Alert archive / Illinois / Severe Thunderstorm Warnings in 2016

Severe Thunderstorm Warning 46, NWS Chicago, IL

July 6, 2016Cook County, Kankakee County, Will County, Illinois; Lake County, Porter County, Indiana

NWS Chicago, IL issued this severe thunderstorm warning at Jul 6, 2016, 3:38 AM CDT for Cook County, Kankakee County, Will County, Illinois; Lake County, Porter County, Indiana. It was in force for 54 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
Jul 6, 2016, 3:38 AM CDT (08:38 UTC)
Expired
Jul 6, 2016, 4:32 AM CDT
In force
54 min
Issued by
NWS Chicago, IL
Area
Storm-based polygon
Hail
0.75 in
Wind
70.0 mph

Counties Cook County, IL, Kankakee County, IL, Will County, IL, Lake County, IN, Porter County, IN

The radar

The Chicago radar (KLOT), 43 km from the middle of the area, began a volume at 08:41 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
Jul 6, 1:55 AM CDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 8.6 hours before the alert went out and 172 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, Lincoln, IL at 00:00Z on 2016-07-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 960 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, Lincoln, IL at 00:00Z on 2016-07-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 70 square meters per square second.1939Sfc1 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
960 J/kg
Mixed-layer CIN
-160 J/kg
Mixed-layer LCL
1184 m above ground
0-6 km bulk shear
12 kt
0-1 km storm-relative helicity
70 m²/s²
0-3 km storm-relative helicity
83 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

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 Jul 6, 3:15 AM CDT, 23 minutes earlier.

Area forecast discussion, Jul 6, 3:15 AM CDT, 23 minutes before
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Hazardous weather outlook, Jul 5, 6:33 PM CDT, 9 hours 5 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
633 PM CDT TUE JUL 5 2016

ILZ003>006-008-010>014-019>023-032-033-039-INZ001-002-010-011-019-
062345-
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-
633 PM CDT TUE JUL 5 2016 /733 PM EDT TUE JUL 5 2016/

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

.DAY ONE...TONIGHT.

WEATHER HAZARDS EXPECTED:
  SIGNIFICANT THUNDERSTORM RISK...WITH AN ASSOCIATED:
   LIMITED HAIL RISK...UP TO QUARTER SIZE.
   SIGNIFICANT THUNDERSTORM WIND DAMAGE RISK...IN EXCESS OF
   60 MPH.
   LIMITED FLASH FLOODING RISK.

DISCUSSION:

STRONG TO SEVERE THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER THE
UPPER MISSISSIPPI VALLEY THIS EVENING...AND QUICKLY MOVE
SOUTHEAST INTO NORTHERN ILLINOIS AROUND MIDNIGHT. THESE STORMS
WILL POSE A DAMAGING WIND THREAT AS THEY QUICKLY PUSH SOUTH
THROUGH THE OUTLOOK AREA THROUGH 6 AM CDT. THE HIGHER THREAT OF
SEVERE WEATHER IS EXPECTED TO BE MAINLY OVER PORTIONS OF NORTHERN
ILLINOIS TO THE NORTHWEST OF A PONTIAC TO CHICAGO LINE...THOUGH A
DAMAGING WIND RISK CANNOT BE RULED OUT SOUTHEAST OF THIS LINE.
LOCALLY HEAVY RAINFALL WILL BE POSSIBLE WITH THE STORMS AS WELL
AND THIS COULD LEAD TO LOCALIZED FLOODING.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY.

WEDNESDAY...
  LIMITED SEVERE THUNDERSTORM RISK.
  LIMITED EXCESSIVE HEAT RISK.
THURSDAY...
  ELEVATED SEVERE THUNDERSTORM RISK.
  LIMITED EXCESSIVE HEAT RISK.
FRIDAY...
  LIMITED THUNDERSTORM RISK.
  LIMITED EXCESSIVE HEAT RISK.
SATURDAY...
  HIGH SWIM RISK ALONG NORTHWEST INDIANA BEACHES.
SUNDAY AND MONDAY...
  LIMITED THUNDERSTORM RISK.

DISCUSSION:

UNSETTLED WEATHER WILL CONTINUE THROUGH EARLY FRIDAY...WITH
PERIODS OF SCATTERED THUNDERSTORMS POSSIBLE. THERE IS AN
ADDITIONAL THREAT OF SEVERE STORMS WEDNESDAY AFTERNOON AND EARLY
EVENING...AND AGAIN ON THURSDAY AND THURSDAY NIGHT.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS WILL LIKELY BE NEEDED OVERNIGHT TONIGHT MAINLY ACROSS
NORTHERN ILLINOIS.

GENERAL STORM MOTION OF THE DAY:

MOVING TO THE SOUTHEAST AT 40 MPH.

&&

LMZ740>745-062345-
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-
633 PM CDT TUE JUL 5 2016

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

.DAY ONE...TONIGHT.

THUNDERSTORMS ARE LIKELY TONIGHT.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY.

PERIODS OF SCATTERED THUNDERSTORMS ARE POSSIBLE WEDNESDAY
THROUGH EARLY FRIDAY. A FEW STORMS COULD BE SEVERE WEDNESDAY
AND AGAIN THURSDAY.

&&

LMZ080-261-362-364-366-563-565-567-669-671-673-675-777-779-868-
870-872-874-876-878-062345-
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-
633 PM CDT TUE JUL 5 2016

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

.DAY ONE...TONIGHT.

THUNDERSTORMS ARE LIKELY TONIGHT.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY.

PERIODS OF SCATTERED THUNDERSTORMS ARE POSSIBLE WEDNESDAY
THROUGH EARLY FRIDAY. A FEW STORMS COULD BE SEVERE WEDNESDAY
AND AGAIN THURSDAY.

&&

KJB

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

Special weather statement, Jul 6, 1:36 AM CDT, 2 hours 2 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
136 AM CDT WED JUL 6 2016

ILZ003>005-008-010-011-060715-
BOONE IL-OGLE IL-LEE IL-WINNEBAGO IL-DE KALB IL-MCHENRY IL-
136 AM CDT WED JUL 6 2016

...SPECIAL WEATHER STATEMENT FOR OGLE...SOUTHERN WINNEBAGO...
NORTHWESTERN DE KALB...NORTHWESTERN LEE...SOUTHERN BOONE AND
SOUTHWESTERN MCHENRY COUNTIES UNTIL 215 AM CDT...

AT 134 AM CDT...DOPPLER RADAR WAS TRACKING A LINE OF STRONG
THUNDERSTORMS ALONG A LINE EXTENDING FROM NEAR BYRON TO NEAR POLO...
AND MOVING SOUTHEAST AT 45 MPH.

WIND GUSTS OF 50 TO 55 MPH WILL BE POSSIBLE WITH THESE STORMS. IT IS
ALSO POSSIBLE THE STORMS COULD STRENGTHEN AND REQUIRE A WARNING.

LOCATIONS IMPACTED INCLUDE...
ROCKFORD...            BELVIDERE...           DIXON...
OREGON...              MOUNT MORRIS...        ROCKFORD AIRPORT...
BYRON...               CHERRY VALLEY...       WINNEBAGO...
POLO...                PECATONICA...          KIRKLAND...
FORRESTON...           STILLMAN VALLEY...     FRANKLIN GROVE...
DAVIS JUNCTION...      LEAF RIVER...          NELSON...
HARMON...              ADELINE...

INCLUDING THE FOLLOWING INTERSTATES...
 I-39 BETWEEN MILE MARKERS 104 AND 123.
 I-88 BETWEEN MILE MARKERS 45 AND 60.
 I-90 BETWEEN MILE MARKERS 45 AND 63.

THIS INCLUDES...  CASTLE ROCK STATE PARK...LOWDEN STATE PARK...OGLE
COUNTY FAIRGROUNDS...SAUK VALLEY COLLEGE...AND WHITE PINES STATE PARK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TORRENTIAL RAINFALL IS ALSO OCCURRING WITH THESE STORMS...AND MAY
LEAD TO FLASH FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED
ROADWAYS.

&&

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 500 AM CDT FOR
NORTH CENTRAL ILLINOIS.

LAT...LON 4209 8969 4220 8951 4220 8940 4227 8940
      4233 8931 4222 8859 4167 8963 4193 8963
      4193 8969
TIME...MOT...LOC 0634Z 295DEG 40KT 4216 8927 4203 8956

BIRK
Local storm report, Jul 6, 1:41 AM CDT, 1 hour 57 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
141 AM CDT WED JUL 06 2016

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

0136 AM     TSTM WND GST     ROCKFORD AIRPORT        42.20N 89.10W
07/06/2016  M46 MPH          WINNEBAGO          IL   ASOS

&&
Local storm report, Jul 6, 2:12 AM CDT, 1 hour 26 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
212 AM CDT WED JUL 06 2016

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

0200 AM     TSTM WND GST     CRYSTAL LAKE            42.23N 88.33W
07/06/2016  M55 MPH          MCHENRY            IL   AMATEUR RADIO

            ROUTE 14 AND NORTH RIDGEFIELD ROAD.

&&
Local storm report, Jul 6, 2:47 AM CDT, 51 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
247 AM CDT WED JUL 06 2016

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

0241 AM     TSTM WND GST     OHARE AIRPORT           41.98N 87.90W
07/06/2016  M51 MPH          COOK               IL   ASOS

&&
Special weather statement, Jul 6, 3:25 AM CDT, 13 minutes before
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The office that day

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

IssuedProductOfficeCountiesLasted
Jul 6, 1:20 AM CDTSevere Thunderstorm WarningLOTBoone, Lake, McHenry, Winnebago55 min
Jul 6, 1:36 AM CDTSpecial Weather StatementLOTOgle39 min
Jul 6, 1:42 AM CDTSpecial Marine WarningLOT2 hr
Jul 6, 1:50 AM CDTSevere Thunderstorm WarningLOTBoone, Cook, DeKalb, DuPage, Kane, Lake and 1 more70 min
Jul 6, 2:47 AM CDTSevere Thunderstorm WarningLOTCook, DuPage, Will58 min
Jul 6, 2:49 AM CDTSpecial Marine WarningLOT86 min
Jul 6, 3:25 AM CDTSpecial Weather StatementLOTWill35 min
Jul 6, 4:02 AM CDTSpecial Weather StatementLOTIroquois43 min

Nearby

Severe Thunderstorm Warnings in Illinois, 2016Severe Thunderstorm Warnings in Indiana, 2016Every severe thunderstorm warning in 2016

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.