Alert archive / Missouri / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 68, NWS St. Louis, MO

April 21, 1999Audrain County, Missouri

NWS St. Louis, MO issued this severe thunderstorm warning at Apr 21, 1999, 2:28 AM CDT for Audrain County, Missouri. It was in force for 32 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 21, 1999, 2:28 AM CDT (07:28 UTC)
Expired
Apr 21, 1999, 3:00 AM CDT
In force
32 min
Issued by
NWS St. Louis, MO
Area
Whole counties

County Audrain County, MO

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 7.5 hours before the alert went out and 290 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 00:00Z on 1999-04-21Temperature 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 00:00Z on 1999-04-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 215 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
986 m above ground
0-6 km bulk shear
53 kt
0-1 km storm-relative helicity
215 m²/s²
0-3 km storm-relative helicity
513 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 
WUUS1 KSTL 210729 RRA
SVRSTL
MOC007-210800-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
228 AM CDT WED APR 21 1999

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

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

* UNTIL 300 AM CDT

* AT 227 AM...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 15 MILES NORTHWEST OF MEXICO... MOVING EAST
  AT 30 MPH.

* LOCATIONS THAT WILL BE AFFECTED...
  MEXICO
  LADDONIA

THE PRIMARY SEVERE WEATHER THREAT IS DAMAGING HAIL. LARGE HAIL CAN
CAUSE EXTENSIVE PROPERTY DAMAGE AN SERIOUS INJURY TO PEOPLE CAUGHT
OUTDOORS. MOVE INSIDE A STURDY BUILDING IMMEDIATELY.

BRITT/TRUETT

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 20, 9:56 PM CDTSevere Thunderstorm WarningLSXAudrain49 min
Apr 20, 10:45 PM CDTSevere Thunderstorm WarningLSXLewis, Marion35 min
Apr 20, 10:51 PM CDTSevere Thunderstorm WarningLSXAudrain, Monroe49 min
Apr 20, 11:13 PM CDTSevere Thunderstorm WarningLSXPike47 min
Apr 20, 11:56 PM CDTSevere Thunderstorm WarningLSXPike49 min
Apr 21, 1:36 AM CDTSevere Thunderstorm WarningLSXAudrain49 min
Apr 21, 2:36 AM CDTSevere Thunderstorm WarningLSXSaint Charles, Warren49 min

Nearby

Severe Thunderstorm Warnings in Missouri, 1999Every 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.