Alert archive / Illinois / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 78, NWS St. Louis, MO

May 10, 2017Jersey County, Macoupin County, Madison County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at May 10, 2017, 9:31 PM CDT for Jersey County, Macoupin County, Madison County, Illinois. It was in force for 27 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: May 10, 2017, 9:31 PM CDT (02:31 UTC)
Expired: May 10, 2017, 9:58 PM CDT
In force: 27 min
Issued by: NWS St. Louis, MO
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Jersey County, IL, Macoupin County, IL, Madison County, IL

The radar

The St Louis radar (KLSX), 66 km from the middle of the area, began a volume at 02:34 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
May 10, 9:34 PM CDT	HAIL 0.25	Brighton, IL

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

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 2.5 hours before the alert went out and 176 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: 442 J/kg
Mixed-layer CIN: -26 J/kg
Mixed-layer LCL: 1634 m above ground
0-6 km bulk shear: 38 kt
0-1 km storm-relative helicity: 104 m²/s²
0-3 km storm-relative helicity: 140 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 3.0

Open this sounding in Storm Lab

The text

As transmitted.

122 
WUUS53 KLSX 110231
SVRLSX
ILC083-117-119-110315-
/O.NEW.KLSX.SV.W.0078.170511T0231Z-170511T0315Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service St Louis MO
931 PM CDT WED MAY 10 2017

The National Weather Service in St Louis has issued a

* Severe Thunderstorm Warning for...
  Northern Madison County in southwestern Illinois...
  Southern Macoupin County in southwestern Illinois...
  Southeastern Jersey County in southwestern Illinois...

* Until 1015 PM CDT.

* At 930 PM CDT, a severe thunderstorm was located over Brighton,
  moving east at 40 mph.

  HAZARD...60 mph wind gusts and quarter size hail. 

  SOURCE...Radar indicated. 

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees. 

* Locations impacted include...
  Godfrey, Staunton, Gillespie, Brighton, Mount Olive, Bunker Hill,
  Benld, Worden, Livingston, Shipman, Wilsonville, Sawyerville, Mount
  Clare, East Gillespie, Eagarville, Prairietown, Dorsey, Piasa,
  White City and Williamson.

This includes Interstate 55 in Illinois between exits 33 and 44.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3896 9028 3914 9028 3919 8970 3890 8970
TIME...MOT...LOC 0230Z 270DEG 33KT 3906 9018 

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

Britt

2 follow-up statements

908 
WWUS53 KLSX 110244
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
944 PM CDT WED MAY 10 2017

ILC083-110252-
/O.CAN.KLSX.SV.W.0078.000000T0000Z-170511T0315Z/
Jersey IL-
944 PM CDT WED MAY 10 2017

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN JERSEY COUNTY IS
CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

LAT...LON 3895 9015 3907 9014 3915 9015 3919 8970
      3890 8970
TIME...MOT...LOC 0242Z 273DEG 33KT 3902 9003 

$$

ILC117-119-110315-
/O.CON.KLSX.SV.W.0078.000000T0000Z-170511T0315Z/
Madison IL-Macoupin IL-
944 PM CDT WED MAY 10 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1015 PM CDT
FOR NORTHEASTERN MADISON AND SOUTHERN MACOUPIN COUNTIES IN
SOUTHWESTERN ILLINOIS...

At 942 PM CDT, a severe thunderstorm was located near Dorsey, moving
east at 40 mph.

HAZARD...60 mph wind gusts and quarter size hail. 

SOURCE...Radar indicated. 

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees. 

Locations impacted include...
Staunton, Gillespie, Brighton, Mount Olive, Bunker Hill, Benld,
Worden, Livingston, Shipman, Wilsonville, Sawyerville, Mount Clare,
East Gillespie, Eagarville, Prairietown, Dorsey, Piasa, White City,
Williamson and Royal Lakes.

This includes Interstate 55 in Illinois between exits 33 and 44.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3895 9015 3907 9014 3915 9015 3919 8970
      3890 8970
TIME...MOT...LOC 0242Z 273DEG 33KT 3902 9003 

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

Britt

458 
WWUS53 KLSX 110258
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
958 PM CDT WED MAY 10 2017

ILC117-119-110308-
/O.CAN.KLSX.SV.W.0078.000000T0000Z-170511T0315Z/
Madison IL-Macoupin IL-
958 PM CDT WED MAY 10 2017

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN MADISON AND
SOUTHERN MACOUPIN COUNTIES IN SOUTHWESTERN ILLINOIS IS CANCELLED...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore the warning has been cancelled.

LAT...LON 3895 9015 3907 9014 3915 9015 3919 8970
      3890 8970
TIME...MOT...LOC 0257Z 270DEG 33KT 3902 8984 

$$

Britt

The office that day

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

Issued	Product	Office	Counties	Lasted
May 10, 7:16 PM CDT	Severe Thunderstorm Warning	LSX	Calhoun, Greene, Pike	44 min
May 10, 8:50 PM CDT	Special Weather Statement	LSX	Jersey	25 min
May 10, 9:23 PM CDT	Special Weather Statement	LSX	Jersey	37 min
May 10, 11:33 PM CDT	Flash Flood Warning	LSX	Bond, Fayette, Madison, Marion, Montgomery	6 hr

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.