Alert archive / Missouri / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 79, NWS St. Louis, MO

June 19, 2021Callaway County, Missouri

NWS St. Louis, MO issued this severe thunderstorm warning at Jun 19, 2021, 9:33 PM CDT for Callaway County, Missouri. It was in force for 42 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jun 19, 2021, 9:33 PM CDT (02:33 UTC)
Expired
Jun 19, 2021, 10:15 PM CDT
In force
42 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Tornado
Possible
Hail
0.88 in
Wind
60.0 mph

County Callaway County, MO

The radar

The St Louis radar (KLSX), 108 km from the middle of the area, began a volume at 02:36 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

Springfield, MO (KSGF), launched 00:00Z, 2.6 hours before the alert went out and 284 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, Springfield, MO at 00:00Z on 2021-06-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1685 joules per kilogram.LCLLFCEL10008507005003002001001 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, Springfield, MO at 00:00Z on 2021-06-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 37 square meters per square second.193958Sfc1 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
1685 J/kg
Mixed-layer CIN
-99 J/kg
Mixed-layer LCL
1459 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
37 m²/s²
0-3 km storm-relative helicity
116 m²/s²
Significant tornado parameter
0.1
Supercell composite
1.0

Open this sounding in Storm Lab

The text

As transmitted.

409 
WUUS53 KLSX 200233
SVRLSX
MOC027-200315-
/O.NEW.KLSX.SV.W.0079.210620T0233Z-210620T0315Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service St Louis MO
933 PM CDT Sat Jun 19 2021

The National Weather Service in St Louis has issued a

* Severe Thunderstorm Warning for...
  Northeastern Callaway County in central Missouri...

* Until 1015 PM CDT.

* At 932 PM CDT, a severe thunderstorm was located near Auxvasse,
  moving southeast at 25 mph.

  HAZARD...60 mph wind gusts and nickel size hail.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees.

* This severe thunderstorm will be near...
  Williamsburg around 950 PM CDT.

This includes Interstate 70 in Missouri between exits 144 and 161.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.

Intense thunderstorm lines can produce brief tornadoes and widespread
significant wind damage. Although a tornado is not immediately
likely, it is best to move to an interior room on the lowest floor of
a building. This storm may cause serious injury and significant
property damage.

&&

LAT...LON 3906 9201 3906 9193 3904 9163 3871 9165
      3884 9205
TIME...MOT...LOC 0232Z 297DEG 23KT 3894 9187 

TORNADO...POSSIBLE
HAIL...0.88IN
WIND...60MPH
 
$$

GKS
2 follow-up statements
501 
WWUS53 KLSX 200249
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
949 PM CDT Sat Jun 19 2021

MOC027-200315-
/O.CON.KLSX.SV.W.0079.000000T0000Z-210620T0315Z/
Callaway MO-
949 PM CDT Sat Jun 19 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1015 PM CDT
FOR NORTHEASTERN CALLAWAY COUNTY...

At 948 PM CDT, a severe thunderstorm was located near Williamsburg,
moving southeast at 25 mph.

HAZARD...60 mph wind gusts and nickel size hail.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

Locations impacted include...
  Williamsburg.

This includes Interstate 70 in Missouri between exits 155 and 161.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.

Intense thunderstorm lines can produce brief tornadoes and widespread
significant wind damage. Although a tornado is not immediately
likely, it is best to move to an interior room on the lowest floor of
a building. This storm may cause serious injury and significant
property damage.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3901 9189 3899 9164 3871 9165 3883 9200
TIME...MOT...LOC 0248Z 311DEG 18KT 3888 9182 

TORNADO...POSSIBLE
HAIL...0.88IN
WIND...60MPH
 
$$

GKS
149 
WWUS53 KLSX 200312
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
1012 PM CDT Sat Jun 19 2021

MOC027-200321-
/O.EXP.KLSX.SV.W.0079.000000T0000Z-210620T0315Z/
Callaway MO-
1012 PM CDT Sat Jun 19 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN CALLAWAY COUNTY
WILL EXPIRE AT 1015 PM CDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  However small
hail, gusty winds and heavy rain are still possible with this
thunderstorm.

LAT...LON 3901 9189 3899 9164 3871 9165 3883 9200
TIME...MOT...LOC 0311Z 297DEG 23KT 3882 9166 

$$

GKS

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 19, 7:12 PM CDTSevere Thunderstorm WarningLSXLincoln, Pike48 min
Jun 19, 7:31 PM CDTSevere Thunderstorm WarningLSXLincoln, Saint Charles44 min
Jun 19, 8:00 PM CDTSevere Thunderstorm WarningLSXFranklin, Saint Charles, Saint Louis21 min
Jun 19, 8:42 PM CDTFlash Flood WarningLSXAudrain, Boone, Monroe6 hr
Jun 19, 11:49 PM CDTAreal Flood WarningLSXMarion, Pike, Ralls11 hr
Jun 20, 1:39 AM CDTFlash Flood WarningLSXBoone5 hr
Jun 20, 2:13 AM CDTAreal Flood WarningLSXAudrain, Boone, Monroe3 hr

Nearby

Severe Thunderstorm Warnings in Missouri, 2021Every severe thunderstorm warning in 2021

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.