Alert archive / Missouri / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 35, NWS St. Louis, MO

April 30, 1997Knox County, Scotland County, Missouri

NWS St. Louis, MO issued this severe thunderstorm warning at Apr 30, 1997, 11:56 AM CDT for Knox County, Scotland County, Missouri. It was in force for 49 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
Apr 30, 1997, 11:56 AM CDT (16:56 UTC)
Expired
Apr 30, 1997, 12:45 PM CDT
In force
49 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 16:58 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 nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 4.9 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-pSkew-T log-p diagram, Davenport, at 12:00Z on 1997-04-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Davenport, at 12:00Z on 1997-04-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 75 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
1366 m above ground
0-6 km bulk shear
54 kt
0-1 km storm-relative helicity
75 m²/s²
0-3 km storm-relative helicity
180 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.

000 
TTAA00 KSTL 301657 RRA
SVRSTL
MOC103-199-301745-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
1156 AM CDT WED APR 30 1997
 
THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 1245 PM CDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN NORTHEAST MISSOURI
 
   ...NORTHWESTERN KNOX COUNTY...SCOTLAND COUNTY
 
AT 1155 PM...RADAR INDICATED A SEVERE THUNDERSTORM OVER EASTERN ADAIR
COUNTY MOVING NORTHEAST AT 45 MPH.
 
TOWNS IN THE PATH OF THIS STORM ARE BIBLE GROVE...GREENSBURG AND
MEMPHIS.  THIS STORM WILL PRODUCE STRONG AND GUSTY WIND GREATER THAN
55 MPH AND HAIL AROUND AN INCH IN DIAMETER.
 
THIS IS A DANGEROUS STORM! BE PREPARED FOR DAMAGING WINDS...HAIL
AND DEADLY LIGHTNING. STAY INSIDE AND AWAY FROM WINDOWS.
 
 
LEWIS

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

In the hours before

Special weather statement, Apr 30, 7:00 AM CDT, 4 hours 56 minutes before
MOZ042-041-050-010-048-072-062-059-084-018-019-052-085-027-047-
051-034-049-036-035-099-061-075-074-063-064-009-026-060-073-ILZ095-
064-096-098-069-065-058-099-059-100-070-102-060-097-079-101-074-
MOZ065-291600-

SEVERE WEATHER OUTLOOK
NATIONAL WEATHER SERVICE ST LOUIS MO
600 AM CST WED APR 30 1997

THIS OUTLOOK COVERS THE COUNTY WARNING AREA OF THE NWS OFFICE
IN ST LOUIS.  AREAS INCLUDED ARE PARTS OF CENTRAL...NORTHEAST AND
EAST CENTRAL MISSOURI...AND SOUTHWEST ILLINOIS.

THERE IS A MODERATE RISK OF SEVERE WEATHER THIS AFTERNOON OVER
EXTREME EASTERN MISSOURI AND CENTRAL AND SOUTHERN ILLINOIS. THIS IS
AN AREA GENERALLY SOUTH AND EAST OF A LINE FROM HILLSBORO ILLINOIS
TO ST. LOUIS TO CAPE GIRARDEAU.

THERE IS ALSO A SLIGHT RISK OF SEVERE WEATHER ACROSS MUCH OF THE
EASTERN HALF OF MISSOURI AND NORTHERN ILLINOIS. THE SLIGHT RISK AREA
COVERS THE REST OF THE ST. LOUIS COUNTY WARNING AREA.

A DEEP LOW PRESSURE SYSTEM WILL FROM KANSAS INTO NORTHEAST ILLINOIS
BY THIS EVENING. WITH THIS LOW...A STRONG COLD FRONT WILL MOVE FROM
WEST TO EAST ACROSS MISSOURI TODAY. SHOWERS AND THUNDERSTORMS WILL
DEVELOP ALONG AND AHEAD OF THE FRONT. WITH THE THE EXPECTED SHEAR
AND INSTABILITY OF THE ATMOSPHERE AS THE FRONT PASSES...SOME OF THE
STORMS MAY BE SEVERE.

STORM SPOTTER GROUPS AND EMERGENCY MANAGERS SHOULD KEEP ADVISED OF
THE LATEST FORECAST FOR POSSIBLE SKYWARN ACTION FROM LATE THIS
MORNING THROUGH THE EARLY EVENING.

AMS
Special weather statement, Apr 30, 11:33 AM CDT, 23 minutes before
MOZ042-041-050-010-048-072-062-059-084-018-019-052-085-027-047-
051-034-049-036-035-099-061-075-074-063-064-009-026-060-073-ILZ095-
064-096-098-069-065-058-099-059-100-070-102-060-097-079-101-074-
MOZ065-291600-

SEVERE WEATHER OUTLOOK
NATIONAL WEATHER SERVICE ST LOUIS MO
1130 AM CST WED APR 30 1997

THIS OUTLOOK COVERS THE COUNTY WARNING AREA OF THE NWS OFFICE
IN ST LOUIS.  AREAS INCLUDED ARE PARTS OF CENTRAL...NORTHEAST AND
EAST CENTRAL MISSOURI...AND SOUTHWEST ILLINOIS.

THERE IS A MODERATE RISK OF SEVERE WEATHER THIS AFTERNOON OVER
EXTREME EASTERN MISSOURI AND CENTRAL AND NORTHERN ILLINOIS. THIS IS
AN AREA GENERALLY NORTH AND EAST OF A LINE FROM SALEM ILLINOIS
TO ST. LOUIS NORTHWEST ALONG THE MISSISSIPPI RIVER TO THE IOWA BORDER.

THERE IS ALSO A SLIGHT RISK OF SEVERE WEATHER ACROSS MUCH OF THE
EASTERN HALF OF MISSOURI AND NORTHERN ILLINOIS. THE SLIGHT RISK AREA
COVERS THE REST OF THE ST. LOUIS COUNTY WARNING AREA.

A LOW PRESSURE SYSTEM IS MOVING RAPIDLY NORTHEAST ACROSS NORTHERN
MISSOURI THIS MORNING...AND WILL MOVE INTO NORTHEASTERN ILLINOIS BY
THIS EVENING. A COLD FRONT WILL SWEEP EASTWARD ACROSS EASTERN
MISSOURI THIS AFTERNOON...TRIGGERING STRONG THUNDERSTORMS. SOME \OF
THESE STORMS MAY BECOME SEVERE.

STORM SPOTTER GROUPS AND EMERGENCY MANAGERS SHOULD KEEP ADVISED OF
THE LATEST FORECAST FOR POSSIBLE SKYWARN ACTION FROM LATE THIS
MORNING THROUGH THE EARLY EVENING.

WDB

Nearby

Severe Thunderstorm Warnings in Missouri, 1997Every 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.