Alert archive / Missouri / Severe Thunderstorm Warnings in 2001

Severe Thunderstorm Warning 124, NWS St. Louis, MO

July 18, 2001Jefferson County, Missouri

NWS St. Louis, MO issued this severe thunderstorm warning at Jul 18, 2001, 1:59 PM CDT for Jefferson County, Missouri. It was in force for 46 min. 2 reports came from inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties, with what was reported inside it.

The facts

Issued: Jul 18, 2001, 1:59 PM CDT (18:59 UTC)
Expired: Jul 18, 2001, 2:45 PM CDT
In force: 46 min
Issued by: NWS St. Louis, MO
Area: Whole counties; the outline is the Mesonet’s reconstruction

County Jefferson County, MO

The radar

The St Louis radar (KLSX), 39 km from the middle of the area, began a volume at 18:59 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 18, 2:05 PM CDT	Thunderstorm Wind 55 E	Cedar Hill, MO
Jul 18, 2:15 PM CDT	Thunderstorm Wind 55 E	Hillsboro, MO

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
Jul 18, 1:15 PM CDT	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 7.0 hours before the alert went out and 263 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: 3296 J/kg
Mixed-layer CIN: -30 J/kg
Mixed-layer LCL: 521 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: -16 m²/s²
0-3 km storm-relative helicity: 53 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 3.9

Open this sounding in Storm Lab

The text

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

000 
WUUS53 KLSX 181900
SVRSTL

MOC099-181945-

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
159 PM CDT WED JUL 18 2001

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHERN JEFFERSON COUNTY IN EAST CENTRAL MISSOURI

* UNTIL 245 PM CDT

* AT 159 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM OVER CEDAR HILL...MOVING EAST AT 35 MPH.

* LOCATIONS IN THE PATH...
  PEVELY
  BARNHART
  HERCULANEUM
  CRYSTAL CITY

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

THE PRIMARY THREAT POSED BY THIS STORM IS DAMAGING WINDS. MOVE
QUICKLY TO THE INTERIOR PORTION OF A STURDY SHELTER...AND STAY AWAY
FROM OUTSIDE WALLS AND WINDOWS.

LAT...LON 3845 9075 3819 9075 3816 9038 3843 9036
          3848 9055

RP

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 17, 7:58 PM CDT	Severe Thunderstorm Warning	LSX	Saint Louis, City of Saint Louis	47 min
Jul 17, 8:48 PM CDT	Severe Thunderstorm Warning	LSX	City of Saint Louis	27 min
Jul 18, 1:01 PM CDT	Severe Thunderstorm Warning	LSX	Warren	44 min
Jul 18, 1:11 PM CDT	Severe Thunderstorm Warning	LSX	Franklin	49 min
Jul 18, 2:09 PM CDT	Severe Thunderstorm Warning	LSX	Jefferson	51 min
Jul 18, 2:35 PM CDT	Severe Thunderstorm Warning	LSX	Sainte Genevieve	40 min

Nearby

Severe Thunderstorm Warnings in Missouri, 2001 Every severe thunderstorm warning in 2001

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.