Thunderstorms moved across northern Illinois during the early morning hours of March 22nd. Some of the stronger storms produced severe hail.
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.
Thunderstorms moved across northern Illinois during the early morning hours of March 22nd. Some of the stronger storms produced severe hail.
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 Mar 22, 2:30 AM CST, 10 minutes earlier.
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
330 AM CDT THU MAR 22 2007
.DISCUSSION FOR AFTERNOON ZONES/GRIDS...
330 AM CDT
MAIN FORECAST CONCERN WILL BE ON CONVECTION MAINLY THIS
MORNING...AND THEN CONTINUED CHANCES OF SHOWERS/THUNDERSTORMS FROM
LATER TONIGHT THROUGH THE WEEKEND AND THE POTENTIAL FOR HEAVY
RAINFALL AND CONTINUED FLOOD POTENTIAL. APOLOGIES FOR AN ABBREVIATED
DISCUSSION DUE TO INCREASING CONVECTION ACROSS THE AREA THIS MORNING.
SURFACE COLD FRONT IS NOW APPROACHING THE MISSISSPPI RIVER WITH SPC
RUC MESOSCALE ANALYSIS GRAPHICS INDICATING BETWEEN 500-1000 J/KG OF
ELEVATED INSTABILITY IN CLOSE PROXMITY TO THE SFC FRONT WHERE LOW
LEVEL DEW POINT POOLING IS OCCURRING. EXPECTING INCREASE COVERAGE OF
SHOWERS AND THUNDERSTORMS THIS MORNING WITH APPROACH OF THIS
INSTABILITY AXIS AND ALSO INCREASING UPPER SUPPORT TOWARD 12Z AS
NORTHERN STREAM VORT MAX PUSHES INTO THE NORTHERN GREAT LAKES AND AS
UPPER JET STREAK CUTS THROUGH THE BASE OF THIS TROUGH INTO THE MID
MISSISSIPPI RIVER VALLEY. FRONT WILL RAPIDLY MOVE ACROSS THE CWA
TODAY...AND BY LATE MORNING ANY REMAINING SHOWERS/THUNDERSTORMS
SHOULD BE CONFINED TO FAR SOUTHEASTERN SECTIONS OF THE CWA. GIVEN
INSTABILITY AND INCREASING SHEAR NEAR THE FRONTAL BOUNDARY...WILL
HAVE TO MONITOR FOR WIND/HAIL THREAT FOR FIRST FEW HOURS THIS
MORNING. FAST MOVING NATURE OF STORMS SHOULD KEEP RAINFALL TOTALS
UNDER CONTROL BUT COMBINATION OF ADDITIONAL RAINFALL AND RAIN OF
PREVIOUS AFTERNOON MAY LEAD TO SOME MINOR FLOODING PROBLEMS THIS
MORNING.
HAVE MADE SOME REVISIONS TO THE FORECAST TONIGHT INTO FRIDAY...WITH
LATEST MODEL RUNS COMING INTO BETTER AGREEMENT IN A MORE NORTHERLY
POSITION OF SFC FRONTAL BOUNDARY AND BETTER CHANCES OF PERIODIC
EPISODES OF SHOWERS/THUNDERSTORMS...ESPECIALLY SOUTH OF INTERSTATE
80 WHERE ISENTROPIC LIFT WILL BE MORE PRONOUNCED. ALREADY HIGH RIVER
LEVELS WILL HAVE TO BE MONITOR FOR ADDITONAL FLOODING GIVEN. WILL
REINTRODUCE LIKELY POPS FOR TSRA ACROSS SOUTHERN AREAS LATE
TONIGHT...AND LIKELY SHOWERS AS FAR NORTH AS INTERSTATE
88...TAPERING TO CHANCE POPS FAR NORTH. ALSO INCREASED POPS FOR
FRIDAY WITH BOUNDARY STILL IN THE AREA.
LITTLE CHANGES MADE TO THE REMAINDER OF THE FORECAST.
MARSILI
&&
.AVIATION...
1254 AM CDT
VIGOROUS S/WV TROF PROPAGATING ACROSS NRN PLAINS AND UPPER MIDWEST
EARLY THIS MORNING...WITH ASSOCIATED SFC TROF/COLD FRONT FROM NRN WI
TO ERN IA AT 05Z. REGIONAL PROFILER DATA...AND 0445Z ACARS SOUNDING
OUT OF KRFD INDICATE 55 KT SOUTHWESTERLY LLJ IN 930-850 HPA LAYER
AHEAD OF LOW LEVEL TROF/FRONT. SOUNDING ALSO INDICATES STEEP LAPSE
RATES IN THIS LAYER...THOUGH A BIT OF A CAP NOTED AROUND 670 MB.
ISOLATED WEAK ELEVATED CONVECTIVE CELLS HAVE BEEN TRYING TO INITIATE
IN THIS REGION OF MOIST/WAA ACROSS FAR NRN IL...THOUGH APPEARS THEY
ARE FIGHTING CAP. NAM FCST SOUNDINGS DEPICT COOLING OF MID/UPR LVLS
WITH APPROACH OF S/WV EARLY THIS MORNING HOWEVER...WITH ELEVATED
CAPE INCREASING TO 550-650 J/KG FOR PARCELS BASED 875-900 HPA. THIS
ALONG WITH INCREASING LLVL CONVERGENCE AHEAD OF FRONT SHOULD BE
SUFFICIENT TO RESULT IN SCATTERED TRW AS BOUNDARY ADVANCES ACROSS
FCST IL. CURRENT REGIONAL RADAR TRENDS INDICATE STRONG CONVECTION IN
SWRN WI AND SRN IA...WITH SOME INCREASE IN CELL DEVELOPMENT ACROSS
ERN IA. GIVEN STRONG FAIRLY UNIDIRECTIONAL WIND FIELD MAY SEE SOME
GUSTS IN 40 KT RANGE WITH TSTMS...AND PERHAPS SOME SMALL HAIL GIVEN
MARGINAL CAPE PROFILES. THUS WILL MAINTAIN TS IN TERMINALS THIS
MORNING...MAINLY DURG 09-13Z PERIOD FROM WEST TO EAST AS FRONT MOVES
THRU. MAY SEE BRIEF PERIOD OF MVFR CIGS IN FRONTAL ZONE...THOUGH
STRONG LLVL DRYING BEHIND FRONT SHOULD DECREASE CLOUDS FAIRLY
RAPIDLY WITH VFR CONDITIONS PREVAILING WITHIN A FEW HOURS OF SUNRISE.
STRONG SW LLVL WIND FIELD IN TIGHT PRES GRADIENT AHEAD OF COLD FRONT
RESULTING IN GUSTY 20-30 KT WINDS ATTM. WILL SEE GRADIENT DECREASE
JUST A BIT WITHIN TROF AXIS TOWARD SUNRISE...THEN WSHFT TO NWLY
DIRECTION. SOME GUSTINESS AS SFC PRES RISE BUILDS IN EARLY
MORNING...THEN DECREASING WINDS THIS AFTN AS WEAK SFC HIGH BUILDS
IN. DVLPMNT OF NE WINDS OFF LAKE A GOOD PROBABILITY VERY LATE
AFTN/EARLY EVE AS GRADIENT WINDS DECREASE. NEXT S/WV AND ELEVATED
PCPN THREAT BEYOND 06Z TONIGHT...MORE ON THAT WITH NEXT FCST
ISSUANCE.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
.IL...NONE.
.IN...NONE.
.LM...SMALL CRAFT ADVISORY ILLINOIS NEARSHORE THROUGH 18Z THURS.
SMALL CRAFT ADVISORY INDIANA NEARSHORE 18Z WED-18Z THURS.
&&HAZARDOUS WEATHER OUTLOOK...UPDATED NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL 915 PM CDT WED MAR 21 2007 ILZ003>006-008-010>014-019>022-023-032-033-039-INZ001-002-010-011- 019-220930- WINNEBAGO-BOONE-MCHENRY-LAKE IL-OGLE-LEE-DE KALB-KANE-DU PAGE-COOK- LA SALLE-KENDALL-GRUNDY-WILL-KANKAKEE-LIVINGSTON-IROQUOIS-FORD- LAKE IN-PORTER-NEWTON-JASPER-BENTON- 915 PM CDT WED MAR 21 2007 THIS PORTION OF THE HAZARDOUS WEATHER OUTLOOK IS FOR NORTH CENTRAL AND NORTHEAST ILLINOIS...AND NORTHWEST INDIANA. .DAY ONE... OVERNIGHT THUNDERSTORMS ARE EXPECTED TO DEVELOP ACROSS NORTHWEST ILLINOIS AFTER MIDNIGHT...THEN MOVE EAST ACROSS NORTHERN ILLINOIS THROUGH DAWN. SEVERE WEATHER IS NOT EXPECTED. HOWEVER...SMALL HAIL...AND VERY HEAVY RAIN WILL BE POSSIBLE. SOME AREAS HAVE ALREADY RECEIVED ONE TO TWO INCHES OF RAINFALL IN THE PAST 24 HOURS. AN ADDITIONAL INCH OF RAINFALL IS POSSIBLE THROUGH MIDDAY THURSDAY. MANY STREAMS...CREEKS...AND RIVERS ARE AT OR NEAR BANKFULL WITH MINOR FLOODING FORECAST ON SOME RIVERS. ADDITIONAL RAINFALL OVERNIGHT INTO THURSDAY MAY CAUSE FURTHER RISES AND LOCALIZED FLOODING. .DAYS TWO THROUGH SEVEN... THURSDAY THROUGH TUESDAY THUNDERSTORMS WILL BE CONTINUING THURSDAY MORNING. BY LATE MORNING THE THUNDERSTORMS ARE EXPECTED MAINLY SOUTH OF INTERSTATE 80. SEVERE WEATHER IS NOT EXPECTED THURSDAY...BUT LOCALLY HEAVY RAINFALL WILL REMAIN POSSIBLE. HIGH WATER LEVELS ON AREA RIVERS COMBINED WITH THE NEW RAINFALL MAY LEAD TO MINOR FLOODING PROBLEMS ON AREA STREAMS AND RIVERS. .SPOTTER INFORMATION STATEMENT... SPOTTER REPORTS OF RAINFALL AND FLOODING WILL BE APPRECIATED OVERNIGHT AND THURSDAY. && COMPLETE FORECAST INFORMATION IS AVAILABLE ON THE NWS CHICAGO WEBPAGE: WEATHER.GOV/CHICAGO (LOWER CASE) LMZ740>745-766-220930- WINTHROP HARBOR IL TO MICHIGAN CITY IN- LAKE MICHIGAN- 915 PM CDT WED MAR 21 2007 THIS PORTION OF THE HAZARDOUS WEATHER OUTLOOK IS FOR THE ILLINOIS AND INDIANA WATERS OF LAKE MICHIGAN. .DAY ONE... OVERNIGHT A SMALL CRAFT ADVISORY IS IN EFFECT FOR THE NEARSHORE WATERS. THUNDERSTORMS WILL BE POSSIBLE ACROSS SOUTHERN LAKE MICHIGAN TONIGHT. A FEW THUNDERSTORMS MAY BECOME SEVERE. THE MAIN THREATS WILL BE LARGE HAIL AND DAMAGING WINDS. .DAYS TWO THROUGH SEVEN... THURSDAY THROUGH TUESDAY A SMALL CRAFT ADVISORY WILL REMAIN IN EFFECT FOR ALL OF THE NEARSHORE WATERS THROUGH EARLY THURSDAY AFTERNOON. SHOWERS AND THUNDERSTORMS ARE EXPECTED ACROSS SOUTHERN LAKE MICHIGAN THURSDAY MORNING. WIND GUSTS IN EXCESS OF 35 KNOTS ARE POSSIBLE EARLY THURSDAY MORNING WITH THE THUNDERSTORMS. && COMPLETE FORECAST INFORMATION IS AVAILABLE ON THE NWS CHICAGO WEBPAGE: WEATHER.GOV/CHICAGO (LOWER CASE)
PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
1000 PM CDT WED MAR 21 2007
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0407 PM HAIL ASHTON 41.87N 89.22W
03/21/2007 E0.75 INCH LEE IL PUBLIC
PENNY SIZE WITH SOME LARGER STONES.
0415 PM FLOOD LIBERTYVILLE 42.28N 87.97W
03/21/2007 LAKE IL EMERGENCY MNGR
8 TO 12 INCH STANDING WATER ON IL-176, 1/8 MILE WEST OF
ST MARYS RD.
0428 PM HAIL S POLO 41.98N 89.58W
03/21/2007 E0.88 INCH OGLE IL EMERGENCY MNGR
MARBLE TO NICKEL SIZE HAIL SOUTH OF TOWN ALONG IL26 AND
US52.
0436 PM FLOOD LIBERTYVILLE 42.28N 87.97W
03/21/2007 LAKE IL EMERGENCY MNGR
APPROX 6 INCHES OF STANDING WATER ON BRADLEY RD AT I-94
0438 PM HAIL DE KALB 41.93N 88.75W
03/21/2007 E0.25 INCH DE KALB IL TRAINED SPOTTER
PEA SIZE ON NIU CAMPUS.
0443 PM HAIL DE KALB 41.93N 88.75W
03/21/2007 E0.25 INCH DE KALB IL TRAINED SPOTTER
PEA TO DIME SIZE HAIL AT SYCAMORE RD AND BARBER GREEN RD.
0448 PM HAIL SYCAMORE 41.98N 88.70W
03/21/2007 E1.00 INCH DE KALB IL PUBLIC
QUARTER SIZE HAIL.
0455 PM FLOOD DE KALB 41.93N 88.75W
03/21/2007 DE KALB IL TRAINED SPOTTER
HEAVY RAIN FALL. APPROX ONE INCH IN 30 MINUTES. FLOODING
ON WEST SIDE OF NIU CAMPUS. WATER UP TO BOTTOM OF CAR
DOORS.
0503 PM HAIL STREAMWOOD 42.02N 88.17W
03/21/2007 E0.88 INCH COOK IL PUBLIC
NICKEL SIZE HAIL REPORT FROM COCORAHS.
0512 PM HAIL BYRON 42.13N 89.26W
03/21/2007 E0.75 INCH OGLE IL BROADCAST MEDIA
PENNY SIZE HAIL.
0515 PM HEAVY RAIN ARLINGTON HEIGHTS 42.09N 87.98W
03/21/2007 E1.00 INCH COOK IL TRAINED SPOTTER
ONE INCH OF RAIN IN A COUPLE OF HOURS.
0609 PM TSTM WND GST ISLAND LAKE 42.28N 88.20W
03/21/2007 E60.00 MPH MCHENRY IL TRAINED SPOTTER
IL-176 AND RIVER RD.
0659 PM HAIL MUNDELEIN 42.27N 88.00W
03/21/2007 E0.50 INCH LAKE IL TRAINED SPOTTER
MARBLE SIZE HAIL NEAR HAWLEY RD AND PERSHING RD.
0710 PM HAIL LAKE BLUFF 42.28N 87.85W
03/21/2007 E0.88 INCH LAKE IL AMATEUR RADIO
NICKEL SIZE HAIL AT IL-176 AND ROCKLAND ED.
&&
OTHER REPOERTS MAY BE ADDED IF/WHEN RECEIVED.
WNThe Chicago radar (KLOT), 47 km away, was scanning. The volume nearest the first event began at 08:40 UTC.
5 hail. Local standard time, as filed.
Golfball size hail occurred for several minutes and dented some cars.
Quarter size hail was reported at the intersection of Canton Farm Road and Wesmere Parkway.
Quarter size hail reported at Gaylord and Renwick.
Penny size hail was reported at the National Weather Service office in Romeoville.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Illinois in 2007Every state in 2007This day in weather historyWarnings in Illinois, March 2007
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: 21014, 21015, 21016, 21017, 21018.