Alert archive / Illinois / Severe Thunderstorm Warnings in 2000

Severe Thunderstorm Warning 110, NWS St. Louis, MO

April 20, 2000Fayette County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Apr 20, 2000, 10:27 AM CDT for Fayette County, Illinois. It was in force for 48 min. 1 report 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 20, 2000, 10:27 AM CDT (15:27 UTC)
Expired: Apr 20, 2000, 11:15 AM CDT
In force: 48 min
Issued by: NWS St. Louis, MO
Area: Whole counties

County Fayette County, IL

The radar

The Lincoln radar (KILX), 131 km from the middle of the area, began a volume at 15:28 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 20, 10:40 AM CDT	Thunderstorm Wind 55 E	St Peter, IL	Storm spotters reported a couple of grain bins blown over by thunderstorm wind gusts.

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 20, 10:00 AM CDT	Tornado Watch	SPC	6 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 3.5 hours before the alert went out and 133 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: 595 J/kg
Mixed-layer CIN: -48 J/kg
Mixed-layer LCL: 873 m above ground
0-6 km bulk shear: 54 kt
0-1 km storm-relative helicity: 167 m²/s²
0-3 km storm-relative helicity: 147 m²/s²
Significant tornado parameter: 0.5
Supercell composite: 3.4

Open this sounding in Storm Lab

The text

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

171 
WUUS53 KLSX 201527
SVRSTL
ILC051-201615-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
1027 AM CDT THU APR 20 2000

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  FAYETTE COUNTY IN SOUTH CENTRAL ILLINOIS

* UNTIL 1115 AM CDT

* AT 1025 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  A SEVERE THUNDERSTORM 8 MILES SOUTH OF VANDALIA... MOVING EAST
  NORTHEAST AT 30 MPH.

* LOCATIONS THAT WILL BE AFFECTED...
  ST JAMES
  LOOGOOTEE
  ST ELMO
  BROWNSTOWN



SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND GUSTS IN EXCESS OF 60
MPH...DAMAGING HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN. MOVE
TO AN INTERIOR ROOM ON THE LOWEST FLOOR OR YOUR HOME OR BUSINESS.
HEAVY RAINS FLOOD ROADS QUICKLY SO DO NOT DRIVE INTO AREAS WHERE
WATER COVERS THE ROAD.



TES

The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 19, 8:47 PM CDT	Severe Thunderstorm Warning	LSX	Pike	33 min
Apr 19, 8:57 PM CDT	Severe Thunderstorm Warning	LSX	Calhoun	33 min
Apr 20, 3:46 AM CDT	Severe Thunderstorm Warning	LSX	Adams	49 min
Apr 20, 4:29 AM CDT	Severe Thunderstorm Warning	LSX	Calhoun, Pike	51 min
Apr 20, 4:49 AM CDT	Severe Thunderstorm Warning	LSX	Greene, Jersey	46 min
Apr 20, 5:06 AM CDT	Severe Thunderstorm Warning	LSX	Macoupin	49 min
Apr 20, 7:18 AM CDT	Severe Thunderstorm Warning	LSX	Jersey	42 min
Apr 20, 7:29 AM CDT	Severe Thunderstorm Warning	LSX	Greene	46 min
Apr 20, 8:02 AM CDT	Tornado Warning	LSX	Macoupin	43 min
Apr 20, 8:54 AM CDT	Severe Thunderstorm Warning	LSX	Montgomery	51 min
Apr 20, 9:37 AM CDT	Severe Thunderstorm Warning	LSX	Bond, Clinton, Fayette	48 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.