Alert archive / Illinois / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 32, NWS St. Louis, MO

April 9, 2011Calhoun County, Jersey County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Apr 9, 2011, 4:19 AM CDT for Calhoun County, Jersey County, Illinois. It was in force for 26 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Apr 9, 2011, 4:19 AM CDT (09:19 UTC)
Expired: Apr 9, 2011, 4:45 AM CDT
In force: 26 min
Issued by: NWS St. Louis, MO
Area: Storm-based polygon
Hail: 1.0 in
Wind: 50.0 mph

Counties Calhoun County, IL, Jersey County, IL

The radar

The St Louis radar (KLSX), 39 km from the middle of the area, began a volume at 09:21 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, 9.3 hours before the alert went out and 208 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 637 m above ground
0-6 km bulk shear: 47 kt
0-1 km storm-relative helicity: 158 m²/s²
0-3 km storm-relative helicity: 242 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.

056 
WUUS53 KLSX 090919
SVRLSX
ILC013-083-090945-
/O.NEW.KLSX.SV.W.0032.110409T0919Z-110409T0945Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
419 AM CDT SAT APR 9 2011

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CALHOUN COUNTY IN SOUTHWEST ILLINOIS...
  SOUTHWESTERN JERSEY COUNTY IN SOUTHWEST ILLINOIS...

* UNTIL 445 AM CDT

* AT 416 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL.  THIS
  STORM WAS LOCATED 6 MILES EAST OF WINFIELD...OR 11 MILES NORTHEAST
  OF ST. PAUL...AND MOVING EAST AT 35 MPH.

* LOCATIONS IMPACTED INCLUDE...
  GRAFTON...DEER PLAIN...NUTWOOD AND FIELDON.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 60 MILES PER
HOUR...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN. FOR
YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR
HOME OR BUSINESS. HEAVY RAINS FLOOD ROADS QUICKLY SO DO NOT DRIVE
INTO AREAS WHERE WATER COVERS THE ROAD.

&&

LAT...LON 3917 9050 3898 9037 3896 9043 3896 9047
      3894 9049 3891 9057 3890 9065 3904 9071
      3910 9069 3913 9061 3912 9061 3913 9059
TIME...MOT...LOC 0919Z 252DEG 33KT 3900 9060
WIND...HAIL <50MPH 1.00IN

$$

TILLY

1 follow-up statement

162 
WWUS53 KLSX 090941
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
441 AM CDT SAT APR 9 2011

ILC013-083-090951-
/O.EXP.KLSX.SV.W.0032.000000T0000Z-110409T0945Z/
JERSEY IL-CALHOUN IL-
441 AM CDT SAT APR 9 2011

...THE SEVERE THUNDERSTORM WARNING FOR CALHOUN AND SOUTHWESTERN
JERSEY COUNTIES WILL EXPIRE AT 445 AM CDT...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED BELOW SEVERE
LIMITS...AND NO LONGER POSES AN IMMEDIATE THREAT TO LIFE OR PROPERTY.
 HOWEVER HEAVY RAIN IS STILL POSSIBLE WITH THIS THUNDERSTORM.

LAT...LON 3917 9050 3898 9037 3896 9043 3896 9047
      3894 9049 3891 9057 3890 9065 3904 9071
      3910 9069 3913 9061 3912 9061 3913 9059
TIME...MOT...LOC 0941Z 249DEG 24KT 3906 9041

$$

TILLY

The office that day

Everything else NWS St. Louis, MO issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 9, 2:46 AM CDT	Flash Flood Warning	LSX	Adams	6 hr
Apr 9, 3:00 AM CDT	Severe Thunderstorm Warning	LSX	Adams, Pike	33 min
Apr 9, 3:44 AM CDT	Severe Thunderstorm Warning	LSX	Calhoun, Pike	31 min
Apr 9, 5:08 AM CDT	Severe Thunderstorm Warning	LSX	Jersey, Madison	22 min
Apr 9, 5:21 AM CDT	Severe Thunderstorm Warning	LSX	Fayette, Montgomery	39 min
Apr 9, 5:25 AM CDT	Severe Thunderstorm Warning	LSX	Macoupin, Madison	35 min
Apr 9, 5:41 AM CDT	Severe Thunderstorm Warning	LSX	Bond, Madison	49 min
Apr 9, 5:44 AM CDT	Areal Flood Advisory	LSX	Calhoun, Jersey, Macoupin, Madison	3 hr
Apr 9, 6:43 AM CDT	Severe Thunderstorm Warning	LSX	Fayette, Marion	32 min
Apr 9, 10:42 AM CDT	River Flood Warning	LSX	Adams	32 days

Nearby

Severe Thunderstorm Warnings in Illinois, 2011 Every severe thunderstorm warning in 2011

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.