Alert archive / Illinois / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 97, NWS St. Louis, MO

April 19, 2011Greene County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Apr 19, 2011, 5:42 PM CDT for Greene County, Illinois. It was in force for 34 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Apr 19, 2011, 5:42 PM CDT (22:42 UTC)
Expired: Apr 19, 2011, 6:16 PM CDT
In force: 34 min
Issued by: NWS St. Louis, MO
Area: Storm-based polygon
Hail: 1.75 in
Wind: 70.0 mph

County Greene County, IL

The radar

The St Louis radar (KLSX), 69 km from the middle of the area, began a volume at 22:45 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.

What was reported inside it

Time	Report	Where	Remark
Apr 19, 5:54 PM CDT	HAIL 2.75	Roodhouse, IL

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Apr 19, 1:00 PM CDT	Tornado Watch	SPC	10 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 10.7 hours before the alert went out and 183 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: 453 m above ground
0-6 km bulk shear: 57 kt
0-1 km storm-relative helicity: 189 m²/s²
0-3 km storm-relative helicity: 345 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 2.4

Open this sounding in Storm Lab

The text

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

892 
WUUS53 KLSX 192242
SVRLSX
ILC061-192330-
/O.NEW.KLSX.SV.W.0097.110419T2242Z-110419T2330Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
542 PM CDT TUE APR 19 2011

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  GREENE COUNTY IN SOUTHWEST ILLINOIS...

* UNTIL 630 PM CDT

* AT 541 PM CDT...TRAINED WEATHER SPOTTERS REPORTED A SEVERE
  THUNDERSTORM PRODUCING GOLF BALL SIZE HAIL...AND DESTRUCTIVE WINDS
  IN EXCESS OF 70 MPH.  THIS STORM WAS LOCATED NEAR WHITE HALL...AND
  MOVING EAST AT 40 MPH.

  THIS STORM HAS A HISTORY OF PRODUCING LARGE HAIL AND WIND GUSTS UP 
  TO 75 MPH NEAR ROODHOUSE.

* LOCATIONS IMPACTED INCLUDE...
  GREENFIELD...ATHENSVILLE AND WRIGHTS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO WATCH REMAINS IN EFFECT FOR THE WARNED AREA. TORNADOES CAN
DEVELOP QUICKLY FROM SEVERE THUNDERSTORMS. ALTHOUGH NOT IMMEDIATELY
LIKELY...IF A TORNADO IS SPOTTED...ACT QUICKLY AND MOVE TO A PLACE OF
SAFETY INSIDE A STURDY STRUCTURE...SUCH AS A BASEMENT OR SMALL
INTERIOR ROOM.

&&

LAT...LON 3936 9015 3923 9025 3922 9032 3918 9033
      3919 9058 3913 9061 3918 9061 3921 9060
      3925 9061 3937 9062 3953 9053 3953 9017
TIME...MOT...LOC 2242Z 263DEG 33KT 3944 9036
WIND...HAIL 70MPH 1.75IN

$$

TILLY

1 follow-up statement

668 
WWUS53 KLSX 192316
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
616 PM CDT TUE APR 19 2011

ILC061-192326-
/O.CAN.KLSX.SV.W.0097.000000T0000Z-110419T2330Z/
GREENE IL-
616 PM CDT TUE APR 19 2011

...THE SEVERE THUNDERSTORM WARNING FOR GREENE COUNTY IS CANCELLED...

THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE WARNED
AREA.

ADDITIONAL STRONG THUNDERSTORMS ARE STILL POSSIBLE...AND A TORNADO 
WATCH REMAINS IN EFFECT UNTIL 900 PM. PLEASE REPORT ANY DAMAGE TO 
LOCAL LAW ENFORCEMENT OR THE NATIONAL WEATHER SERVICE.

LAT...LON 3936 9015 3923 9025 3922 9032 3918 9033
      3919 9058 3913 9061 3918 9061 3921 9060
      3925 9061 3937 9062 3953 9053 3953 9017
TIME...MOT...LOC 2316Z 246DEG 45KT 3950 8995

$$

TILLY

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 19, 4:35 AM CDT	Severe Thunderstorm Warning	LSX	Calhoun, Greene, Pike	40 min
Apr 19, 5:14 AM CDT	Severe Thunderstorm Warning	LSX	Greene, Pike	31 min
Apr 19, 6:21 AM CDT	Areal Flood Advisory	LSX	Madison, Monroe, Saint Clair	3 hr
Apr 19, 6:22 AM CDT	Severe Thunderstorm Warning	LSX	Monroe, Randolph, Saint Clair	38 min
Apr 19, 6:26 AM CDT	Severe Thunderstorm Warning	LSX	Madison, Saint Clair	49 min
Apr 19, 6:56 AM CDT	Severe Thunderstorm Warning	LSX	Monroe, Saint Clair	49 min
Apr 19, 7:08 AM CDT	Severe Thunderstorm Warning	LSX	Jersey, Macoupin, Madison, Montgomery	37 min
Apr 19, 7:36 AM CDT	Severe Thunderstorm Warning	LSX	Bond, Macoupin, Madison, Montgomery	39 min
Apr 19, 8:07 AM CDT	Severe Thunderstorm Warning	LSX	Bond, Fayette, Montgomery	38 min
Apr 19, 8:25 AM CDT	Severe Thunderstorm Warning	LSX	Fayette, Marion	29 min
Apr 19, 8:41 AM CDT	Severe Thunderstorm Warning	LSX	Fayette	34 min
Apr 19, 11:18 AM CDT	River Flood Warning	LSX	Calhoun, Greene, Jersey	85 days
Apr 19, 3:46 PM CDT	Severe Thunderstorm Warning	LSX	Pike	44 min
Apr 19, 3:59 PM CDT	Tornado Warning	LSX	Pike	46 min
Apr 19, 4:18 PM CDT	Tornado Warning	LSX	Calhoun, Greene, Pike	42 min
Apr 19, 4:31 PM CDT	Tornado Warning	LSX	Calhoun	44 min
Apr 19, 4:41 PM CDT	Severe Thunderstorm Warning	LSX	Calhoun, Greene, Jersey, Macoupin, Madison	49 min
Apr 19, 4:59 PM CDT	Tornado Warning	LSX	Greene, Pike	46 min
Apr 19, 5:28 PM CDT	Severe Thunderstorm Warning	LSX	Greene, Jersey, Macoupin	47 min
Apr 19, 5:28 PM CDT	Severe Thunderstorm Warning	LSX	Calhoun	47 min
Apr 19, 5:36 PM CDT	Tornado Warning	LSX	Macoupin	39 min
Apr 19, 5:44 PM CDT	Severe Thunderstorm Warning	LSX	Calhoun, Jersey	34 min
Apr 19, 6:01 PM CDT	Tornado Warning	LSX	Montgomery	44 min
Apr 19, 6:05 PM CDT	Tornado Warning	LSX	Macoupin, Montgomery	40 min
Apr 19, 6:12 PM CDT	Severe Thunderstorm Warning	LSX	Calhoun	48 min
Apr 19, 6:14 PM CDT	Severe Thunderstorm Warning	LSX	Jersey, Macoupin, Madison	61 min
Apr 19, 6:31 PM CDT	Tornado Warning	LSX	Montgomery	27 min
Apr 19, 6:56 PM CDT	Severe Thunderstorm Warning	LSX	Bond, Macoupin, Madison, Montgomery	64 min

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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.