Alert archive / Illinois / Severe Thunderstorm Warnings in 2015

Severe Thunderstorm Warning 121, NWS Chicago, IL

August 2, 2015Lake County, McHenry County, Illinois

NWS Chicago, IL issued this severe thunderstorm warning at Aug 2, 2015, 9:11 PM CDT for Lake County, McHenry County, Illinois. It was in force for 64 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Aug 2, 2015, 9:11 PM CDT (02:11 UTC)
Expired
Aug 2, 2015, 10:15 PM CDT
In force
64 min
Issued by
NWS Chicago, IL
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Lake County, IL, McHenry County, IL

The radar

The Milwaukee radar (KMKX), 77 km from the middle of the area, began a volume at 02:10 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Aug 2, 8:30 PM CDTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 2.2 hours before the alert went out and 209 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Davenport, at 00:00Z on 2015-08-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3927 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Davenport, at 00:00Z on 2015-08-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 167 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
3927 J/kg
Mixed-layer CIN
-12 J/kg
Mixed-layer LCL
1284 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
167 m²/s²
0-3 km storm-relative helicity
181 m²/s²
Significant tornado parameter
1.9
Supercell composite
16.8

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, 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 this severe thunderstorm warning went out at Aug 2, 6:55 PM CDT, 2 hours 16 minutes earlier.

Area forecast discussion, Aug 2, 6:55 PM CDT, 2 hours 16 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
655 PM CDT SUN AUG 2 2015

.MESOSCALE DISCUSSION...
620 PM CDT

WE CONTINUE TO MONITOR SEVERE STORM POTENTIAL FOR THIS EVENING.
LATEST HAND ANALYSIS INDICATED AN ANOMALOUSLY DEEP LOW AT 998 MB
NEAR SHEBOYGAN WI MOVING SOUTHEAST WITH A COLD FRONT/AXIS OF
CONVERGENCE EXTENDING BACK TO THE SOUTHWEST. THIS FRONT HAS SOME
ACCAS AND SOME CU ALONG IT IN EASTERN IA AND SOUTHERN WI...WITH
CONVECTION BACK IN SOUTHERN IA AS WELL. SO CANNOT RULE OUT A STORM
OR TWO GOING NOT FAR NORTHWEST OF ROCKFORD IN THE NEXT 60-90
MINUTES...ALTHOUGH MAIN FOCUS IS LIKELY WITH STORMS IN EASTERN
WISCONSIN AND PROGRESSION OF OR DEVELOP OFF OF THESE. SOUTHWEST
WINDS GUSTING TO 25-35 MPH IN THE NORTHERN END OF THE WARM SECTOR
LIKELY WILL DROP OFF SOME EARLY THIS EVENING...ALTHOUGH PRESSURE
FALLS WILL SUPPORT A CONTINUED DRAW OF LOW-MID 70S DEW POINTS
AHEAD OF THE FRONT.

HOW MUCH THE STORMS FILL IN ALONG THE BOUNDARY IS SOMEWHAT
UNCERTAIN GIVEN THE CAP STILL PRESENT ON ASCENDING 00Z DVN
WEATHER BALLOON...WITH ABOUT A 1C CAP ROUGHLY 600 FT DEEP NEAR
830MB. HOWEVER...AT LEAST SOME STORM DEVELOPMENT FURTHER WEST-
SOUTHWEST OF ONGOING ACTIVITY IN EASTERN WI IS LIKELY GIVEN THE
FORCING FROM INCOMING UPPER WAVE AND THE AFOREMENTIONED LOW-LEVEL
AIR MASS. THIS IS SUPPORTED BY MOST CONVECTIVE ALLOWING MODELS
/CAMS/...ESPECIALLY THE THEME OF FAR NORTHEAST ILLINOIS /INCLUDING
CHICAGO/ SEEING BETTER STORM COVERAGE IN THE 8-10 PM WINDOW. THE
SEGMENT OF STORMS IN EAST CENTRAL WISCONSIN HAVE PRODUCED OUTFLOW
THAT IF ABOUT 30 MILES AHEAD OF THEM...WHICH IS A BIT CONCERNING
THAT THEY MAY SHOW A GRADUAL WEAKENING. AT LEAST SOME STORM
DEVELOPMENT IS SEEN ON RADAR ALONG THIS OUTFLOW THOUGH. THIS
OUTFLOW...AS WELL AS ANY THAT MAY SURGE DOWN THE LAKE AND INTO
NEARSHORE AREAS OF SOUTHEAST WI AND NORTHEAST IL WOULD BE FAVORED
TO SUPPORT NEW STORM DEVELOPMENT AS WELL GIVEN THE LIMITED CAP IN
PLACE.

STEEP MID-LEVEL LAPSE RATES SUPPORTING HIGH CAPE WILL CONTINUE THE
LARGE HAIL THREAT IN THE STRONGEST OF STORMS THIS EVENING. ANY
SEGMENTS WILL BE CAPABLE OF SEVERE WINDS WITH STRONG AMBIENT
FLOW AND JUST THE BEHAVIOR SEEN ALREADY UPSTREAM AND LOCALLY IN
THE AREA FROM EARLIER STORM...AND THIS WILL LIKELY BE THE GREATER
THREAT AFTER SUNDOWN IF STORMS INDEED MOVE INTO NORTHEAST
IL/NORTHWEST IND.

MTF

&&

.SHORT TERM...
151 PM CDT

.THROUGH TONIGHT...

A FEW ISOLATED SHOWERS/STORMS ARE WORKING THERE WAY EASTWARD ACROSS THE
AREA. THESE STORMS ARE HOLDING TOGETHER TO SOME DEGREE AS
INSTABILITY IS FAVORABLE. THE STORM IN DEKALB COUNTY HAS PRODUCED
SOME HAIL OF NICKEL TO QUARTER SIZE. THIS STORM WILL CONTINUE TO
PROPAGATE SOUTHEASTWARD ALONG THE INTERSTATE 88 CORRIDOR. SHEAR IS
WEAKER CLOSER TO THE LAKE...SO A DOWNWARD TREND IS POSSIBLE...BUT
IT WILL LIKELY HOLD ITS OWN FOR A BIT LONGER. THERE IS QUITE A BIT
OF INTER-CLOUD LIGHTNING WITH THIS STORM...WITH OCCASIONAL/FREQUENT
CLOUD TO GROUND LIGHTNING AS WELL.

WE DO STILL EXPECT AFTERNOON ACTIVITY TO REMAIN ISOLATED AS WATER VAPOR
IMAGERY SUGGESTS THE BETTER SHORTWAVE ENERGY IS PASSING THROUGH
CENTRAL ILLINOIS...AND EVEN MORE SO ACROSS WISCONSIN. STILL...WEAK
ENERGY IN THE NORTHWEST FLOW PATTERN KEEPS THE ISOLATED/WIDELY
SCATTERED STORM CHANCE IN PLACE IN AN UNCAPPED ATMOSPHERE. SHEAR
IS STILL LOW THIS AFTERNOON...SO THE SEVERE THREAT AT LEAST
THROUGH MID AFTERNOON APPEARS ON THE LOW SIDE...THOUGH THESE
STORMS COULD LOCALLY ENHANCE THE ALREADY SYNOPTICALLY MODEST WIND
FIELD AND MAY HAVE SOME MARGINALLY SEVERE HAIL.

FOR THE REST OF THE AREA...JUST WARM AND BREEZY CONDITIONS REMAIN
IN PLACE ACROSS THE AREA AND READINGS IN UPPER 80S/LOW 90S.
AFTERNOON MIXING IS KEEPING DEWPOINTS FROM GETTING OUT OF THE LOW
TO MID 60S...EXCEPT IN FAVORED OUTLYING AREAS WHERE AIDED
EVAPOTRANSPIRATION LOCALLY ENHANCES THE MOISTURE READINGS.

MORE ORGANIZED THUNDERSTORMS ARE EXPECTED TO SPREAD SOUTH AND EASTWARD
TOWARD THE AREA AHEAD OF BETTER HEIGHT FALLS AND A MODEST COLD
FRONT. STILL SOME CONCERNS OVER HOW WIDESPREAD THE CONVECTIVE
COVERAGE WILL BE THIS EVENING. BEST FORCING IS TIED TO THE COLD
FRONT WHICH WILL BE COMING THROUGH THE AREA JUST AFTER PEAK
HEATING TIME. FOR STORMS THAT DO FORM...AMPLE SHEAR AND
INSTABILITY WILL BE PRESENT FOR STORMS TO QUICKLY BECOME
SEVERE...AND OUTFLOW BOUNDARIES FROM STORMS TO OUR NORTH COUPLED
WITH THE COLD FRONTAL PUSH WILL COMPLICATE MATTERS. AIDED
CONVERGENCE/LIFT CAN POTENTIALLY BE ENHANCED CLOSER TO THE LAKE
WHERE ADDITIONAL MOMENTUM MAY KEEP THE HIGHER CHANCES FOR STORMS
NORTH AND EAST CLOSER TO THE LAKE...AND POTENTIALLY IN OUR
SOUTHWEST ZONES WHERE DEWPOINTS/INSTABILITY MAY BE A LITTLE
HIGHER. CONVECTIVE ALLOWING MODELS PAINTING QUITE A RANGE OF
SOLUTIONS FROM A FORWARD PROPAGATING MCS IN OUR SOUTHWEST AREAS
AND VERY LITTLE CLOSER TO CHICAGO...WITH ALTERNATE SOLUTIONS
SUGGESTING THE FORMER SCENARIO WITH LAKE ADJACENT COUNTIES
FAVORED. THE COLD FRONT WILL PUSH SOUTHEASTWARD THROUGH THE AREA
TONIGHT...WITH THUNDERSTORMS EXITING TO THE SOUTHEAST.

KMD

&&

.LONG TERM...
344 PM CDT

MONDAY THROUGH SUNDAY...

PERIOD WILL BEGIN WITH SURFACE TROUGH/FRONTAL BOUNDARY DEPARTING
TO THE EAST...WITH ASSOCIATED PRECIP LIKEWISE DEPARTING TO THE
EAST. COOLER AND DRIER CONDITIONS STILL APPEAR LIKELY FOR THE
BEGINNING OF THIS UPCOMING WEEK AS LARGE UPPER LEVEL LOW SETTLES
INTO SOUTHERN CANADA AND THE NORTHEAST CONUS. NO PRECIP EXPECTED
MONDAY INTO TUESDAY...WITH TEMPS IN THE LOW 80S LIKELY BOTH DAYS.
MODELS QUICKLY DIVERGE WITH APPROACHING SYSTEM BY MIDWEEK...WITH
THE GFS THE OUTLIER BRINGING STRONGER/MORE DEFINED LOW CLOSER TO
THE CWA. THIS WOULD PROVIDE A FURTHER NORTHWARD PUSH OF PRECIP
AXIS ESPECIALLY DURING THE WEDNESDAY TIME FRAME. WITH UNCERTAINTY
IN PLACE AND WITH SOME GUIDANCE KEEPING THE CWA DRY...HAVE MADE
LITTLE CHANGES TO THE GOING FORECAST AND KEPT LOW CHANCE POPS FOR
THE SOUTHERN HALF OF THE CWA. AFTER THIS POSSIBLE PRECIP...A DRIER
TREND IS LOOKING LIKELY TOWARDS THE END OF THE WORK WEEK WHILE
BELOW NORMAL TEMPS OCCUR.

RODRIGUEZ

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 00Z...

* LINE OF TSRA THIS EVENING WITH HAIL AND STRONG WINDS POSSIBLE.

LENNING

//DISCUSSION...UPDATED 00Z...

FORECAST FOR THE EVENING REMAINS A BIT UNCERTAIN EVEN AT THIS
LATE HOUR. SATELLITE PICS SHOW A LINE OF CLOUDS DEVELOPING ALONG A
COLD FRONT ACROSS SRN WI AND DROPPING SOUTH. CONSIDERABLE
INSTABILITY AHEAD OF THIS FRONT ACROSS NORTHERN ILLINOIS WOULD BE
SUPPORTIVE OF WIDESPREAD TSRA ACTIVITY IF AND WHEN STORMS DO
MANAGE TO POP THROUGH A WEAK CAP. MOTION OF THE FRONT WOULD CARRY
THE ACTIVITY THROUGH FAIRLY RAPIDLY...WITH VFR AND W TO NW WINDS
IN ITS WAKE. TIMING AROUND 02Z INTO THE TERMINALS STILL LOOKS
REASONABLE...AND ALLOWS FOR POSSIBLE ISOLATED ACTIVITY BEFOREHAND
AND LINGERING SHOWERS FOR A SHORT WHILE AFTER.

LENNING

//ORD AND MDW CONFIDENCE...UPDATED 00Z...

* ONLY MEDIUM CONFIDENCE ON TIMING AND EXTENT OF TSRA THIS
  EVENING.

* HIGHER CONFIDENCE FOR ALL ELEMENTS OVERNIGHT AND TOMORROW.

LENNING

//OUTLOOK FOR ORD/MDW FOR 12Z TUESDAY-12Z SUNDAY...UPDATED 00Z...

TUESDAY...VFR. NORTHWEST WINDS.
WEDNESDAY...MAINLY VFR. CHANCE OF SHOWERS LATE.
THURSDAY...VFR. CHANCE OF SHRA/TSRA.
FRIDAY AND SATURDAY...VFR.

LENNING

&&

.MARINE...
440 PM CDT

STRONG SOUTHWEST WINDS WILL CONTINUE LATE THIS AFTERNOON INTO THE
EVENING ACROSS MUCH OF THE LAKE INCLUDING THE NEARSHORE AREAS...AS
STRONG LOW PRESSURE MOVES THROUGH THE GREAT LAKES REGION. HIGHEST
SPEEDS ARE OCCURRING ACROSS THE SOUTHERN HALF OF THE LAKE AND
ESPECIALLY ALONG THE NEARSHORE WHERE A FEW GALE FORCE GUSTS ARE
ALSO POSSIBLE. THIS WILL PERSIST BEFORE WINDS DIMINISH LATE THIS
EVENING AND INTO THE OVERNIGHT HOURS AS THIS LOW EXITS TO THE
EAST...WITH WINDS BECOMING MORE WEST NORTHWEST.

RODRIGUEZ

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...GALE WARNING...NEARSHORE WATERS UNTIL
     10 PM SUNDAY.

&&

VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)

FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Hazardous weather outlook, Aug 2, 4:28 PM CDT, 4 hours 43 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
428 PM CDT SUN AUG 2 2015

ILZ003>006-008-010>014-019>023-032-033-039-INZ001-002-010-011-019-
032130-
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-
428 PM CDT SUN AUG 2 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH CENTRAL ILLINOIS...
NORTHEAST ILLINOIS AND NORTHWEST INDIANA.

.DAY ONE...TONIGHT.

  WEATHER HAZARDS EXPECTED:

  THUNDERSTORMS...SOME CAPABLE OF PRODUCING:
	WIND GUSTS IN EXCESS OF 60 MPH.
    HAIL TO THE SIZE OF GOLF BALLS.
    FREQUENT CLOUD TO GROUND LIGHTNING.

  AREAS AFFECTED AND TIMING:
    THE ENTIRE OUTLOOK AREA MID TO LATE THIS EVENING.

  DISCUSSION:
A LINE OF THUNDERSTORMS IS EXPECTED TO DEVELOP ACROSS WISCONSIN
LATE THIS AFTERNOON AND MOVE SOUTHEAST REACHING NORTHERN ILLINOIS
AROUND 7 PM...AND THEN CONTINUE SOUTHEAST AFFECTING REMAINING
AREAS IN NORTHERN ILLINOIS AND NORTHWEST INDIANA THROUGH LATE THIS
EVENING. THUNDERSTORMS SHOULD BE PROGRESSING QUICKLY TO THE SOUTH
AND SOUTHEAST...WITH THUNDERSTORMS COMING TO AN END BEFORE
MIDNIGHT.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY.

THERE IS A CHANCE OF THUNDERSTORMS TUESDAY NIGHT THROUGH
THURSDAY...MAINLY SOUTH OF INTERSTATE 80.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS WILL LIKELY BE NEEDED THIS EVENING.

&&

LMZ740>745-032130-
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-
428 PM CDT SUN AUG 2 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE ILLINOIS NEARSHORE
WATERS OF LAKE MICHIGAN AND THE INDIANA NEARSHORE WATERS OF LAKE
MICHIGAN.

.DAY ONE...TONIGHT.

WINDS WILL LIKELY BE HAZARDOUS TO SMALL CRAFT THROUGH THIS
EVENING.

THUNDERSTORMS ARE LIKELY THIS EVENING. SOME OF THESE STORMS COULD
BE SEVERE WITH WIND GUSTS IN EXCESS OF 40 KT AND LARGE HAIL.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY.

WINDS AND WAVES HAZARDOUS TO SMALL CRAFT ARE POSSIBLE THURSDAY
EVENING THROUGH FRIDAY MORNING.

&&

LMZ080-261-362-364-366-563-565-567-669-671-673-675-777-779-868-
870-872-874-876-878-032130-
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-
428 PM CDT SUN AUG 2 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE OPEN WATERS OF LAKE
MICHIGAN.

.DAY ONE...TONIGHT.

THUNDERSTORMS ARE LIKELY THIS EVENING. SOME OF THESE STORMS COULD
BE SEVERE WITH WINDS IN EXCESS OF 40 KT AND LARGE HAIL.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

&&

RODRIGUEZ

VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)

FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/NWSCHICAGO
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO

In the hours before

Local storm report, Aug 2, 7:16 PM CDT, 1 hour 55 minutes before
PRELIMINARY LOCAL STORM REPORT...CORRECTED
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
716 PM CDT SUN AUG 02 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0235 PM     TSTM WND DMG     WOOD DALE               41.97N 87.98W
08/02/2015                   DUPAGE             IL   OTHER FEDERAL

            *** 1 FATAL, 3 INJ *** TENT COLLAPSE OCCURRED AT WOOD
            DALE PRAIRIE FEST AT WOOD DALE JUNIOR HIGH SCHOOL.
            BESIDES THE ONE FATALITY...THREE INJURIES WERE SERIOUS
            AND MORE PEOPLE WERE TRANSPORTED TO HOSPITALS. TIME
            ESTIMATED USING RADAR.

&&

MTF
Local storm report, Aug 2, 7:18 PM CDT, 1 hour 53 minutes before
PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
718 PM CDT SUN AUG 02 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0141 PM     HAIL             3 SW DE KALB            41.90N 88.78W
08/02/2015  E1.00 INCH       DE KALB            IL   TRAINED SPOTTER

0154 PM     HAIL             1 S DE KALB             41.92N 88.75W
08/02/2015  E1.25 INCH       DE KALB            IL   TRAINED SPOTTER

            ANNIE GLIDDEN ROAD

0201 PM     HAIL             MAPLE PARK              41.91N 88.59W
08/02/2015  M1.00 INCH       KANE               IL   PUBLIC

0205 PM     HAIL             ELBURN                  41.89N 88.47W
08/02/2015  E1.00 INCH       KANE               IL   CO-OP OBSERVER

            HAIL SIZE FROM DIME TO QUARTER SIZE OVER THE LAST 7 TO 8
            MINUTES WITH HEAVY RAINFALL.

0216 PM     HAIL             ST. CHARLES             41.92N 88.30W
08/02/2015  M1.00 INCH       KANE               IL   TRAINED SPOTTER

0217 PM     HAIL             WAYNE                   41.95N 88.26W
08/02/2015  E1.50 INCH       DUPAGE             IL   PUBLIC

0220 PM     HAIL             5 NW CAROL STREAM       41.96N 88.20W
08/02/2015  M1.50 INCH       DUPAGE             IL   COCORAHS

0223 PM     HAIL             CAROL STREAM            41.92N 88.13W
08/02/2015  E1.00 INCH       DUPAGE             IL   TRAINED SPOTTER

            LASTED 2 MINUTES

0225 PM     HAIL             ROSELLE                 41.98N 88.08W
08/02/2015  E1.00 INCH       DUPAGE             IL   TRAINED SPOTTER

0228 PM     HAIL             BLOOMINGDALE            41.95N 88.09W
08/02/2015  E1.00 INCH       DUPAGE             IL   PUBLIC

0229 PM     HAIL             ROSELLE                 41.98N 88.08W
08/02/2015  M1.75 INCH       DUPAGE             IL   PUBLIC

0235 PM     TSTM WND DMG     WOOD DALE               41.97N 87.98W
08/02/2015                   DUPAGE             IL   OTHER FEDERAL

            *** 1 FATAL, 3 INJ *** TENT COLLAPSE OCCURRED AT WOOD
            DALE PRAIRIE FEST AT WOOD DALE JUNIOR HIGH SCHOOL.
            BESIDES THE ONE FATALITY...THREE INJURIES WERE SERIOUS
            AND MORE PEOPLE WERE TRANSPORTED TO HOSPITALS. TIME
            ESTIMATED USING RADAR.

0240 PM     TSTM WND GST     OHARE AIRPORT           41.98N 87.90W
08/02/2015  M52.00 MPH       COOK               IL   ASOS

0240 PM     HAIL             5 SE DES PLAINES        41.98N 87.84W
08/02/2015  E0.88 INCH       COOK               IL   TRAINED SPOTTER

            DIME TO NICKEL SIZE HAIL AND CUMBERLAND AND BERYWN.

0242 PM     TSTM WND DMG     ROSEMONT                41.99N 87.87W
08/02/2015                   COOK               IL   EMERGENCY MNGR

            DOME PRACTICE FACILITY DAMAGED. TIME ESTIMATED USING
            RADAR.

0245 PM     HAIL             4 NW MONTROSE HARBOR    42.00N 87.70W
08/02/2015  E1.00 INCH       COOK               IL   COCORAHS

            STRONG WINDS AND HEAVY RAIN FALL.

0250 PM     HAIL             5 NNW LINCOLN PARK      42.00N 87.67W
08/02/2015  E1.00 INCH       COOK               IL   COCORAHS

0253 PM     HAIL             NW CHICAGO              41.88N 87.63W
08/02/2015  M1.00 INCH       COOK               IL   TRAINED SPOTTER

0253 PM     HAIL             EVANSTON                42.05N 87.69W
08/02/2015  E1.00 INCH       COOK               IL   TRAINED SPOTTER

            ALSO SMALL 1 INCH BRANCHES DOWN.

0255 PM     TSTM WND DMG     EVANSTON                42.05N 87.69W
08/02/2015                   COOK               IL   TRAINED SPOTTER

            SHERIDAN ROAD AND KEDZIE. 2.5 FOOT ROUND DIAMETER TREE 30
            FT TALL COMPLETELY UPROOTED. TIME ESTIMATED BASED ON
            RADAR.

0257 PM     TSTM WND DMG     3 S EVANSTON            42.01N 87.70W
08/02/2015                   COOK               IL   LAW ENFORCEMENT

            *** 1 INJ *** NUMEROUS LARGE TREES DOWN IN ROGERS PARK
            AREA. ONE MAN INJURED BY A FALLING TREE NEAR TOUHY AND
            KEDZIE.

0300 PM     TSTM WND GST     4 NE CHICAGO            41.92N 87.57W
08/02/2015  M43.00 MPH       LMZ741             IL   C-MAN STATION

&&

MTF
Special weather statement, Aug 2, 8:30 PM CDT, 41 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
830 PM CDT SUN AUG 2 2015

ILZ006-030215-
LAKE IL-
830 PM CDT SUN AUG 2 2015

...SPECIAL WEATHER STATEMENT FOR LAKE COUNTY UNTIL 915 PM CDT...

AT 829 PM CDT...DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM OVER
GRAYSLAKE...MOVING EAST AT 45 MPH.

DIME SIZE HAIL AND WINDS IN EXCESS OF 40 MPH WILL BE POSSIBLE WITH
THIS STORM.

IN ADDITION...MORE STORMS ARE LIKELY TO DEVELOP ACROSS LAKE COUNTY
AS WELL AS MOVE SOUTHWARD FROM WISCONSIN THROUGH 10 PM. THESE STORMS
COULD BECOME SEVERE.

LOCATIONS IMPACTED INCLUDE...
WAUKEGAN...            BUFFALO GROVE...       NORTH CHICAGO...
GURNEE...              MUNDELEIN...           HIGHLAND PARK...
VERNON HILLS...        ZION...                GRAYSLAKE...
LIBERTYVILLE...        LAKE ZURICH...         LAKE FOREST...
ROUND LAKE...          DEERFIELD...           ANTIOCH...
BEACH PARK...          WAUCONDA...            FOX LAKE...
LAKE VILLA...          GLENCOE...

INCLUDING THE FOLLOWING INTERSTATES...
 I-94 BETWEEN MILE MARKERS 1 AND 23.
 I-294 BETWEEN MILE MARKERS 1 AND 23.

THIS INCLUDES...
CHAIN O LAKES STATE PARK...COLLEGE OF LAKE COUNTY...GREAT LAKES NAVAL
TRAINING CENTER...IL BEACH STATE PARK...LAKE COUNTY FIELDERS
BASEBALL...LAKE COUNTY IL FAIRGROUNDS...LAKE FOREST COLLEGE...RAVINIA
MUSIC FESTIVAL...AND SIX FLAGS GREAT AMERICA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FREQUENT CLOUD TO GROUND LIGHTNING IS OCCURRING WITH THIS STORM.
LIGHTNING CAN STRIKE 15 MILES AWAY FROM A THUNDERSTORM. SEEK A SAFE
SHELTER INSIDE A BUILDING OR VEHICLE.

&&

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 200 AM CDT FOR
NORTHEASTERN ILLINOIS.

LAT...LON 4249 8780 4238 8781 4236 8782 4237 8782
      4233 8783 4231 8782 4230 8783 4229 8783
      4221 8780 4215 8776 4224 8820 4250 8820
TIME...MOT...LOC 0129Z 277DEG 37KT 4231 8804

MTF
Local storm report, Aug 2, 8:54 PM CDT, 17 minutes before
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Local storm report, Aug 2, 8:56 PM CDT, 15 minutes before
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Local storm report, Aug 2, 9:09 PM CDT, 2 minutes before
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The office that day

Everything else NWS Chicago, IL issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 2, 8:23 PM CDTSpecial Marine WarningLOT112 min
Aug 2, 8:30 PM CDTSpecial Weather StatementLOTLake45 min
Aug 2, 8:45 PM CDTTornado WarningLOTLake20 min
Aug 2, 9:42 PM CDTSevere Thunderstorm WarningLOTCook, Lake, McHenry63 min
Aug 2, 9:48 PM CDTSpecial Weather StatementLOTBoone42 min
Aug 2, 9:49 PM CDTSpecial Marine WarningLOT116 min
Aug 2, 10:00 PM CDTSpecial Weather StatementLOTCook, DuPage, Kane45 min
Aug 2, 10:13 PM CDTSpecial Marine WarningLOT92 min
Aug 2, 10:15 PM CDTSevere Thunderstorm WarningLOTCook, DuPage, Kane, McHenry45 min
Aug 2, 10:28 PM CDTSevere Thunderstorm WarningLOTCook32 min
Aug 2, 10:44 PM CDTSevere Thunderstorm WarningLOTCook31 min
Aug 2, 10:54 PM CDTSevere Thunderstorm WarningLOTCook, DuPage, Kane66 min
Aug 2, 11:00 PM CDTSevere Thunderstorm WarningLOTCook9 min
Aug 2, 11:22 PM CDTSevere Thunderstorm WarningLOTCook, DuPage, Kendall, Will53 min
Aug 2, 11:45 PM CDTSpecial Marine WarningLOT60 min
Aug 3, 12:28 AM CDTSpecial Weather StatementLOTKankakee47 min
Aug 2, 11:14 PM CDTSpecial Weather StatementLOTPorter31 min
Aug 3, 12:14 AM CDTSevere Thunderstorm WarningLOTJasper, Lake, Newton, Porter61 min

Nearby

Severe Thunderstorm Warnings in Illinois, 2015Every severe thunderstorm warning in 2015

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.