Alert archive / Illinois / Flash Flood Warnings in 2015

Flash Flood Warning 15, NWS Chicago, IL

June 15, 20158 counties in Illinois; Lake County, Indiana

NWS Chicago, IL issued this flash flood warning at Jun 15, 2015, 6:09 PM CDT for 8 counties in Illinois; Lake County, Indiana. It was in force for 4 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jun 15, 2015, 6:09 PM CDT (23:09 UTC)
Expired: Jun 15, 2015, 10:30 PM CDT
In force: 4 hr
Issued by: NWS Chicago, IL
Area: Storm-based polygon
Flood severity: None

Counties Cook County, IL, DeKalb County, IL, DuPage County, IL, Grundy County, IL, Kendall County, IL, LaSalle County, IL, Lee County, IL, Will County, IL, Lake County, IN

The radar

The Chicago radar (KLOT), 20 km from the middle of the area, began a volume at 23:10 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 nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 11.2 hours before the alert went out and 164 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 260 J/kg
Mixed-layer CIN: -63 J/kg
Mixed-layer LCL: 907 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: 4 m²/s²
0-3 km storm-relative helicity: 30 m²/s²
Significant tornado parameter: -0.0
Supercell composite: -0.1

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood 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 flash flood warning went out at Jun 15, 4:55 PM CDT, 1 hour 14 minutes earlier.

Area forecast discussion, Jun 15, 4:55 PM CDT, 1 hour 14 minutes before

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

Hazardous weather outlook, Jun 15, 3:39 PM CDT, 2 hours 30 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
339 PM CDT MON JUN 15 2015

ILZ003>006-008-010>014-019>023-032-033-039-INZ001-002-010-011-019-
162045-
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-
339 PM CDT MON JUN 15 2015

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

.DAY ONE...TONIGHT.

  WEATHER HAZARDS EXPECTED:

  THUNDERSTORMS...SOME OF WHICH MAY PRODUCE:

   FREQUENT CLOUD TO GROUND LIGHTNING.
   VERY HEAVY RAINFALL AND FLASH FLOODING.
   ISOLATED WINDS GUSTS ABOVE 60 MPH.

  AREAS AFFECTED AND TIMING:

   SCATTERED THUNDERSTORMS WILL LIKELY GROW MORE NUMEROUS ACROSS
   THE OUTLOOK AREA THROUGH THIS EVENING. THE MAIN CONCENTRATION
   OF THUNDERSTORMS WILL GRADUALLY SHIFT SOUTH OVERNIGHT AND
   END NORTH OF INTERSTATE 80 DURING THE PRE-DAWN HOURS.

  DISCUSSION:

   THUNDERSTORMS WILL BECOME MORE NUMEROUS THROUGH THE EVENING AS
   A SLOW MOVING FRONT APPROACHES THE AREA. THE ATMOSPHERE IS
   EXTREMELY MOIST AND ANY STORMS THAT FORM WILL HAVE THE
   POTENTIAL TO PRODUCE TORRENTIAL DOWNPOURS...POTENTIALLY
   UPWARDS OF 2 INCHES IN AN HOUR OR LESS. IN ADDITION TO THE
   HEAVY RAIN...WHICH MAY RESULT IN LOCALIZED FLASH FLOODING...A
   COUPLE OF THE STORMS COULD PRODUCE LOCALIZED WIND GUSTS OVER
   60 MPH.

  IN ADDITION...PORTIONS OF THE IROQUOIS...KANKAKEE...AND
  ILLINOIS RIVERS WILL REMAIN IN FLOOD.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY.

THERE WILL BE PERIODIC CHANCES OF THUNDERSTORMS TUESDAY THROUGH
THE WEEKEND.

PORTIONS OF THE IROQUOIS...KANKAKEE...AND ILLINOIS RIVERS WILL
REMAIN IN FLOOD.

.SPOTTER INFORMATION STATEMENT...

DUE TO THE ISOLATED NATURE OF THE SEVERE WEATHER THREAT...SPOTTER
ACTIVATION IS NOT ANTICIPATED THROUGH TONIGHT...HOWEVER ANY
OBSERVATIONS OF FLOODING OR MEASURED HEAVY RAIN TOTALS WOULD BE
APPRECIATED.

&&

LMZ740>745-162045-
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-
339 PM CDT MON JUN 15 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.

PERIODS OF THUNDERSTORMS ARE EXPECTED THROUGH LATE TONIGHT. SOME
OF THE STORMS MAY PRODUCE GUSTS UP TO 35 KNOTS.

AREAS OF FOG ARE POSSIBLE THROUGH THIS EVENING.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY.

THERE ARE PERIODIC CHANCES OF THUNDERSTORMS LATE TUESDAY NIGHT
THROUGH THE WEEKEND.

&&

LMZ080-261-362-364-366-563-565-567-669-671-673-675-777-779-868-
870-872-874-876-878-162045-
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-
339 PM CDT MON JUN 15 2015

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

.DAY ONE...TONIGHT.

PERIODS OF THUNDERSTORMS ARE EXPECTED ACROSS MUCH OF THE LAKE
THROUGH LATE TONIGHT.

AREAS OF DENSE FOG ARE LIKELY INTO EARLY THIS EVENING.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY.

THERE ARE PERIODIC CHANCES OF THUNDERSTORMS WEDNESDAY THROUGH THE
WEEKEND.

&&

KREIN

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, Jun 15, 4:06 PM CDT, 2 hours 3 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
406 PM CDT MON JUN 15 2015

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

0400 PM     FLOOD            1 N ROCHELLE            41.93N 89.06W
06/15/2015                   OGLE               IL   TRAINED SPOTTER

            WATER OVER CURBS...1-2 FEET DEEP OF STANDING WATER AT RT
            38 AND TURKINGTON TERRACE

&&

BB

Local storm report, Jun 15, 5:17 PM CDT, 52 minutes before

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

Local storm report, Jun 15, 5:43 PM CDT, 26 minutes before

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

Local storm report, Jun 15, 5:47 PM CDT, 22 minutes before

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

Local storm report, Jun 15, 5:48 PM CDT, 21 minutes before

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

Local storm report, Jun 15, 5:52 PM CDT, 17 minutes before

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 14, 7:29 PM CDT	Areal Flood Advisory	LOT	Ford, Livingston	4 hr
Jun 14, 8:40 PM CDT	River Flood Advisory	LOT	Iroquois	3 days
Jun 15, 4:10 AM CDT	Flash Flood Watch	LOT	Boone, DeKalb, DuPage, Ford, Grundy, Iroquois and 10 more	24 hr
Jun 15, 9:23 AM CDT	River Flood Advisory	LOT	Boone	58 hr
Jun 15, 10:13 AM CDT	River Flood Advisory	LOT	Kane, McHenry	45 hr
Jun 15, 10:13 AM CDT	River Flood Advisory	LOT	Kane, Kendall	4 days
Jun 15, 10:13 AM CDT	River Flood Advisory	LOT	LaSalle	62 hr
Jun 15, 10:32 AM CDT	Flash Flood Warning	LOT	Grundy, LaSalle	6 hr
Jun 15, 10:47 AM CDT	Severe Thunderstorm Warning	LOT	DeKalb, Lee	26 min
Jun 15, 11:00 AM CDT	Flash Flood Warning	LOT	Kankakee, Will	6 hr
Jun 15, 11:51 AM CDT	Special Weather Statement	LOT	DuPage	24 min
Jun 15, 2:29 PM CDT	Areal Flood Advisory	LOT	Ford, Iroquois, Kankakee, Livingston	2 hr
Jun 15, 3:08 PM CDT	Flash Flood Warning	LOT	Iroquois, Kankakee	6 hr
Jun 15, 4:24 PM CDT	Flash Flood Warning	LOT	Cook, DeKalb, DuPage, Kane, Lee, Ogle	6 hr
Jun 15, 4:41 PM CDT	Areal Flood Warning	LOT	Grundy, Kankakee, LaSalle, Will	18 hr
Jun 15, 4:50 PM CDT	Tornado Warning	LOT	Cook	25 min
Jun 15, 5:03 PM CDT	Special Marine Warning	LOT		57 min
Jun 15, 5:39 PM CDT	Severe Thunderstorm Warning	LOT	DeKalb, LaSalle	21 min
Jun 15, 6:28 PM CDT	River Flood Advisory	LOT	Cook	25 hr
Jun 15, 6:32 PM CDT	Special Marine Warning	LOT		118 min
Jun 15, 11:19 AM CDT	Special Weather Statement	LOT	Lake	26 min
Jun 15, 11:42 AM CDT	Areal Flood Advisory	LOT	Lake, Porter	2 hr
Jun 15, 2:49 PM CDT	Special Weather Statement	LOT	Jasper	26 min

Nearby

Flash Flood Warnings in Illinois, 2015 Flash Flood Warnings in Indiana, 2015 Every flash flood 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.