Alert archive / Illinois / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 151, NWS St. Louis, MO

July 23, 2017Madison County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Jul 23, 2017, 3:14 AM CDT for Madison County, Illinois. It was in force for 46 min. 7 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: Jul 23, 2017, 3:14 AM CDT (08:14 UTC)
Expired: Jul 23, 2017, 4:00 AM CDT
In force: 46 min
Issued by: NWS St. Louis, MO
Area: Storm-based polygon
Hail: 1.0 in
Wind: 70.0 mph

County Madison County, IL

The radar

The St Louis radar (KLSX), 62 km from the middle of the area, began a volume at 08:17 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
Jul 23, 3:17 AM CDT	TSTM WND GST 65	Granite City, IL
Jul 23, 3:30 AM CDT	TSTM WND DMG	2 Nnw Saint Jacob, IL	NUMEROUS TREES DOWNED.
Jul 23, 3:30 AM CDT	TSTM WND DMG	Glen Carbon, IL	TREE SNAPPED OF UNKNOWN SIZE.
Jul 23, 3:33 AM CDT	TSTM WND GST 61	1 Nnw Bethalto, IL
Jul 23, 3:47 AM CDT	TSTM WND DMG	3 Ese Marine, IL	TURKEY TRACTOR MOVED 10 FEET AND SPLIT IN HALF. ALL 14 TURKEYS SURVIVED. ADDITIONAL WIND DAMAGE TO CROPS AND TREES. LOCATION APPROXIMATE. TIME ESTIMATED FROM RADAR AND WRITTEN DESCRIPTION.
Jul 23, 3:53 AM CDT	HAIL 0.75	Saint Jacob, IL
Jul 23, 3:56 AM CDT	TSTM WND DMG	St. Jacob, IL	LARGE TREE LIMB BLOWN DOWN.

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
Jul 23, 12:38 AM CDT	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 8.2 hours before the alert went out and 190 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: 2392 J/kg
Mixed-layer CIN: -34 J/kg
Mixed-layer LCL: 1185 m above ground
0-6 km bulk shear: 26 kt
0-1 km storm-relative helicity: 51 m²/s²
0-3 km storm-relative helicity: 233 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 6.0

Open this sounding in Storm Lab

The text

As transmitted.

202 
WUUS53 KLSX 230814
SVRLSX
ILC119-230900-
/O.NEW.KLSX.SV.W.0151.170723T0814Z-170723T0900Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service St Louis MO
314 AM CDT SUN JUL 23 2017

The National Weather Service in St Louis has issued a

* Severe Thunderstorm Warning for...
  Madison County in southwestern Illinois...

* Until 400 AM CDT.

* At 314 AM CDT, a severe thunderstorm was located over Hartford,
  moving east at 45 mph.

  HAZARD...70 mph wind gusts and quarter size hail. 

  SOURCE...Radar indicated. 

  IMPACT...Hail damage to vehicles is expected. Expect considerable 
           tree damage. Wind damage is also likely to mobile homes, 
           roofs, and outbuildings. 

* Locations impacted include...
  Granite City, Alton, Collinsville, Edwardsville, Glen Carbon, Wood
  River, Highland, Troy, Bethalto, Maryville, Pontoon Beach,
  Staunton, Madison, Venice, East Alton, Fairmont City, South Roxana,
  Roxana, Hartford and St. Jacob.

This includes the following highways...
 Interstate 70 in Illinois between exits 21 and 30.
 Interstate 55 in Illinois between exits 23 and 37.

This also includes  Horseshoe Lake State Park.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3866 9018 3872 9021 3875 9018 3877 9017
      3880 9012 3883 9011 3899 9015 3900 8994
      3900 8964 3888 8964 3887 8960 3867 8960
TIME...MOT...LOC 0814Z 269DEG 37KT 3880 9013 

HAIL...1.00IN
WIND...70MPH
 
$$

Carney

1 follow-up statement

978 
WWUS53 KLSX 230842
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
342 AM CDT SUN JUL 23 2017

ILC119-230900-
/O.CON.KLSX.SV.W.0151.000000T0000Z-170723T0900Z/
Madison IL-
342 AM CDT SUN JUL 23 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 400 AM CDT
FOR MADISON COUNTY IN SOUTHWESTERN ILLINOIS...

At 341 AM CDT, a severe thunderstorm was located near Edwardsville,
moving east at 35 mph.

HAZARD...70 mph wind gusts and half dollar size hail. 

SOURCE...Radar indicated. At 333 AM a wind gust of 61 mph was 
         reported at Alton Regional Airport. 

IMPACT...Hail damage to vehicles is expected. Expect considerable 
         tree damage. Wind damage is also likely to mobile homes, 
         roofs, and outbuildings. 

Locations impacted include...
Granite City, Alton, Collinsville, Edwardsville, Glen Carbon, Wood
River, Highland, Troy, Bethalto, Maryville, Pontoon Beach, Staunton,
Madison, Venice, East Alton, Fairmont City, South Roxana, Roxana,
Hartford and St. Jacob.

This also includes  Horseshoe Lake State Park.
 
This includes the following highways...
 Interstate 70 in Illinois between exits 21 and 30.
 Interstate 55 in Illinois between exits 23 and 37.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3866 9018 3872 9021 3875 9018 3877 9017
      3880 9012 3883 9011 3899 9015 3900 8994
      3900 8964 3888 8964 3887 8960 3867 8960
TIME...MOT...LOC 0841Z 270DEG 29KT 3880 8989 

HAIL...1.25IN
WIND...70MPH
 
$$

Carney

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 22, 10:33 PM CDT	Special Weather Statement	LSX	Saint Clair	42 min
Jul 22, 11:11 PM CDT	Special Weather Statement	LSX	Madison	49 min
Jul 22, 11:34 PM CDT	Special Weather Statement	LSX	Saint Clair	41 min
Jul 23, 2:17 AM CDT	Severe Thunderstorm Warning	LSX	Pike	43 min
Jul 23, 2:48 AM CDT	Severe Thunderstorm Warning	LSX	Calhoun, Greene, Jersey, Madison, Pike	42 min
Jul 23, 3:19 AM CDT	Severe Thunderstorm Warning	LSX	Saint Clair	41 min
Jul 23, 3:25 AM CDT	Severe Thunderstorm Warning	LSX	Greene, Jersey, Macoupin, Montgomery	50 min
Jul 23, 3:48 AM CDT	Severe Thunderstorm Warning	LSX	Bond, Clinton, Madison, Saint Clair, Washington	42 min
Jul 23, 4:08 AM CDT	Severe Thunderstorm Warning	LSX	Fayette, Macoupin, Montgomery	67 min
Jul 23, 4:24 AM CDT	Severe Thunderstorm Warning	LSX	Bond, Clinton, Fayette, Marion, Washington	52 min
Jul 23, 4:30 PM CDT	Severe Thunderstorm Warning	LSX	Greene, Macoupin	30 min
Jul 23, 5:01 PM CDT	Special Weather Statement	LSX	Macoupin	44 min
Jul 23, 5:14 PM CDT	Special Weather Statement	LSX	Pike	46 min
Jul 23, 6:52 PM CDT	Special Weather Statement	LSX	Jersey	53 min

Nearby

Severe Thunderstorm Warnings in Illinois, 2017 Every severe thunderstorm warning in 2017

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.