Alert archive / Missouri / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 22, NWS St. Louis, MO

February 11, 1999Boone County, Missouri

NWS St. Louis, MO issued this severe thunderstorm warning at Feb 11, 1999, 12:04 PM CST for Boone County, Missouri. It was in force for 51 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: Feb 11, 1999, 12:04 PM CST (18:04 UTC)
Expired: Feb 11, 1999, 12:55 PM CST
In force: 51 min
Issued by: NWS St. Louis, MO
Area: Whole counties

County Boone County, MO

The radar

The St Louis radar (KLSX), 145 km from the middle of the area, began a volume at 18:04 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
Feb 11, 11:15 AM CST	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Springfield, MO (KSGF), launched 12:00Z, 6.1 hours before the alert went out and 267 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: 261 J/kg
Mixed-layer CIN: -163 J/kg
Mixed-layer LCL: 871 m above ground
0-6 km bulk shear: 30 kt
0-1 km storm-relative helicity: 275 m²/s²
0-3 km storm-relative helicity: 308 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 0.4

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KSTL 111803
SVRSTL
MOC019-111855-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
1204 PM CST THU FEB 11 1999

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  BOONE COUNTY IN CENTRAL MISSOURI

* UNTIL 1255 PM CST

* AT 1203 PM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  LINE OF SEVERE THUNDERSTORMS ACROSS EASTERN COOPER COUNTY...
  MOVING NORTHEAST AT 45 MPH.

* LOCATIONS THAT WILL BE AFFECTED...
  COLUMBIA
  HUNTSDALE



THE PRIMARY SEVERE WEATHER THREAT IS DAMAGING WINDS. MOVE QUICKLY
TO A STURDY BUILDING AND STAY AWAY FROM DOORS AND WINDOWS.



GKS/RP

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, Feb 11, 10:25 AM CST, 1 hour 39 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>075-084-085-099-112300-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
1025 AM CST THU FEB 11 1999

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 SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
THROUGH EARLY THIS EVENING ACROSS THE ENTIRE REGION.  THIS INCLUDES
THE LARGER CITIES OF ST LOUIS...COLUMBIA...JEFFERSON CITY...
HANNIBAL...FARMINGTON...STE GENEVIEVE...QUINCY IL...VANDALIA IL...AND
CENTRALIA IL.

A LINE OF STRONG TO SEVERE THUNDERSTORMS IS EXPECTED TO PUSH
WEST TO EAST ACROSS THE AREA.  THE MAIN SEVERE WEATHER THREAT
WITH THIS LINE OF STORMS WILL BE DAMAGING WIND GUSTS IN EXCESS
OF 60 MPH.  THE THREAT OVER CENTRAL MISSOURI SHOULD BE EARLY
THIS AFTERNOON...OVER EASTERN MISSOURI AROUND MIDDLE AFTERNOON...
AND OVER WESTERN ILLINOIS DURING THE LATE AFTERNOON AND EARLY
EVENING.

STORM SPOTTER GROUPS AND EMERGENCY MANAGERS SHOULD KEEP ADVISED OF
THE LATEST FORECASTS...AND MONITOR WEATHER INFORMATION FOR POSSIhBLE
SKYWARN ACTION.

GLASS

The office that day

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

Issued	Product	Office	Counties	Lasted
Feb 11, 11:10 AM CST	Severe Thunderstorm Warning	LSX	Knox, Scotland	50 min
Feb 11, 11:28 AM CST	Severe Thunderstorm Warning	LSX	Clark	47 min
Feb 11, 11:31 AM CST	Severe Thunderstorm Warning	LSX	Monroe, Shelby	64 min
Feb 11, 11:54 AM CST	Severe Thunderstorm Warning	LSX	Lewis	46 min
Feb 11, 12:02 PM CST	Severe Thunderstorm Warning	LSX	Marion	48 min
Feb 11, 12:25 PM CST	Severe Thunderstorm Warning	LSX	Audrain, Callaway	50 min
Feb 11, 12:46 PM CST	Severe Thunderstorm Warning	LSX	Osage	49 min
Feb 11, 1:12 PM CST	Severe Thunderstorm Warning	LSX	Gasconade	48 min
Feb 11, 1:26 PM CST	Severe Thunderstorm Warning	LSX	Franklin	49 min
Feb 11, 1:35 PM CST	Severe Thunderstorm Warning	LSX	Franklin, Warren	50 min
Feb 11, 1:48 PM CST	Tornado Warning	LSX	Lincoln	47 min
Feb 11, 1:56 PM CST	Tornado Warning	LSX	Pike	49 min
Feb 11, 2:47 PM CST	Severe Thunderstorm Warning	LSX	Saint Louis, City of Saint Louis	48 min

Nearby

Severe Thunderstorm Warnings in Missouri, 1999 Every severe thunderstorm warning 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.