Alert archive / Illinois / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 154, NWS St. Louis, MO

July 23, 20175 counties in Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Jul 23, 2017, 3:48 AM CDT for 5 counties in Illinois. It was in force for 42 min. 2 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, 3:48 AM CDT (08:48 UTC)
Expired: Jul 23, 2017, 4:30 AM CDT
In force: 42 min
Issued by: NWS St. Louis, MO
Area: Storm-based polygon
Hail: 1.25 in
Wind: 70.0 mph

Counties Bond County, IL, Clinton County, IL, Madison County, IL, Saint Clair County, IL, Washington County, IL

The radar

The St Louis radar (KLSX), 102 km from the middle of the area, began a volume at 08:47 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, 4:15 AM CDT	TSTM WND DMG	Carlyle, IL	TREE DOWN
Jul 23, 4:20 AM CDT	TSTM WND DMG	Mulberry Grove, IL	LARGE LIMBS 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, 8.8 hours before the alert went out and 177 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.

295 
WUUS53 KLSX 230848
SVRLSX
ILC005-027-119-163-189-230930-
/O.NEW.KLSX.SV.W.0154.170723T0848Z-170723T0930Z/

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

The National Weather Service in St Louis has issued a

* Severe Thunderstorm Warning for...
  Clinton County in south central Illinois...
  Bond County in south central Illinois...
  Washington County in south central Illinois...
  Eastern Madison County in southwestern Illinois...
  Northeastern St. Clair County in southwestern Illinois...

* Until 430 AM CDT.

* At 348 AM CDT, severe thunderstorms were located along a line
  extending from near Livingston to near St. Jacob to near New
  Memphis, moving east at 35 mph.

  HAZARD...70 mph wind gusts and half dollar 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...
  Highland, Greenville, Breese, New Baden, Carlyle, Nashville,
  Centralia, Trenton, Aviston, Okawville, St. Rose, Germantown,
  Albers, Wamac, Beckemeyer, Livingston, Pocahontas, Alhambra,
  Irvington and Mulberry Grove.

This includes the following highways...
 Interstate 70 in Illinois between exits 24 and 52.
 Interstate 55 in Illinois near exit 37.
 Interstate 64 in Illinois between exits 27 and 61.

This also includes  Carlyle Lake Recreational Area.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 3836 8977 3866 8973 3900 8978 3900 8959
      3903 8959 3903 8925 3874 8925 3874 8914
      3828 8915
TIME...MOT...LOC 0848Z 273DEG 32KT 3895 8980 3868 8972 3846 8975 

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

Carney

1 follow-up statement

444 
WWUS53 KLSX 230912
SVSLSX

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

ILC005-027-119-163-189-230930-
/O.CON.KLSX.SV.W.0154.000000T0000Z-170723T0930Z/
Clinton IL-Bond IL-Washington IL-Madison IL-St. Clair IL-
412 AM CDT SUN JUL 23 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 430 AM CDT
FOR CLINTON...BOND AND WASHINGTON COUNTIES IN SOUTH CENTRAL
ILLINOIS...EASTERN MADISON AND NORTHEASTERN ST. CLAIR COUNTIES IN
SOUTHWESTERN ILLINOIS...

At 411 AM CDT, severe thunderstorms were located along a line
extending from near Reno to near St. Rose to near Okawville, moving
east at 35 mph.

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

SOURCE...Trained weather spotters. 

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...
Highland, Greenville, Breese, New Baden, Carlyle, Nashville,
Centralia, Trenton, Aviston, Okawville, St. Rose, Germantown, Albers,
Wamac, Beckemeyer, Livingston, Pocahontas, Alhambra, Irvington and
Mulberry Grove.

This also includes  Carlyle Lake Recreational Area.
 
This includes the following highways...
 Interstate 70 in Illinois between exits 24 and 52.
 Interstate 55 in Illinois near exit 37.
 Interstate 64 in Illinois between exits 27 and 61.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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

&&

LAT...LON 3836 8977 3866 8973 3900 8978 3900 8959
      3903 8959 3903 8925 3874 8925 3874 8914
      3828 8915
TIME...MOT...LOC 0911Z 273DEG 32KT 3894 8956 3867 8948 3845 8951 

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, 3:14 AM CDT	Severe Thunderstorm Warning	LSX	Madison	46 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, 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.