Alert archive / Missouri / Tornado Warnings in 1999

Tornado Warning 10, NWS St. Louis, MO

April 8, 1999Knox County, Shelby County, Missouri

NWS St. Louis, MO issued this tornado warning at Apr 8, 1999, 5:21 PM CDT for Knox County, Shelby County, Missouri. It was in force for 64 min. 4 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 8, 1999, 5:21 PM CDT (22:21 UTC)
Expired
Apr 8, 1999, 6:25 PM CDT
In force
64 min
Issued by
NWS St. Louis, MO
Area
Whole counties

Counties Knox County, MO, Shelby County, MO

The radar

The St Louis radar (KLSX), 187 km from the middle of the area, began a volume at 22:22 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

TimeReportWhereRemark
Apr 8, 5:30 PM CDTHail 1.75Novelty, MO
Apr 8, 5:33 PM CDTHail 1Novelty, MO
Apr 8, 5:35 PM CDTTornado F2Novelty, MO
Apr 8, 5:38 PM CDTHail 1.75Novelty, 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.

IssuedProductOfficeLasted
Apr 8, 5:15 PM CDTTornado WatchSPC4 hr
Apr 8, 5:15 PM CDTTornado WatchSPC4 hr

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 10.4 hours before the alert went out and 229 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 1999-04-08Temperature 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°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Davenport, at 12:00Z on 1999-04-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 6 square meters per square second.1939587897117Sfc1 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
2467 m above ground
0-6 km bulk shear
61 kt
0-1 km storm-relative helicity
6 m²/s²
0-3 km storm-relative helicity
115 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.

999 
WFUS1 KSTL 082222 RRA
TORSTL
MOC103-205-082325-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
521 PM CDT THU APR 8 1999

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* TORNADO WARNING FOR...
  KNOX COUNTY IN NORTHEASTERN MISSOURI
  NORTHERN SHELBY COUNTY IN NORTHEASTERN MISSOURI

* UNTIL 625 PM CDT

* AT 520 PM CDT... NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  A TORNADO 8 MILES NORTH OF MACON... MOVING NORTHEAST AT 45 MPH.

* LOCATIONS IN THE PATH...
  NOVELTY
  LEONARD
  NEWARK
  KNOX CITY
  SHELBYVILLE

THIS STORM HAS A HISTORY OF PRODUCING TORNADOES AND LARGE HAIL

THIS IS A DANGEROUS SITUATION IF IN THE PATH...TAKE COVER NOW
MOVE TO A BASEMENT IF AVAILABLE. IF NOT...STAY ON THE LOWEST LEVEL
AND GO TO A SMALL INTERIOR ROOM. MOBILE HOMES AND AUTOMOBILESHOULD
BE ABANDONED IN FAVOR OF A STRONG STRUCTURE. AS A LAST RESORT...
MOVE TO A DITCH OR CULVERT AND COVER YOUR HEAD.

TPS/JP

What forecasters said that day

The local office's own words before this tornado 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 8, 11:55 AM CDT, 5 hours 26 minutes before
ILZ058>060-064-065-069-070-074-079-095>102-MOZ009-010-018-019-026-
027-034>036-041-042-047>052-059>065-072>075-084-085-099-091100-

SEVERE WEATHER OUTLOOK
NATIONAL WEATHER SERVICE ST LOUIS MO
1155 AM CDT THU APR 8 1999

...HIGH RISK OF SEVERE THUNDERSTORMS FOR EASTERN MISSOURI AND
SOUTHWEST ILLINOIS...

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.

A HIGH RISK OF SEVERE THUNDERSTORMS EXISTS FOR ALL OF EASTERN
MISSOURI AND SOUTHWEST ILLINOIS.  SKYWARN ACTIVATION WILL LIKELY
BE NEEDED THIS AFTERNOON AND THIS EVENING.

A WARM FRONT EXTENDED ACROSS CENTRAL MISSOURI LATE THIS MORNING.
SCATTERED SHOWERS AND THUNDERSTORMS HAVE DEVELOPED OVER EASTERN
MISSOURI AND SOUTHWEST ILLINOIS. THESE THUNDERSTORMS HAVE REMAINED
BELOW SEVERE LIMITS THIS MORNING.

THE WARM FRONT WILL MOVE THROUGH ALL BUT NORTHEAST MISSOURI AND
WEST-CENTRAL THIS AFTERNOON...AND WILL MOVE NORTH OF THESE AREAS
BY EARLY THIS EVENING. TO THE SOUTH OF THE WARM FRONT...STRONG SOUTH
WINDS WILL BRING VERY WARM...HUMID...AND UNSTABLE AIR OVER MOST OF
EASTERN MISSOURI AND SOUTHWESTERN ILLINOIS. ATMOSPHERIC CONDITIONS
WILL THEN BECOME IDEAL FOR THUNDERSTORM DEVELOPMENT.

A COLD FRONT WILL ENTER WESTERN MISSOURI EARLY THIS AFTERNOON AND
PUSH EASTWARD INTO CENTRAL MISSOURI BY EARLY THIS EVENING...AND
THROUGH EASTERN MISSOURI BY 1000 PM.  THUNDERSTORMS ARE EXPECTED
TO DEVELOP ALONG AND AHEAD OF THE FRONT. GIVEN THE UNSTABLE AIR AND
THE STRONG WINDS AT ALL LEVELS OF THE ATMOSPHERE...SOME OF THESE
STORMS ARE EXPECTED TO BECOME RAPIDLY SEVERE.

LOOK FOR THUNDERSTORM MOVEMENT TO BE TO THE EAST OR NORTHEAST AT 50
TO 60 MPH.  ALL THUNDERSTORMS WILL BE ACCOMPANIED BY DANGEROUS
LIGHTNING AND OCCASIONALLY HEAVY DOWNPOURS. IN ADDITION...SOME
THUNDERSTORMS WILL CONTAIN HAIL IN EXCESS OF THREE QUARTERS OF AN
INCH IN DIAMETER...WIND GUSTS GREATER THAN 55 MPH...AND POSSIBLY
TORNADOES.

AGAIN...A HIGH RISK OF SEVERE THUNDERSTORMS EXISTS FOR THE REGION.
SKYWARN ACTIVATION WILL LIKELY BE NEEDED THIS AFTERNOON AND THIS
EVENING.

BRITT/TES
Special weather statement, Apr 8, 11:55 AM CDT, 5 hours 26 minutes before
ILZ058>060-064-065-069-070-074-079-095>102-MOZ009-010-018-019-026-
027-034>036-041-042-047>052-059>065-072>075-084-085-099-091100-

SEVERE WEATHER OUTLOOK
NATIONAL WEATHER SERVICE ST LOUIS MO
1155 AM CDT THU APR 8 1999

...HIGH RISK OF SEVERE THUNDERSTORMS FOR EASTERN MISSOURI AND
SOUTHWEST ILLINOIS...

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.

A HIGH RISK OF SEVERE THUNDERSTORMS EXISTS FOR ALL OF EASTERN
MISSOURI AND SOUTHWEST ILLINOIS.  SKYWARN ACTIVATION WILL LIKELY
BE NEEDED THIS AFTERNOON AND THIS EVENING.

A WARM FRONT EXTENDED ACROSS CENTRAL MISSOURI LATE THIS MORNING.
SCATTERED SHOWERS AND THUNDERSTORMS HAVE DEVELOPED OVER EASTERN
MISSOURI AND SOUTHWEST ILLINOIS. THESE THUNDERSTORMS HAVE REMAINED
BELOW SEVERE LIMITS THIS MORNING.

THE WARM FRONT WILL MOVE THROUGH ALL BUT NORTHEAST MISSOURI AND
WEST-CENTRAL THIS AFTERNOON...AND WILL MOVE NORTH OF THESE AREAS
BY EARLY THIS EVENING. TO THE SOUTH OF THE WARM FRONT...STRONG SOUTH
WINDS WILL BRING VERY WARM...HUMID...AND UNSTABLE AIR OVER MOST OF
EASTERN MISSOURI AND SOUTHWESTERN ILLINOIS. ATMOSPHERIC CONDITIONS
WILL THEN BECOME IDEAL FOR THUNDERSTORM DEVELOPMENT.

A COLD FRONT WILL ENTER WESTERN MISSOURI EARLY THIS AFTERNOON AND
PUSH EASTWARD INTO CENTRAL MISSOURI BY EARLY THIS EVENING...AND
THROUGH EASTERN MISSOURI BY 1000 PM.  THUNDERSTORMS ARE EXPECTED
TO DEVELOP ALONG AND AHEAD OF THE FRONT. GIVEN THE UNSTABLE AIR AND
THE STRONG WINDS AT ALL LEVELS OF THE ATMOSPHERE...SOME OF THESE
STORMS ARE EXPECTED TO BECOME RAPIDLY SEVERE.

LOOK FOR THUNDERSTORM MOVEMENT TO BE TO THE EAST OR NORTHEAST AT 50
TO 60 MPH.  ALL THUNDERSTORMS WILL BE ACCOMPANIED BY DANGEROUS
LIGHTNING AND OCCASIONALLY HEAVY DOWNPOURS. IN ADDITION...SOME
THUNDERSTORMS WILL CONTAIN HAIL IN EXCESS OF THREE QUARTERS OF AN
INCH IN DIAMETER...WIND GUSTS GREATER THAN 55 MPH...AND POSSIBLY
TORNADOES.

AGAIN...A HIGH RISK OF SEVERE THUNDERSTORMS EXISTS FOR THE REGION.
SKYWARN ACTIVATION WILL LIKELY BE NEEDED THIS AFTERNOON AND THIS
EVENING.

BRITT/TES

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 8, 5:46 PM CDTSevere Thunderstorm WarningLSXBoone59 min
Apr 8, 5:50 PM CDTTornado WarningLSXLewis50 min
Apr 8, 5:54 PM CDTTornado WarningLSXBoone51 min
Apr 8, 6:09 PM CDTTornado WarningLSXClark46 min
Apr 8, 6:15 PM CDTTornado WarningLSXCole50 min
Apr 8, 6:21 PM CDTTornado WarningLSXAudrain49 min
Apr 8, 6:34 PM CDTTornado WarningLSXShelby46 min
Apr 8, 6:40 PM CDTTornado WarningLSXLewis50 min
Apr 8, 6:48 PM CDTTornado WarningLSXOsage47 min
Apr 8, 6:52 PM CDTTornado WarningLSXPike, Ralls48 min

Nearby

Tornado Warnings in Missouri, 1999Every tornado warning in 1999Tornadoes in 1999

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.