Alert archive / Illinois / Red Flag Warnings in 2021

Red Flag Warning 1, NWS Chicago, IL

March 29, 20214 counties in Illinois

NWS Chicago, IL issued this red flag warning at Mar 29, 2021, 4:25 AM CDT for 4 counties in Illinois. It took effect at Mar 29, 2021, 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
Mar 29, 2021, 4:25 AM CDT (09:25 UTC)
In effect from
Mar 29, 2021, 1:00 PM CDT
Expired
Mar 29, 2021, 8:00 PM CDT
In force
7 hr
Issued by
NWS Chicago, IL

Counties Boone County, IL, Lee County, IL, Ogle County, IL, Winnebago County, IL

The radar

The Chicago radar (KLOT), 105 km from the middle of the area, began a volume at 09:29 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, 9.4 hours before the alert went out and 124 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 2021-03-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2021-03-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 53 square meters per square second.1939587897Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1587 m above ground
0-6 km bulk shear
48 kt
0-1 km storm-relative helicity
53 m²/s²
0-3 km storm-relative helicity
119 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

369 
WWUS83 KLOT 290925
RFWLOT

URGENT - FIRE WEATHER MESSAGE
National Weather Service Chicago IL
425 AM CDT Mon Mar 29 2021

...HIGH FIRE DANGER TODAY...

ILZ003-004-008-010-291730-
/O.NEW.KLOT.FW.W.0001.210329T1800Z-210330T0100Z/
Winnebago-Boone-Ogle-Lee-
425 AM CDT Mon Mar 29 2021

...RED FLAG WARNING IN EFFECT FROM 1 PM THIS AFTERNOON TO 8 PM
CDT THIS EVENING FOR NORTH-CENTRAL ILLINOIS...

The National Weather Service in Chicago has issued a Red Flag
Warning, which is in effect from 1 PM this afternoon to 8 PM CDT 
this evening.

* Affected Area...Winnebago, Boone, Ogle and Lee.

* Winds...South around 20 to 30 mph with gusts up to 45 mph.

* Timing...This afternoon and early evening

* Relative Humidity...As low as 25 percent.

* Impacts...The combination of strong winds, very low relative
  humidity, mild temperatures, and exceptionally dry fuels will
  likely promote extremely dangerous behavior of any fires. Any
  fires that develop outdoors will likely spread rapidly. Any
  planned outdoor burning should be postponed today.

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 can
contribute to extreme fire behavior.

&&

$$

Ogorek
3 follow-up statements
375 
WWUS83 KLOT 291552
RFWLOT

URGENT - FIRE WEATHER MESSAGE
National Weather Service Chicago IL
1052 AM CDT Mon Mar 29 2021

...HIGH FIRE DANGER TODAY...

ILZ003-004-008-010-300000-
/O.CON.KLOT.FW.W.0001.210329T1800Z-210330T0100Z/
Winnebago-Boone-Ogle-Lee-
1052 AM CDT Mon Mar 29 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM CDT THIS EVENING
FOR NORTH-CENTRAL ILLINOIS...

* Affected Area...Winnebago, Boone, Ogle and Lee counties.

* Winds...South around 20 to 30 mph with gusts up to 45 mph.

* Timing...This afternoon and early evening

* Relative Humidity...As low as 25 percent.

* Impacts...The combination of strong winds, very low relative 
  humidity, mild temperatures, and exceptionally dry fuels will 
  likely promote extremely dangerous behavior of any fires. Any 
  fires that develop outdoors will likely spread rapidly. Any 
  planned outdoor burning should be postponed today.

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 can
contribute to extreme fire behavior.

&&

$$
401 
WWUS83 KLOT 292028
RFWLOT

URGENT - FIRE WEATHER MESSAGE
National Weather Service Chicago IL
328 PM CDT Mon Mar 29 2021

...HIGH FIRE DANGER CONTINUES INTO EARLY EVENING...

ILZ003-004-008-010-300100-
/O.CON.KLOT.FW.W.0001.000000T0000Z-210330T0100Z/
Winnebago-Boone-Ogle-Lee-
328 PM CDT Mon Mar 29 2021

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 8 PM CDT THIS EVENING
FOR NORTH-CENTRAL ILLINOIS...

* Affected Area...Winnebago, Boone, Ogle and Lee.

* Winds...South around 25 mph with gusts up to 45 mph.

* Timing...Through early evening.

* Relative Humidity...As low as 25 to 30 percent.

* Impacts...The combination of strong winds, very low relative
  humidity, mild temperatures, and exceptionally dry fuels will
  likely promote extremely dangerous behavior of any fires. Any
  fires that develop outdoors will likely spread rapidly. Any
  planned outdoor burning should be postponed today and tonight.

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 can
contribute to extreme fire behavior.

&&

$$
206 
WWUS83 KLOT 300105
RFWLOT

URGENT - FIRE WEATHER MESSAGE
National Weather Service Chicago IL
805 PM CDT Mon Mar 29 2021

ILZ003-004-008-010-300215-
/O.EXP.KLOT.FW.W.0001.000000T0000Z-210330T0100Z/
Winnebago-Boone-Ogle-Lee-
805 PM CDT Mon Mar 29 2021

...RED FLAG WARNING HAS EXPIRED FOR NORTH CENTRAL ILLINOIS...

Relative humidity levels will slowly rise tonight with the fire
danger threat decreasing. It will remain windy into the overnight
hours.

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Mar 28, 10:07 PM CDTGale WarningLOT29 hr
Mar 29, 2:56 AM CDTWind AdvisoryLOTBoone, Cook, DuPage, Lake, Lee, Ogle and 2 more22 hr
Mar 29, 3:06 AM CDTSmall Craft AdvisoryLOT15 hr
Mar 29, 2:52 PM CDTSmall Craft AdvisoryLOT43 hr

Nearby

Red Flag Warnings in Illinois, 2021Every red flag warning in 2021

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.