Alert archive / Missouri / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 69, NWS St. Louis, MO

May 18, 1997Knox County, Scotland County, Missouri

NWS St. Louis, MO issued this severe thunderstorm warning at May 18, 1997, 9:20 PM CDT for Knox County, Scotland County, Missouri. It was in force for 40 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: May 18, 1997, 9:20 PM CDT (02:20 UTC)
Expired: May 18, 1997, 10:00 PM CDT
In force: 40 min
Issued by: NWS St. Louis, MO
Area: Whole counties

Counties Knox County, MO, Scotland County, MO

The radar

The Quad Cities radar (KDVN), 197 km from the middle of the area, began a volume at 02:24 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.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
May 18, 5:30 PM CDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 2.3 hours before the alert went out and 202 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: 2339 J/kg
Mixed-layer CIN: -25 J/kg
Mixed-layer LCL: 1544 m above ground
0-6 km bulk shear: 49 kt
0-1 km storm-relative helicity: 145 m²/s²
0-3 km storm-relative helicity: 165 m²/s²
Significant tornado parameter: 1.0
Supercell composite: 9.0

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KSTL 190220 RRA
SVRSTL
MOC103-199-190300-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
920 PM CDT SUN MAY 18 1997
 
THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 1000 PM CDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN NORTHEAST MISSOURI
 
   ...KNOX COUNTY...SOUTHERN SCOTLAND COUNTY
 
AT 920 PM...NATIONAL WEATHER SERVICE DOPPLAR RADAR WAS DETECTING TWO
SEVERE THUNDERSTORMS. ONE WAS NEAR GREENSBURG AND WAS MOVING TO THE
NORTHEAST AT 25 MPH. IT WILL MOVE THROUGH GREENSBURG AND RUTLEDGE BY 940
PM. THE SECOND STORM WAS 5 MILES SOUTHWEST OF EDINA AND WAS MOVING TO
THE EAST AT 30 MPH. IT WILL MOVE THR$OUGH EDINA AND KNOX CITY.
 
THIS STORM HAS A HISTORY OF DAMAGING HAIL. STAY INSIDE AND AWAY
FROM WINDOWS.
 
GKS/AMS

The office that day

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

Issued	Product	Office	Counties	Lasted
May 18, 8:02 PM CDT	Severe Thunderstorm Warning	LSX	Scotland	43 min
May 18, 8:22 PM CDT	Severe Thunderstorm Warning	LSX	Clark	53 min
May 18, 8:40 PM CDT	Severe Thunderstorm Warning	LSX	Knox	50 min
May 18, 9:35 PM CDT	Severe Thunderstorm Warning	LSX	Lewis	55 min
May 18, 10:03 PM CDT	Severe Thunderstorm Warning	LSX	Knox	42 min
May 18, 10:21 PM CDT	Flash Flood Warning	LSX	Knox	3 hr
May 18, 10:49 PM CDT	Severe Thunderstorm Warning	LSX	Knox	41 min

Nearby

Severe Thunderstorm Warnings in Missouri, 1997 Every severe thunderstorm warning in 1997

Sources

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