AND IS EXPECTED TO PERSIST...THUS ADDITIONAL MOISTURE IS EXPECTED TO ADVECT NORTH FROM THE GULF OF MEXICO INTO THIS BOUNDARY. LATE THIS AFTERNOON THE BEST FORCING FOR CONVECTION CONTINUES TO BE SOUTHERN MINNESOTA/IOWA STRETCHING SOUTHEAST THROUGH SOUTHWEST ILLINOIS AND EASTERN MISSOURI. STRONGER SHEAR AND LLVL INSTABILITY WAS POSITIONED OVER MISSOURI/SOUTHWEST ILLINOIS...WHERE THE BEST CHANCE FOR SEVERE WEATHER EXISTS TONIGHT. AS MID-LVL HEIGHTS OVERNIGHT RELAX...THE BAROCLINIC ZONE WILL STEADILY DRIFT NORTHEAST TOWARDS THE GREAT LAKES REGION. THIS WILL ALLOW THE ATMOSPHERIC RIVER THAT HAS PRODUCED ABUNDANT RAINFALL ACROSS IOWA/MISSOURI TO BECOME POSITIONED OVER WISCONSIN/ILLINOIS/INDIANA. THE CHALLENGE AS PREVIOUSLY MENTIONED IS HOW MUCH PRECIPITATION WILL FALL OVER THE CWFA. SREF PRECIP PLUMES CONTINUE TO DEMONSTRATE CONSIDERABLE SPREAD OR NOISE...WITH A RANGE BETWEEN 0.25 TO 3 INCHES. HAVE OPTED TO UTILIZE THE MEAN AMONGST THE SREF MEMBERS WITH THIS FORECAST PACKAGE AND A RANGE BETWEEN 0.5 AND 1 INCH...HOWEVER THE POTENTIAL EXISTS THAT PRECIP TOTALS COULD BE HIGHER...DEPENDING ON ANY TRAINING OF SHOWERS/THUNDERSTORMS THAT MAY OCCUR. 850MB V-WINDS REMAIN RATHER WEAK...WHICH COUPLED WITH THE HISTORY OF PRODUCING HEAVY RAIN FROM THIS BOUNDARY COULD BE ENOUGH TO SIDE MORE WITH A HIGHER QPF TOTAL. WITH CONSIDERABLE SOLAR SHIELDING ANTICIPATED OVER THE NEXT 24 HOURS...TEMPERATURES WILL STRUGGLE TO WARM SUBSTANTIALLY ACROSS THE CWFA. GUIDANCE MEMBERS HAVE CONTINUED TO SUGGEST TEMPERATURES WILL COOL INTO THE UPPER 50S/LOWER 60S OVERNIGHT...THEN ONLY WARM INTO THE LOW 70S WEDNESDAY. WEDNESDAY NIGHT THROUGH FRIDAY... SFC RIDGE THEN PUSHES EAST INTO THE MISSOURI VALLEY...WHICH SHOULD AID IN INCREASING THE FORWARD SPEED OF THE FRONTAL BOUNDARY LATE WEDNESDAY NIGHT. ACROSS NORTHERN IL/NORTHWEST IN ENOUGH DRY AIR COULD PUSH OVERHEAD TO PROVIDE A BRIEF PERIOD OF DRY WEATHER THUR/FRI...HOWEVER AS PREVIOUSLY NOTED ABOUT THE ATMOSPHERE BECOMING MORE FLUID SLIGHT CHANCE FOR SHOWERS/THUNDERSTORMS MAY NEED TO REMAIN FOR BOTH OF THESE PERIODS. SATURDAY THROUGH MONDAY... ENSEMBLES CONTINUE TO DEMONSTRATE MINIMAL SPREAD OR A HIGH CONFIDENCE IN A WARMING TREND FOR THE WEEKEND INTO EARLY NEXT WEEK. PAC-NW SYSTEM CONTINUES TO PUSH ONSHORE WHICH WILL AID IN FURTHER AMPLIFICATION OF THE DOWNSTREAM RIDGE ACROSS THE CENTRAL PLAINS. THIS SCENARIO SHOULD STRENGTHEN THE ANTICIPATED WARMING TREND FOR THE WEEKEND...WITH A POTENT 850MB THERMAL RIDGE OF 20 TO 22 DEG C ANTICIPATED SUN. THIS SHOULD PUSH SFC TEMPS INTO MID/UPR 80S AND POSSIBLY 90 DEG SUN/MON. RISING DEW POINTS OVER THE WEEKEND WILL ALSO INCREASE THE HUMIDITY...WHICH MAY CREATE HEAT INDEX VALUES IN THE MID/UPR 90S. PWAT VALUES WILL STEADILY CLIMB TOWARDS THE UPCOMING WEEKEND. THIS COMBINED WITH A JET POSITIONED FROM SOUTHWEST TO NORTHEAST FAVORS INCREASED CHANCES FOR CONVECTION IN THE LATER PERIODS OF THE EXTENDED. BEACHLER && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 08Z... * TIMING AND DURATION OF SHRA AND TSRA EARLY THIS MORNING. * ONGOING TS CHANCES THROUGH THE DAY. * CIG AND VIS TRENDS TO MVFR AND POSSIBLE IFR AS SHOWERS BECOME MORE WIDESPREAD. LENNING //DISCUSSION...UPDATED 06Z... PRIMARY CONCERN IS EVOLUTION OF THUNDERSTORM COMPLEX MOVING EAST OVERNIGHT. HAVE TIMED CORE OF NORTHERN PORTION OF COMPLEX TO PUSH INTO KRFD AREA BY AROUND 08Z...BUT THERE ARE CONVECTIVE SHOWERS BREAKING OUT AHEAD OF THIS AND MOVING NE...WHICH IS REFLECTED IN TAF. WANTED TO MONITOR CONVECTIVE TRENDS WITH SYSTEM BEFORE INCLUDING PREVAILING TSRA AT KRFD. WILL AMEND AS NEEDED. TIMED SHOWERS OUT AHEAD OF SYSTEM TO GET INTO EASTERN TERMINALS BETWEEN 830Z AND 930Z...BUT THIS IS A LOW CONFIDENCE FORECAST. QUESTION WILL THEN BECOME WHETHER TO INCLUDE ANYTHING MORE THAN VCTS FOR EASTERN TERMINALS AS WELL...BUT WILL ONCE AGAIN LIKE TO MONITOR CONVECTIVE TRENDS AND AMEND ACCORDINGLY. QUESTIONS ALSO AS TO DURATION OF SHRA/TSRA AT THE TERMINALS...WHICH IS LOW CONFIDENCE AT THIS TIME AND WILL NEED TO BE REFINED. OTHER ISSUES ARE SE WINDS OCCASIONALLY GUSTING UP TO AROUND 20 KT...BUT DID NOT THINK GUSTS WOULD BE FREQUENT ENOUGH TO INCLUDE AS PREVAILING. ONCE PRECIP STARTS TO WIND DOWN ON WEDNESDAY...POTENTIAL EXISTS FOR CIGS AND VSBY TO REALLY COME DOWN TO MVFR OR LOWER...SO HAVE CONTINUED TO TREND IN THIS DIRECTION. VSBY MORE LIKELY TO IMPROVE FIRST ON WEDNESDAY NIGHT ONCE WINDS TURN TO SWLY...BUT CIGS COULD STAY DOWN AT MVFR OR LOWER INTO THE OVERNIGHT HOURS TOMORROW NIGHT. RC //ORD AND MDW CONFIDENCE...UPDATED 08Z... * MEDIUM CONFIDENCE IN TIMING OF SHOWERS INTO TERMINALS. * MEDIUM CONFIDENCE IN TSRA COVERAGE AND DURATION. * LOW CONFIDENCE IN CIG AND VIS TRENDS. * HIGH CONFIDENCE IN WIND SPEED AND DIRECTION EXCEPT NEAR STORMS. LENNING //OUTLOOK FOR ORD/MDW FOR 12Z THURSDAY-12Z TUESDAY...UPDATED 00Z... * THURSDAY...VFR...SLIGHT CHANCE TSRA * FRIDAY...VFR...SLIGHT CHANCE TSRA * SATURDAY...VFR...CHANCE TSRA * SUNDAY...VFR...CHANCE TSRA * MONDAY...VFR...CHANCE TSRA SHEA && .MARINE... 1234 PM CDT HIGH PRESSURE OVER THE GREAT LAKES WILL WEAKEN AND DRIFT EAST TONIGHT AND WEDNESDAY AS A TROF OF LOW PRESSURE OVER THE PLAINS PIVOTS NORTHEAST TOWARD THE WESTERN LAKES. A TIGHTENING PRESSURE GRADIENT WILL RESULT IN INCREASING SOUTHEAST WINDS LATE TONIGHT INTO WEDNESDAY...MAINLY OVER THE SOUTH HALF OF THE LAKE. THE LOW PRESSURE WILL WEAKEN AS IT DRIFTS EAST ACROSS THE LAKES WEDNESDAY NIGHT AND THURSDAY. HIGH PRESSURE WILL BUILD BACK INTO THE WESTERN LAKES FOR THE END OF THE WEEK. ALLSOPP && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...NEARSHORE WINTHROP HARBOR TO NORTHERLY IS UNTIL 7 PM WEDNESDAY. &&
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
1214 AM CDT WED JUN 15 2011
ILZ003>006-008-010>014-019>023-032-033-039-INZ001-002-010-011-019-
160515-
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-
1214 AM CDT WED JUN 15 2011 /114 AM EDT WED JUN 15 2011/
THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH CENTRAL ILLINOIS...
NORTHEAST ILLINOIS AND NORTHWEST INDIANA.
.DAY ONE...OVERNIGHT.
WEATHER HAZARDS EXPECTED:
THUNDERSTORMS...SOME MAY PRODUCE:
HEAVY RAINFALL...WHICH MAY CAUSE LOCALIZED FLOODING.
CLOUD TO GROUND LIGHTNING.
AND PENNY SIZED HAIL.
AREAS AFFECTED AND TIMING:
THUNDERSTORMS WILL OVERSPREAD MUCH OF NORTHERN ILLINOIS FROM THE
WEST AND SOUTHWEST OVERNIGHT...POSSIBLY REACHING LAKE MICHIGAN
AND THE INDIANA BORDER TOWARD DAWN.
DISCUSSION:
A CLUSTER OF SHOWERS AND HEAVY THUNDERSTORMS ORGANIZING OVER
EASTERN IOWA AND WEST CENTRAL ILLINOIS LATE TUESDAY EVENING WILL
MOVE SLOWLY EASTWARD INTO NORTH CENTRAL AND EVENTUALLY NORTHEAST
ILLINOIS OVERNIGHT. THE THUNDERSTORMS WILL BE FEEDING ON A VERY
MOIST AIRMASS WEST OF THE AREA AND WILL BE MOVING RELATIVELY
SLOWLY...BOTH OF WHICH FAVOR THE POTENTIAL FOR HEAVY AND
POSSIBLY EXCESSIVE RAINFALL TOTALS WHICH COULD RESULT IN
LOCALIZED FLASH FLOODING. THE GREATEST THREAT OF HEAVY RAINFALL
AND FLASH FLOODING APPEARS TO BE SOUTHWEST OF A DIXON TO
KANKAKEE LINE. IN ADDITION TO HEAVY RAINFALL...THE MORE INTENSE
STORMS WILL ALSO POSE A THREAT OF HAIL UP TO THE SIZE OF PENNIES
AND FREQUENT CLOUD TO GROUND LIGHTNING.
PORTIONS OF THE KANKAKEE RIVER IN NORTHWEST INDIANA AND ILLINOIS
RIVER IN LA SALLE COUNTY WILL REMAIN IN FLOOD.
.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY.
SHOWERS AND EMBEDDED THUNDERSTORMS ARE LIKELY WEDNESDAY. LOCALLY
HEAVY RAINFALL WILL BE POSSIBLE WITH SOME STORMS.
SOILS REMAIN NEARLY SATURATED ACROSS THE OUTLOOK AREA...
WHICH COMBINED WITH LOCALLY HEAVY RAINFALL MAY RESULT
IN LOCALIZED FLOODING.
THERE IS A MODERATE RISK OF RIP CURRENTS AT ILLINOIS BEACHES
ALONG LAKE MICHIGAN WEDNESDAY.
PORTIONS OF THE KANKAKEE RIVER IN NORTHWEST INDIANA AND ILLINOIS
RIVER IN LA SALLE COUNTY WILL REMAIN IN FLOOD.
THERE WILL BE PERIODS OF THUNDERSTORMS FROM FRIDAY NIGHT THROUGH
TUESDAY INTERSPERSED WITH DRY PERIODS.
.SPOTTER INFORMATION STATEMENT...
SPOTTER ACTIVATION WILL NOT BE NECESSARY THROUGH TONIGHT.
&&
COMPLETE FORECAST INFORMATION IS AVAILABLE ON THE NWS CHICAGO
WEBPAGE: WEATHER.GOV/CHICAGO
LMZ740>745-160515-
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-
1214 AM CDT WED JUN 15 2011
THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE ILLINOIS NEARSHORE
WATERS OF LAKE MICHIGAN AND THE INDIANA NEARSHORE WATERS OF LAKE
MICHIGAN.
.DAY ONE...OVERNIGHT.
THERE IS A CHANCE OF THUNDERSTORMS TOWARD DAYBREAK WEDNESDAY.
WINDS AND WAVES HAZARDOUS TO SMALL CRAFT ARE EXPECTED FROM
NORTHERLY ISLAND TO WINTHROP HARBOR LATE TONIGHT.
.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY.
WINDS AND WAVES HAZARDOUS TO SMALL CRAFT ARE EXPECTED
FROM NORTHERLY ISLAND TO WINTHROP HARBOR THROUGH WEDNESDAY
EVENING.
SOME THUNDERSTORMS ARE LIKELY WEDNESDAY.
HERE WILL BE PERIODS OF THUNDERSTORMS FROM FRIDAY NIGHT THROUGH
TUESDAY INTERSPERSED WITH DRY PERIODS.
&&
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-
870-872-874-876-878-160515-
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-
1214 AM CDT WED JUN 15 2011
THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE OPEN WATERS OF LAKE
MICHIGAN.
.DAY ONE...OVERNIGHT.
THERE IS A CHANCE OF A THUNDERSTORM OVER FAR SOUTHERN PORTIONS OF
THE LAKE TOWARD DAYBREAK WEDNESDAY.
.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY.
SOME THUNDERSTORMS ARE LIKELY WEDNESDAY.
HERE WILL BE PERIODS OF THUNDERSTORMS FROM FRIDAY NIGHT THROUGH
TUESDAY INTERSPERSED WITH DRY PERIODS.
&&
COMPLETE FORECAST INFORMATION IS AVAILABLE ON THE NWS CHICAGO
WEBPAGE: WEATHER.GOV/CHICAGO
IZZIThe Lincoln radar (KILX), 96 km away, was scanning. The volume nearest the first event began at 08:18 UTC.
3 thunderstorm wind, 1 strong wind, 1 tornado. Local standard time, as filed.
Several tree limbs were knocked onto power lines and some large limbs fell onto the roads blocking traffic.
Multiple powerlines were reported down.
Multiple large tree limbs were reported down across the town of Watseka.
A large tree was blown down blocking portions of Route 12 near the intersection of Quentin Road causing damage to a wrought iron fence in Kildeer. Near Beach Park, numerous tree branches were blown down, and a portion of northbound Green Bay Road was blocked by a large branch. Winds gusting to 54 mph and 45 mph were measured in Libertyville and Waukegan, respectively.
The tornado began at approximately 518 PM CST at the Bishop Ford Expressway north of 159th Street. The tornado ended at 520 PM CST near the intersection of 158th Place and Paxton Avenue. It had a path length of 0.8 miles and a width of about 20 yards. The tornado was rated EF0 with winds 65 to 85 mph. The first signs of damage were at the Brown Meat Packing Company on Dutch Valley Road. The tornado caused damage to the roof of the meat packing plant. A 40 foot by 60 foot section of roofing was torn off and pieces of the roof were thrown 150 to 250 feet to the left of the tornado path, indicating rotation. An air conditioning unit was flipped and roof debris damaged a brick parapet. There was damage to a few shingles at the Sand Ridge Apartments on 158th Place. A few small tree limbs were also damaged. Debris from the roof of the plant also fell around the apartment complex.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Illinois in 2011Every state in 2011This day in weather historyThe tornado archive for Illinois, 2011Warnings in Illinois, June 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: 322099, 322100, 322101, 322105, 322104.