Alert archive / Illinois / Flash Flood Warnings in 2013

Flash Flood Warning 22, NWS Chicago, IL

June 26, 2013Cook County, DuPage County, Kane County, Illinois

NWS Chicago, IL issued this flash flood warning at Jun 26, 2013, 7:13 AM CDT for Cook County, DuPage County, Kane County, Illinois. 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 26, 2013, 7:13 AM CDT (12:13 UTC)
Expired
Jun 26, 2013, 11:30 AM CDT
In force
4 hr
Issued by
NWS Chicago, IL
Area
Storm-based polygon
Flood severity
None

Counties Cook County, IL, DuPage County, IL, Kane County, IL

The radar

The Chicago radar (KLOT), 32 km from the middle of the area, began a volume at 12:13 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, 0.2 hours before the alert went out and 199 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 12:00Z on 2013-06-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1818 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 12:00Z on 2013-06-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 44 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
1818 J/kg
Mixed-layer CIN
-63 J/kg
Mixed-layer LCL
874 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
44 m²/s²
0-3 km storm-relative helicity
82 m²/s²
Significant tornado parameter
0.1
Supercell composite
0.5

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 26, 6:29 AM CDT, 44 minutes earlier.

Area forecast discussion, Jun 26, 6:29 AM CDT, 44 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
629 AM CDT WED JUN 26 2013

.DISCUSSION...
308 AM CDT

THE LATEST IN A SERIES OF WEAK SHORTWAVES IN QUASI-ZONAL SOUTHERN
STREAM FLOW HAS BEEN SUPPORTING WIDESPREAD CONVECTION AS IT MOVES
TOWARD THE AREA EARLY THIS MORNING.  GRADUALLY OVER THE NEXT TWO
DAYS THE LARGE SCALE PATTERN WILL BE AMPLIFYING INTO A BROAD
ANTICYCLONE ACROSS THE WESTERN CONUS AND A DEEPENING LONGWAVE TROUGH
OVER THE EASTERN STATES.  THE WARM HUMID CONDITIONS OF RECENT DAYS
WILL BE REPLACED BY COOL HUMID CONDITIONS BY THE WEEKEND...WHICH
THEN WILL PERSIST INTO NEXT WEEK.

FIRST QUESTION CONCERNS PRECIPITATION TRENDS FOR TODAY.  AT 08Z THE
EXISTING AREAS OF CONVECTION ACROSS NORTHEAST IOWA INTO NORTHERN
ILLINOIS WERE LOCATED ALONG FAVORABLE GRADIENTS OF MOISTURE
TRANSPORT ON THE LEADING EDGE OF THE LOW LEVEL JET...AND UNDER A
WEAK SHORTWAVE DEPICTED IN THE RAP MODEL AND VWP OBS AT 850 AND 700
MB.  THIS ACTIVITY SHOULD BE MOVING ACROSS NORTHEASTERN ILLINOIS
DURING THE PREDAWN HOURS BUT THEN BEGINNING TO WEAKEN AS THE
LLJ VEERS AND ADJUSTS ITS FOCUS MORE TOWARD CENTRAL AND SOUTHERN
ILLINOIS.

IF THIS ACTIVITY DOES DISSIPATE AS EXPECTED TOWARD MORNING...THE
PROSPECTS OF REDEVELOPMENT TODAY ARE SOMEWHAT UNCERTAIN DESPITE
MODEL QPF SOLUTIONS TO THE CONTRARY.  LINGERING MORNING SHOWERS AND
THEN SCATTERED TSRA LATER ARE DEFINITELY NOT OUT OF THE QUESTION
LOCALLY BUT THE MORE FAVORABLE AREAS OF MOISTURE ADVECTION AND STEEP
MID LEVEL LAPSE RATES ARE FARTHER SOUTH TOWARD CENTRAL ILLINOIS AND
FARTHER NORTH ALONG THE WI/MN STATE LINE.

DESPITE THE APPROACH OF A SURFACE/850 FRONTAL ZONE...THE UPPER LEVEL
WAVES APPEAR TO BE SOMEWHAT OUT OF SYNC AND MORE
PROGRESSIVE...LEAVING THE LOWER LEVEL FEATURES UNDER AREAS OF RISING
HEIGHTS ALOFT.  IN THE 0530Z SPC DAY 1 OUTLOOK THE SLIGHT RISK
EXTENDS NORTHWEST TOWARD MSP AND THEN WELL SOUTH AND EAST THROUGH
THE TENNESSEE AND OHIO VALLEYS.  WOULD NOT BE SURPRISED TO SEE THIS
SPLIT IN LATER UPDATES...WITH THE THUMB TO OUR NORTHWEST SEPARATED
FROM THE AREA TO OUR SOUTH.  BUT THAT WOULD BE CUTTING IT PRETTY
FINE GIVEN THE OVERALL UNCERTAINTY WITH THIS SITUATION.

LONG STORY SHORT...FOR TODAY THE PLAN WILL BE TO LOWER POPS INTO THE
CHANCE CATEGORY BY AFTERNOON FOR MOST OF THE AREA BUT KEEP IN MIND
THE PWATS APPROACHING TWO INCHES AND THEREFORE MAINTAIN THE FLASH
FLOOD WATCH AND THE MENTION OF TSRA.

AFTER TODAY THE SITUATION BECOMES ONLY SLIGHTLY MORE CLEAR BUT OF
SEEMINGLY LESSER IMPACT.

AMPLIFICATION OF THE LARGE SCALE FLOW WILL BEGIN TO INFLUENCE THE
LOCAL AREA BY TONIGHT INTO THURSDAY AFTER THE SURFACE TROUGH PUSHES
THROUGH THE AREA AND WINDS AT ALL LEVELS TURN TO THE NORTHWEST.  LOW
LEVEL WARMTH AND HUMIDITY DO NOT REALLY DEPART UNTIL FRIDAY WHEN THE
EXPANDING EASTERN TROUGH PUSHES THE UPPER JET SOUTH OF THE AREA AND
USHERS IN SLIGHTLY DRIER BUT MILDER AIR.

WITH ONLY MARGINAL LAPSE RATES AND HEIGHTS ALOFT CONTINUING TO
INCREASE...NEITHER THURSDAY NOR FRIDAY LOOK PARTICULARLY FAVORABLE
FOR WIDESPREAD PRECIPITATION.  AS MENTIONED IN AN EARLIER
DISCUSSION...IT WOULD NOT TAKE MUCH OF A SHORTWAVE IN THE UPPER FLOW
TO SUPPORT AN AFTERNOON SHOWER...SO WILL CONTINUE TO CARRY SLIGHT
CHANCE POPS ON BOTH DAYS.

BY THE WEEKEND THE CONVECTIVE INSTABILITY APPEARS TO HAVE
DECREASED...BUT THE PRESENCE OF BOTH A SURFACE AND UPPER LEVEL
TROUGH DROPPING SOUTH ACROSS THE AREA WILL STILL SUPPORT LARGE SCALE
LIFT...PRIMARILY TO THE SOUTH ON SUNDAY.  PRECIP CHANCES FINALLY
DECREASE BY EARLY NEXT WEEK AS THE SURFACE AND UPPER SUPPORT
DIMINISH...BUT UNSEASONABLY COOL AIR REMAINS IN PLACE WITH CONTINUED
NORTH TO NORTHEASTERLY WINDS.

LENNING

&&

.AVIATION...

//ORD AND MDW CONCERNS...UPDATED 12Z...

* LINE OT THUNDERSTORMS EARLY THIS MORNING BACK BUILDING
  SOUTH...BUT SHOULD EVENTUALLY BEGIN TO LIFT NORTH AWAY FROM AREA
  AND WEAKEN.
* ADDITIONAL THUNDERSTORMS POSSIBLE THIS AFTERNOON ASSOCIATED WITH
  THE DECAYING SYSTEM MOVING ACROSS THE MISSISSIPPI.

BMD

//DISCUSSION...UPDATED 12Z...

LINE OF THUNDERSTORMS SPANS FROM NORTH CENTRAL ILLINOIS ESE INTO
NORTHERN INDIANA AND IS FOCUSED ON THE NOSE OF A LOW LEVEL JET.
WHILE THE FOCUS SHOULD GENERALLY LIFT NORTH AND WEAKEN OVER THE NEXT
COUPLE HOURS...THE STORMS HAVE BEEN BACK BUILDING TO THE SOUTH WHICH
HAS KEPT IT OVER OR ON THE DOORSTEP ON ORD...AND MAY CONTINUE TO
PERSIST OVER THE NEXT HOUR OR TWO. WINDS HAVE BECOME MORE
NORTHEAST/EASTERLY UNDER THE INFLUENCE OF CONVECTION...AND CIGS HAVE
DROPPED TO MVFR. AS CONVECTION WANES THIS MORNING...EXPECT SOUTHERLY
WINDS TO RESUME AND FOR MVFR CIGS TO LIFT BACK TO VFR. THERE SHOULD
BE A LULL IN ACTIVITY FROM MID MORNING TO EARLY THIS AFTERNOON FOR
THE CHICAGO TERMINALS. ATTENTION TURNS TO AN APPROACHING MCV MOVING
OVER THE MISSISSIPPI RIVER EARLY THIS MORNING. WHILE THERE IS AN
EXPANSIVE AREA OF STRATIFORM PRECIP AHEAD OF THIS FEATURE...IT
SHOULD DRY/ERODE SOME AS IT PROGRESSES EAST. BECAUSE OF THE CLOUD
COVER AND PERHAPS LIGHT RAIN...IT APPEARS THERE WILL BE LITTLE
OPPORTUNITY FOR THE ATMOSPHERE TO DESTABILIZE TODAY THOUGH THERE
WILL BE SOME PERSISTENT/FESTERING EMBEDDED CONVECTION ASSOCIATED
WITH THE MCV. WINDS APPEAR TO GO LIGHT AND VARIABLE TONIGHT...AND
NAM GUIDANCE AS WELL AS LAV POINT TO FOG/BR AND IFR CIGS DEVELOPING
OVERNIGHT. WILL NOT MENTION YET IN TAFS TO WAIT AND SEE HOW THE REST
OF THE DAY EVOLVES AND IF THERE IS ANY SIGNIFICANT DRYING THIS
AFTERNOON/EVENING.

BMD

//ORD AND MDW CONFIDENCE...UPDATED 12Z...

* MEDIUM CONFIDENCE IN A LULL IN PRECIP/TSRA MID MORNING TO EARLY
  AFTERNOON.
* LOW CONFIDENCE IN EVOLUTION OF MCV AND RESULTING PRECIP/TSRA
  CHANCES THIS AFTERNOON.
* LOW TO MEDIUM CONFIDENCE IN WIND TRENDS.

BMD

//OUTLOOK FOR ORD/MDW FOR 00Z FRIDAY-12Z WEDNESDAY...UPDATED 12Z...

THURSDAY NIGHT...VFR.
FRIDAY THROUGH SATURDAY...PERIODIC CHANCES OF TSRA.
SATURDAY THROUGH MONDAY...PERIODIC CHANCES OF SHRA.
TUESDAY...CHC TSRA.

BMD

&&

.MARINE...
150 AM CDT

ELONGATED SFC LOW PRESSURE TROUGH OVER THE MID-UPPER MISSOURI
VALLEY WILL MOVE SLOWLY EAST TODAY...WITH VARYING MODEL FORECASTS
DEVELOPING A WEAK SURFACE LOW PRESSURE WAVE IN THE VICINITY OF
NORTHERN IL/IND OR SOUTHERN LAKE MICHIGAN BY THIS EVENING. SOUTH
TO SOUTHEAST WINDS SHOULD DIMINISH IN SPEED AS THE GRADIENT
WEAKENS WITH THE APPROACH OF THE TROUGH THIS AFTERNOON...WITH LAKE
BREEZE ESPECIALLY ALONG THE WESTERN SHORE. THUNDERSTORMS WILL BE
POSSIBLE ESPECIALLY OVER THE SOUTHERN HALF OF THE LAKE...WHICH MAY
RESULT IN SOME LOCALLY STRONGER WINDS. WINDS MAY BECOME SOMEWHAT
VARIABLE AT 10 KT OR LESS TONIGHT AS THE SURFACE TROUGH/COLD FRONT
MOVE SLOWLY ACROSS THE LAKE...EVENTUALLY TAKING ON A WEST-
NORTHWEST DIRECTION THURSDAY AS THE TROUGH MOVES OFF TO THE EAST.
SPEEDS SHOULD REMAIN GENERALLY LIGHT HOWEVER...WITH A RELATIVELY
WEAK GRADIENT INTO FRIDAY.

WEAK HIGH PRESSURE RIDGING WILL DEVELOP SOUTHEAST ACROSS THE
NORTHERN AND CENTRAL HIGH PLAINS INTO THE WEEKEND...WHILE THE LOW
PRESSURE WAVE EVENTUALLY DEEPENS EAST OF THE LAKES. THIS WILL
MAINTAIN A PROLONGED PERIOD OF NORTH-NORTHWEST FLOW ACROSS LAKE
MICHIGAN...THOUGH AGAIN WITH SPEEDS GENERALLY 15 KT OR LESS THROUGH
THE PERIOD.

OTHERWISE...IN THE NEAR TERM SOME PATCHY DENSE FOG WILL LINGER
ACROSS THE NORTHERN PART OF THE LAKE THIS MORNING.

RATZER

&&

.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FLASH FLOOD WATCH...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
     ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
     ILZ023-ILZ032-ILZ033-ILZ039 UNTIL 7 PM WEDNESDAY.

IN...FLASH FLOOD WATCH...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL 7
     PM WEDNESDAY.

LM...NONE.
&&

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

FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Hazardous weather outlook, Jun 26, 5:19 AM CDT, 1 hour 54 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
519 AM CDT WED JUN 26 2013

ILZ003>006-008-010>014-019>023-032-033-039-INZ001-002-010-011-019-
271030-
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-
519 AM CDT WED JUN 26 2013 /619 AM EDT WED JUN 26 2013/

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

.DAY ONE...TODAY AND TONIGHT.

  WEATHER HAZARDS EXPECTED:

   THUNDERSTORMS...THE STRONGEST MAY PRODUCE:
    HEAVY RAIN AND FLASH FLOODING
    FREQUENT CLOUD TO GROUND LIGHTNING.
    HAIL TO THE SIZE OF QUARTERS.
    WINDS TO 60 MPH.

  AREAS AFFECTED AND TIMING:

   EARLY THIS MORNING THE HEAVIEST RAINFALL WILL BE ACROSS FAR
   NORTHERN ILLINOIS...BUT THE FOCUS WILL GRADUALLY SHIFT SOUTH
   AS THE DAY PROGRESSES. NEW DEVELOPMENT THIS AFTERNOON AND
   EVENING ALSO WOULD HAVE THE POTENTIAL TO PRODUCE HEAVY RAIN
   ALONG WITH LARGE HAIL AND STRONG WINDS...BUT THE TIMING AND
   EXTENT OF THIS ACTIVITY IS LESS CERTAIN AT THIS TIME.

  DISCUSSION:

   CONVECTIVE ACTIVITY OVER AND UPSTREAM OF THE AREA EARLY THIS
   MORNING IS EXPECTED TO DECREASE IN COVERAGE AND INTENSITY
   FAIRLY SOON AFTER SUNRISE...THOUGH A FEW SHOWERS COULD LINGER
   INTO MID MORNING. ANY OF THE STORMS THIS MORNING...OR NEW
   STORMS THAT MAY DEVELOP THIS AFTERNOON OR EVENING...WOULD HAVE
   THE POTENTIAL TO GENERATE HEAVY RAINFALL RATES THAT COULD
   RESULT IN FLASH FLOODING. HAIL AND STRONG WINDS ALSO ARE A
   POSSIBILITY...BUT MORE LIKELY TOWARD LATE AFTERNOON OR EVENING
   IF NEW STORMS DO MANAGE TO DEVELOP.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY.

THERE WILL PERIODIC BUT LESSER CHANCES FOR THUNDERSTORMS THURSDAY
AND FRIDAY.

RUNOFF FROM THUNDERSTORMS AND HEAVY RAIN THIS WEEK COULD PRODUCE
SIGNIFICANT RISES ON AREA RIVERS OVER THE NEXT THREE DAYS. THE
FOX...ROCK...DES PLAINES...ILLINOIS...AND PECATONICA ARE FORECAST
TO APPROACH OR EXCEED FLOOD OR ACTION STAGE.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS MAY BE NEEDED THROUGH THE DAY TO REPORT HEAVY RAINFALL OR
ANY SEVERE WEATHER THAT MAY OCCUR.

&&

LMZ740>745-271030-
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-
519 AM CDT WED JUN 26 2013

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

.DAY ONE...TODAY AND TONIGHT.

THUNDERSTORMS ARE LIKELY EARLY THIS MORNING...AND THERE IS A
CONTINUED CHANCE OF THUNDERSTORMS LATER TODAY AND TONIGHT. SOME
STORMS MAY PRODUCE SMALL HAIL AND GUSTY WINDS IN EXCESS OF 30
KT.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY.

THERE WILL BE PERIODIC CHANCES FOR THUNDERSTORMS THURSDAY
THROUGH FRIDAY...WITH LESSER CHANCES THIS WEEKEND INTO EARLY NEXT
WEEK.

&&

LMZ080-261-362-364-366-563-565-567-669-671-673-675-777-779-868-
870-872-874-876-878-271030-
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-
519 AM CDT WED JUN 26 2013

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

.DAY ONE...TODAY AND TONIGHT.

THUNDERSTORMS ARE LIKELY EARLY THIS MORNING ACROSS THE SOUTHERN
PORTION OF THE LAKE...AND THERE IS A CONTINUED CHANCE OF
THUNDERSTORMS THIS AFTERNOON AND EVENING. SOME COULD PRODUCE
STRONG WINDS AND SMALL HAIL.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY.

THERE WILL BE PERIODIC CHANCES FOR THUNDERSTORMS THURSDAY AND
FRIDAY...WITH LESSER CHANCES THIS WEEKEND INTO EARLY NEXT WEEK.

&&

LENNING

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

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

In the hours before

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Local storm report, Jun 26, 7:00 AM CDT, 13 minutes before
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Local storm report, Jun 26, 7:07 AM CDT, 6 minutes before
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Local storm report, Jun 26, 7:10 AM CDT, 3 minutes before
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The office that day

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

IssuedProductOfficeCountiesLasted
Jun 25, 11:28 PM CDTRiver Flood WatchLOTBureau, LaSalle12 hr
Jun 25, 11:28 PM CDTSpecial Weather StatementLOTIroquois47 min
Jun 25, 11:33 PM CDTRiver Flood AdvisoryLOTLee11 hr
Jun 25, 11:33 PM CDTRiver Flood AdvisoryLOTKane, Kendall12 hr
Jun 26, 12:11 AM CDTSpecial Weather StatementLOTIroquois34 min
Jun 26, 2:53 AM CDTSpecial Weather StatementLOTBoone37 min
Jun 26, 3:52 AM CDTAreal Flood AdvisoryLOTBoone, McHenry6 hr
Jun 26, 4:33 AM CDTAreal Flood AdvisoryLOTCook, Lake, McHenry6 hr
Jun 26, 5:26 AM CDTFlash Flood WarningLOTBoone, Cook, Lake, McHenry6 hr
Jun 26, 5:43 AM CDTRiver Flood WarningLOTWinnebago10 days
Jun 26, 8:34 AM CDTSevere Thunderstorm WarningLOTFord, Grundy, Kankakee, Kendall, LaSalle, Livingston and 1 more26 min
Jun 26, 8:37 AM CDTRiver Flood WarningLOTCook56 hr
Jun 26, 8:37 AM CDTRiver Flood WarningLOTKane, McHenry9 days
Jun 26, 9:03 AM CDTSpecial Weather StatementLOTFord, Iroquois, Kankakee, Will57 min
Jun 26, 9:25 AM CDTSpecial Weather StatementLOTBoone, DeKalb, McHenry, Winnebago65 min
Jun 26, 9:43 AM CDTAreal Flood AdvisoryLOTBoone, Winnebago3 hr
Jun 26, 9:52 AM CDTSpecial Weather StatementLOTCook38 min
Jun 26, 10:14 AM CDTRiver Flood WarningLOTWinnebago9 days
Jun 26, 10:23 AM CDTFlash Flood WarningLOTBoone, Winnebago6 hr
Jun 26, 10:37 AM CDTRiver Flood WatchLOTLee5 hr
Jun 26, 10:38 AM CDTFlash Flood WarningLOTBoone, Cook, DuPage, Kane, Lake, McHenry6 hr
Jun 26, 10:56 AM CDTRiver Flood AdvisoryLOTBoone5 hr
Jun 26, 10:56 AM CDTRiver Flood AdvisoryLOTWinnebago5 hr
Jun 26, 11:06 AM CDTRiver Flood WarningLOTKane, Kendall6 days
Jun 26, 11:19 AM CDTRiver Flood WatchLOTCook22 hr
Jun 26, 11:22 AM CDTRiver Flood AdvisoryLOTLake70 hr
Jun 26, 11:34 AM CDTRiver Flood AdvisoryLOTCook23 hr
Jun 26, 11:44 AM CDTRiver Flood AdvisoryLOTBureau, LaSalle23 hr
Jun 26, 1:37 PM CDTRiver Flood AdvisoryLOTLake16 hr
Jun 26, 3:46 PM CDTRiver Flood WarningLOTOgle5 days
Jun 26, 3:46 PM CDTRiver Flood WarningLOTLee28 hr
Jun 26, 3:46 PM CDTRiver Flood WarningLOTBoone42 hr
Jun 26, 3:46 PM CDTRiver Flood WarningLOTWinnebago60 hr
Jun 26, 3:46 PM CDTRiver Flood WarningLOTWinnebago28 hr
Jun 26, 4:27 PM CDTFlash Flood WarningLOTBoone, Cook, Kane, Lake, McHenry18 hr
Jun 25, 7:46 PM CDTSevere Thunderstorm WarningLOTPorter29 min
Jun 26, 7:25 AM CDTFlash Flood WarningLOTLake, Porter6 hr
Jun 26, 4:11 PM CDTSpecial Weather StatementLOTJasper34 min

Nearby

Flash Flood Warnings in Illinois, 2013Every flash flood warning in 2013

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.