Alert archive / Illinois / Severe Thunderstorm Warnings in 2000

Severe Thunderstorm Warning 49, NWS St. Louis, MO

April 7, 2000Washington County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Apr 7, 2000, 2:50 PM CDT for Washington County, Illinois. It was in force for 55 min. 3 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued: Apr 7, 2000, 2:50 PM CDT (19:50 UTC)
Expired: Apr 7, 2000, 3:45 PM CDT
In force: 55 min
Issued by: NWS St. Louis, MO
Area: Whole counties

County Washington County, IL

The radar

The St Louis radar (KLSX), 117 km from the middle of the area, began a volume at 19:50 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 7, 2:55 PM CDT	Hail 1.75	Okawville, IL
Apr 7, 3:15 PM CDT	Hail 1.5	Hoyleton, IL
Apr 7, 3:46 PM CDT	Hail 1.25	Nashville, IL	Off duty NWS personnel reported 1 1/4 inch hail near Nashville.

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

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 7, 2:15 PM CDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 7.8 hours before the alert went out and 212 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: 935 m above ground
0-6 km bulk shear: 62 kt
0-1 km storm-relative helicity: 216 m²/s²
0-3 km storm-relative helicity: 319 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

311 
WUUS53 KLSX 071950
SVRSTL
ILC189-072045-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
250 PM CDT FRI APR 7 2000

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHERN WASHINGTON COUNTY ILLINOIS IN SOUTH CENTRAL ILLINOIS

* UNTIL 345 PM CDT

* AT 247 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM ALONG THE WASHINGTON CLINTON COUTNY LINE NORTH
  OF OKAWVILLE... MOVING EAST AT 40 MPH.

* LOCATIONS THAT WILL BE AFFECTED...
  OKAWVILLE
  COVINGTON



THE PRIMARY SEVERE WEATHER THREAT IS DAMAGING HAIL. LARGE HAIL CAN
CAUSE EXTENSIVE PROPERTY DAMAGE AN SERIOUS INJURY TO PEOPLE CAUGHT
OUTDOORS. MOVE INSIDE A STURDY BUILDING IMMEDIATELY.




GKS/FG

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 7, 12:07 AM CDT	Severe Thunderstorm Warning	LSX	Madison, Saint Clair	53 min
Apr 7, 7:01 AM CDT	Severe Thunderstorm Warning	LSX	Jersey	34 min
Apr 7, 7:49 AM CDT	Severe Thunderstorm Warning	LSX	Macoupin, Madison	46 min
Apr 7, 8:10 AM CDT	Severe Thunderstorm Warning	LSX	Montgomery	50 min
Apr 7, 8:32 AM CDT	Severe Thunderstorm Warning	LSX	Fayette	48 min
Apr 7, 2:20 PM CDT	Severe Thunderstorm Warning	LSX	Saint Clair	55 min
Apr 7, 2:43 PM CDT	Severe Thunderstorm Warning	LSX	Clinton	62 min
Apr 7, 2:51 PM CDT	Severe Thunderstorm Warning	LSX	Monroe	54 min
Apr 7, 3:10 PM CDT	Severe Thunderstorm Warning	LSX	Marion	50 min
Apr 7, 3:13 PM CDT	Severe Thunderstorm Warning	LSX	Randolph, Saint Clair	47 min
Apr 7, 3:38 PM CDT	Severe Thunderstorm Warning	LSX	Clinton, Washington	37 min

Nearby

Severe Thunderstorm Warnings in Illinois, 2000 Every severe thunderstorm warning in 2000

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.