Alert archive / Illinois / Red Flag Warnings in 2012

Red Flag Warning 9, NWS Chicago, IL

May 29, 2012Lake County, Indiana; 8 counties in Illinois

NWS Chicago, IL issued this red flag warning at May 29, 2012, 3:13 AM CDT for Lake County, Indiana; 8 counties in Illinois. It took effect at May 29, 2012, 1:00 PM CDT. It was in force for 7 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
May 29, 2012, 3:13 AM CDT (08:13 UTC)
In effect from
May 29, 2012, 1:00 PM CDT
Expired
May 29, 2012, 8:00 PM CDT
In force
7 hr
Issued by
NWS Chicago, IL

Counties Cook County, IL, DeKalb County, IL, DuPage County, IL, Kane County, IL, Kendall County, IL, Lee County, IL, Ogle County, IL, Will County, IL, Lake County, IN

The radar

The Chicago radar (KLOT), 30 km from the middle of the area, began a volume at 08:15 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

Davenport, (KDVN), launched 00:00Z, 8.2 hours before the alert went out and 178 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 2012-05-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 795 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Davenport, at 00:00Z on 2012-05-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -47 square meters per square second.19395878Sfc1 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
795 J/kg
Mixed-layer CIN
-98 J/kg
Mixed-layer LCL
1457 m above ground
0-6 km bulk shear
54 kt
0-1 km storm-relative helicity
-47 m²/s²
0-3 km storm-relative helicity
21 m²/s²
Significant tornado parameter
-0.1
Supercell composite
-1.5

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

411 
WWUS83 KLOT 290813
RFWLOT

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE CHICAGO IL
313 AM CDT TUE MAY 29 2012

ILZ008-010>014-020-022-INZ001-291615-
/O.NEW.KLOT.FW.W.0009.120529T1800Z-120530T0100Z/
OGLE-LEE-DE KALB-KANE-DUPAGE-COOK-KENDALL-WILL-LAKE IN-
313 AM CDT TUE MAY 29 2012

...RED FLAG WARNING IN EFFECT FROM 1 PM THIS AFTERNOON TO 8 PM
CDT THIS EVENING...

THE NATIONAL WEATHER SERVICE IN CHICAGO HAS ISSUED A RED FLAG
WARNING FOR STRONG WINDS...LOW RELATIVE HUMIDITY...AND 
ABNORMALLY DRY CONDITIONS...WHICH IS IN EFFECT FROM 1 PM THIS
AFTERNOON TO 8 PM CDT THIS EVENING.

* AFFECTED AREA...PORTIONS OF NORTHERN ILLINOIS AS WELL AS LAKE
  COUNTY INDIANA.

* 20FT WINDS...WEST 15 TO 20 MPH WITH GUSTS UP TO 30 MPH.

* TIMING...THE STRONGEST WINDS AND LOWEST RELATIVE HUMIDITY
  VALUES ARE EXPECTED THIS AFTERNOON.

* RELATIVE HUMIDITY...AS LOW AS 20 TO 25 PERCENT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A RED FLAG WARNING MEANS THAT CRITICAL FIRE WEATHER CONDITIONS
ARE EITHER OCCURRING NOW...OR WILL SHORTLY. A COMBINATION OF
STRONG WINDS...LOW RELATIVE HUMIDITY...AND WARM TEMPERATURES WILL
CREATE EXPLOSIVE FIRE GROWTH POTENTIAL.

&&

$$

IZZI
3 follow-up statements
754 
WWUS83 KLOT 291522
RFWLOT

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE CHICAGO IL
1022 AM CDT TUE MAY 29 2012

ILZ008-010>014-020-022-INZ001-292330-
/O.CON.KLOT.FW.W.0009.120529T1800Z-120530T0100Z/
OGLE-LEE-DE KALB-KANE-DUPAGE-COOK-KENDALL-WILL-LAKE IN-
1022 AM CDT TUE MAY 29 2012

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM CDT THIS
EVENING...

* AFFECTED AREA...PORTIONS OF NORTHERN ILLINOIS AS WELL AS LAKE
  COUNTY INDIANA.

* 20FT WINDS...WEST 15 TO 20 MPH WITH GUSTS UP TO 30 MPH.

* TIMING...THE STRONGEST WINDS AND LOWEST RELATIVE HUMIDITY 
  VALUES ARE EXPECTED THIS AFTERNOON. 

* RELATIVE HUMIDITY...AS LOW AS 20 TO 25 PERCENT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A RED FLAG WARNING MEANS THAT CRITICAL FIRE WEATHER CONDITIONS
ARE EITHER OCCURRING NOW...OR WILL SHORTLY. A COMBINATION OF
STRONG WINDS...LOW RELATIVE HUMIDITY...AND WARM TEMPERATURES WILL
CREATE EXPLOSIVE FIRE GROWTH POTENTIAL.

&&

$$
723 
WWUS83 KLOT 292054
RFWLOT

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE CHICAGO IL
354 PM CDT TUE MAY 29 2012

ILZ008-010>014-020-022-INZ001-300100-
/O.CON.KLOT.FW.W.0009.000000T0000Z-120530T0100Z/
OGLE-LEE-DE KALB-KANE-DUPAGE-COOK-KENDALL-WILL-LAKE IN-
354 PM CDT TUE MAY 29 2012

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM CDT THIS
EVENING...

* AFFECTED AREA...PORTIONS OF NORTHERN ILLINOIS AS WELL AS LAKE
  COUNTY INDIANA.

* 20FT WINDS...WEST 15 TO 20 MPH WITH GUSTS UP TO 30 MPH.

* TIMING...THE STRONGEST WINDS AND LOWEST RELATIVE HUMIDITY 
  VALUES ARE EXPECTED THIS AFTERNOON. 

* RELATIVE HUMIDITY...AS LOW AS 20 TO 25 PERCENT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A RED FLAG WARNING MEANS THAT CRITICAL FIRE WEATHER CONDITIONS
ARE EITHER OCCURRING NOW...OR WILL SHORTLY. A COMBINATION OF
STRONG WINDS...LOW RELATIVE HUMIDITY...AND WARM TEMPERATURES WILL
CREATE EXPLOSIVE FIRE GROWTH POTENTIAL.

&&

$$

BEACHLER
325 
WWUS83 KLOT 300045
RFWLOT

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE CHICAGO IL
745 PM CDT TUE MAY 29 2012

...DANGEROUS FIRE WEATHER CONDITIONS EASING...

ILZ008-010>014-020-022-INZ001-300145-
/O.EXP.KLOT.FW.W.0009.000000T0000Z-120530T0100Z/
OGLE-LEE-DE KALB-KANE-DUPAGE-COOK-KENDALL-WILL-LAKE IN-
745 PM CDT TUE MAY 29 2012

...RED FLAG WARNING WILL EXPIRE AT 8 PM CDT THIS EVENING...

WIND SPEEDS HAVE DIMINISHED EARLY THIS EVENING AND HUMIDITY IS
GRADUALLY INCREASING...ALLOWING FOR LESS OF A FIRE DANGER
CONCERN. THUS...THE RED FLAG WARNING IN EFFECT FOR PART OF
NORTHERN ILLINOIS WILL BE ALLOWED TO EXPIRE.

$$

The office that day

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

IssuedProductOfficeCountiesLasted
May 28, 7:14 PM CDTSpecial Weather StatementLOTLee31 min
May 28, 7:22 PM CDTSpecial Weather StatementLOTCook23 min
May 28, 7:58 PM CDTSpecial Weather StatementLOTLaSalle47 min
May 28, 9:49 PM CDTSpecial Weather StatementLOTLaSalle41 min
May 29, 3:18 AM CDTSmall Craft AdvisoryLOT18 hr

Nearby

Red Flag Warnings in Illinois, 2012Red Flag Warnings in Indiana, 2012Every red flag warning in 2012

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.