Alert archive / Illinois / Severe Thunderstorm Warnings in 2013

Severe Thunderstorm Warning 13, NWS St. Louis, MO

April 10, 2013Macoupin County, Madison County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Apr 10, 2013, 4:20 PM CDT for Macoupin County, Madison County, Illinois. It was in force for 40 min. 5 reports 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 10, 2013, 4:20 PM CDT (21:20 UTC)
Expired: Apr 10, 2013, 5:00 PM CDT
In force: 40 min
Issued by: NWS St. Louis, MO
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Macoupin County, IL, Madison County, IL

The radar

The St Louis radar (KLSX), 59 km from the middle of the area, began a volume at 21:23 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 10, 4:21 PM CDT	TSTM WND GST 60	5 W Bunker Hill, IL	TOPS OF NUMEROUS TREES BROKEN
Apr 10, 4:23 PM CDT	HAIL 0.25	Godfrey, IL
Apr 10, 4:23 PM CDT	HAIL 0.88	Godfrey, IL
Apr 10, 4:26 PM CDT	HAIL 0.88	Godfrey, IL	HAIL SIZES RANGED FROM PEAS TO NICKELS.
Apr 10, 4:40 PM CDT	HAIL 1.75	4 W Bunker Hill, 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 10, 1:46 PM CDT	Tornado Watch	SPC	7 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 9.3 hours before the alert went out and 182 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: 2649 J/kg
Mixed-layer CIN: -30 J/kg
Mixed-layer LCL: 701 m above ground
0-6 km bulk shear: 43 kt
0-1 km storm-relative helicity: 219 m²/s²
0-3 km storm-relative helicity: 219 m²/s²
Significant tornado parameter: 2.6
Supercell composite: 15.4

Open this sounding in Storm Lab

The text

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

582 
WUUS53 KLSX 102120
SVRLSX
ILC117-119-102200-
/O.NEW.KLSX.SV.W.0013.130410T2120Z-130410T2200Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
420 PM CDT WED APR 10 2013

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHEASTERN MACOUPIN COUNTY IN SOUTHWEST ILLINOIS...
  NORTHWESTERN MADISON COUNTY IN SOUTHWEST ILLINOIS...

* UNTIL 500 PM CDT

* AT 419 PM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR GODFREY...
  AND MOVING NORTHEAST AT 45 MPH.

  HAZARD...QUARTER SIZE HAIL AND 60 MPH WIND GUSTS.

  SOURCE...RADAR INDICATED.

  IMPACT...HAIL DAMAGE TO VEHICLES AND CROPS IS EXPECTED. EXPECT WIND
           DAMAGE TO ROOFS...SIDING AND TREES.

* LOCATIONS IMPACTED INCLUDE...
  GILLESPIE...DORSEY...BUNKER HILL...WILSONVILLE...BENLD...
  FOSTERBURG...ROYAL LAKES...PRUETT...DORCHESTER...HORNSBY AND
  ATWATER.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO WATCH REMAINS IN EFFECT FOR THE WARNED AREA. TORNADOES CAN
DEVELOP QUICKLY FROM SEVERE THUNDERSTORMS. ALTHOUGH ONE IS 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.

FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
BUILDING.

&&

LAT...LON 3888 9016 3889 9019 3891 9022 3892 9027
      3898 9028 3900 9026 3900 9014 3935 8971
      3912 8970
TIME...MOT...LOC 2120Z 230DEG 37KT 3897 9016

HAIL...1.00IN
WIND...60MPH

$$

CARNEY

1 follow-up statement

535 
WWUS53 KLSX 102136
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
436 PM CDT WED APR 10 2013

ILC117-119-102200-
/O.CON.KLSX.SV.W.0013.000000T0000Z-130410T2200Z/
MACOUPIN IL-MADISON IL-
436 PM CDT WED APR 10 2013

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR NORTHWESTERN
MADISON AND SOUTHEASTERN MACOUPIN COUNTIES UNTIL 500 PM CDT...

AT 432 PM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR BRIGHTON...AND
MOVING NORTHEAST AT 40 MPH.

HAZARD...GOLF BALL SIZE HAIL AND 60 MPH WIND GUSTS.

SOURCE...TRAINED WEATHER SPOTTERS.

IMPACT...PEOPLE AND ANIMALS OUTDOORS WILL BE INJURED. EXPECT HAIL
         DAMAGE TO ROOFS...SIDING...WINDOWS...VEHICLES AND CROPS.
         EXPECT WIND DAMAGE TO ROOFS...SIDING AND TREES.

LOCATIONS IMPACTED INCLUDE...
GILLESPIE...BUNKER HILL...WILSONVILLE...BENLD...PRUETT...ROYAL
LAKES...DORCHESTER...HORNSBY AND ATWATER.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A TORNADO WATCH REMAINS IN EFFECT FOR THE WARNED AREA. TORNADOES CAN
DEVELOP QUICKLY FROM SEVERE THUNDERSTORMS. ALTHOUGH ONE IS 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.

THIS STORM IS PRODUCING LARGE HAIL. SEEK SHELTER NOW INSIDE A STURDY
STRUCTURE AND STAY AWAY FROM WINDOWS.

&&

LAT...LON 3888 9016 3889 9019 3891 9022 3892 9027
      3898 9028 3900 9026 3900 9014 3935 8971
      3912 8970
TIME...MOT...LOC 2136Z 228DEG 33KT 3906 9007

HAIL...1.75IN
WIND...60MPH

$$

CARNEY

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 10, 3:16 PM CDT	Severe Thunderstorm Warning	LSX	Jersey, Madison	44 min
Apr 10, 3:19 PM CDT	Severe Thunderstorm Warning	LSX	Randolph	41 min
Apr 10, 3:26 PM CDT	Severe Thunderstorm Warning	LSX	Randolph	49 min
Apr 10, 4:08 PM CDT	Severe Thunderstorm Warning	LSX	Jersey, Macoupin	52 min
Apr 10, 4:38 PM CDT	Severe Thunderstorm Warning	LSX	Washington	37 min
Apr 10, 4:43 PM CDT	Tornado Warning	LSX	Washington	17 min
Apr 10, 4:48 PM CDT	Severe Thunderstorm Warning	LSX	Macoupin, Montgomery	42 min
Apr 10, 4:59 PM CDT	Severe Thunderstorm Warning	LSX	Marion	46 min

Nearby

Severe Thunderstorm Warnings in Illinois, 2013 Every severe thunderstorm warning in 2013

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.