Alert archive / Illinois / Red Flag Warnings in 2010

Red Flag Warning 2, NWS St. Louis, MO

April 15, 20104 counties in Illinois

NWS St. Louis, MO issued this red flag warning at Apr 15, 2010, 4:48 AM CDT for 4 counties in Illinois. It took effect at Apr 15, 2010, 12:00 PM CDT. It was in force for 6 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
Apr 15, 2010, 4:48 AM CDT (09:48 UTC)
In effect from
Apr 15, 2010, 12:00 PM CDT
Expired
Apr 15, 2010, 6:00 PM CDT
In force
6 hr
Issued by
NWS St. Louis, MO

Counties Greene County, IL, Jersey County, IL, Macoupin County, IL, Montgomery County, IL

The radar

The St Louis radar (KLSX), 82 km from the middle of the area, began a volume at 09:51 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 00:00Z, 9.8 hours before the alert went out and 160 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 2010-04-15Temperature 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, Lincoln, IL at 00:00Z on 2010-04-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 12 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3446 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
12 m²/s²
0-3 km storm-relative helicity
61 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

671 
WWUS83 KLSX 150948
RFWLSX

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE ST LOUIS MO
448 AM CDT THU APR 15 2010

...HIGH FIRE DANGER THIS AFTERNOON...

.A WARM AND DRY SOUTHWEST WIND WILL PREVAIL OVER THE REGION TODAY.
EXPECT TEMPERATURES TO REMAIN WELL ABOVE NORMAL TODAY. WHILE
RELATIVE HUMIDITY READINGS WILL START OUT RATHER HIGH...IT IS
LIKELY THE HUMIDITY WILL FALL RAPIDLY THIS AFTERNOON DURING THE
PEAK HEATING HOURS. THE LOW RELATIVE HUMIDITY COMBINED WITH DRY
FUELS AND A SUSTAINED WIND OF 15 TO 2O MPH WILL PRODUCE CONDITIONS
WHERE FIRES COULD SPREAD QUICKLY OUT OF CONTROL.

ILZ058>060-099-152300-
/O.NEW.KLSX.FW.W.0002.100415T1700Z-100415T2300Z/
GREENE IL-MACOUPIN IL-MONTGOMERY IL-JERSEY IL-
448 AM CDT THU APR 15 2010

...RED FLAG WARNING IN EFFECT FROM NOON TODAY TO 6 PM CDT THIS
EVENING...

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A RED FLAG
WARNING...WHICH IS IN EFFECT FROM NOON TODAY TO 6 PM CDT THIS
EVENING. 

RELATIVE HUMIDITY VALUES ARE EXPECTED TO DROP BELOW 25 PERCENT
THIS AFTERNOON. THIS LOW HUMIDITY COMBINED WITH DRY FUELS AND A
SUSTAINED WIND OF 15 TO 25 MPH WILL PRODUCE AN ENHANCED FIRE
DANGER THIS AFTERNOON.

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.

&&

$$

CARNEY
1 follow-up statement
456 
WWUS83 KLSX 152254
RFWLSX

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE ST LOUIS MO
554 PM CDT THU APR 15 2010

ILZ058>060-099-160000-
/O.EXP.KLSX.FW.W.0002.000000T0000Z-100415T2300Z/
GREENE IL-MACOUPIN IL-MONTGOMERY IL-JERSEY IL-
554 PM CDT THU APR 15 2010

...RED FLAG WARNING WILL EXPIRE AT 6 PM CDT THIS EVENING...

THE RED FLAG WARNING WILL EXPIRE AT 6 PM CDT THIS EVENING. 

THE COMBINATION OF COOLING TEMPERATURES...RISING RELATIVE HUMIDITY
VALUES...AND DIMINISHING GUSTY WINDS WILL LEAD TO A DECREASE IN
THE FIRE DANGER TONIGHT. THEREFORE...THE RED FLAG WARNING WILL BE
ALLOWED TO EXPIRE.

$$

KANOFSKY

Nearby

Red Flag Warnings in Illinois, 2010Every red flag warning in 2010

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.