Alert archive / Missouri / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 188, NWS St. Louis, MO

December 10, 20214 counties in Missouri

NWS St. Louis, MO issued this severe thunderstorm warning at Dec 10, 2021, 8:29 PM CST for 4 counties in Missouri. It was in force for 30 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
Dec 10, 2021, 8:29 PM CST (02:29 UTC)
Expired
Dec 10, 2021, 8:59 PM CST
In force
30 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Tornado
Possible
Hail
0.75 in
Wind
60.0 mph

Counties City of Saint Louis, MO, Franklin County, MO, Jefferson County, MO, Saint Louis County, MO

The radar

The St Louis radar (KLSX), 29 km from the middle of the area, began a volume at 02:33 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.

IssuedProductOfficeLasted
Dec 10, 3:07 PM CSTTornado WatchSPC11 hr
Dec 10, 5:17 PM CSTTornado WatchSPC6 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 2.5 hours before the alert went out and 246 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, Lincoln, IL at 00:00Z on 2021-12-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 119 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, Lincoln, IL at 00:00Z on 2021-12-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 341 square meters per square second.1939587897Sfc1 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
119 J/kg
Mixed-layer CIN
-33 J/kg
Mixed-layer LCL
662 m above ground
0-6 km bulk shear
73 kt
0-1 km storm-relative helicity
341 m²/s²
0-3 km storm-relative helicity
357 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted.

763 
WUUS53 KLSX 110229
SVRLSX
MOC071-099-189-510-110315-
/O.NEW.KLSX.SV.W.0188.211211T0229Z-211211T0315Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service St Louis MO
829 PM CST Fri Dec 10 2021

The National Weather Service in St Louis has issued a

* Severe Thunderstorm Warning for...
  Western St. Louis City in east central Missouri...
  Northern Jefferson County in east central Missouri...
  East central Franklin County in east central Missouri...
  St. Louis County in east central Missouri...

* Until 915 PM CST.

* At 828 PM CST, severe thunderstorms were located along a line
  extending from Wildwood to near Pacific, moving northeast at 60
  mph.

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

  SOURCE...Radar indicated.

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

* Severe thunderstorms will be near...
  Ballwin, Manchester, Ellisville, Clarkson Valley and Winchester 
  around 835 PM CST.
  Chesterfield, Town and Country, Des Peres, Frontenac, Murphy, 
  Crystal Lake Park, Westwood and Country Life Acres around 840 PM 
  CST.
  University City, Kirkwood, Maryland Heights, Arnold, Creve Coeur, 
  Overland, St. Ann, Ladue, Sunset Hills and Olivette around 845 PM 
  CST.

Other locations in the path of these severe thunderstorms include
Webster Groves, Ferguson, Jennings, Crestwood, Berkeley, Richmond
Heights, Brentwood, St. John, Shrewsbury, Glendale, Clayton,
Bellefontaine Neighbors, Maplewood, Dellwood, Riverview, Spanish
Lake, Pagedale, Moline Acres, Wellston, Castle Point and St. Louis.

This includes the following highways...
 Interstate 44 in Missouri between exits 257 and 277.
 Interstate 55 in Missouri between exits 187 and 191.

This also includes Route 66 State Park, Castlewood State Park, and
Mastodon Historic Site.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 1100 PM CST for east central
Missouri. A Tornado Watch also remains in effect until 1100 PM CST
for east central Missouri.

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.

For your protection move to an interior room on the lowest floor of a
building.

A Tornado Watch remains in effect until 1100 PM CST for east central
Missouri. A Tornado Watch also remains in effect until 1100 PM CST
for east central Missouri.

&&

LAT...LON 3835 9037 3835 9077 3860 9075 3878 9020
TIME...MOT...LOC 0228Z 238DEG 53KT 3859 9066 3843 9069 

TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Britt
2 follow-up statements
131 
WWUS53 KLSX 110242
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
842 PM CST Fri Dec 10 2021

MOC071-110252-
/O.CAN.KLSX.SV.W.0188.000000T0000Z-211211T0315Z/
Franklin MO-
842 PM CST Fri Dec 10 2021

...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL FRANKLIN COUNTY
IS CANCELLED...

The storms which prompted the warning have moved out of the warned 
area. Therefore, the warning has been cancelled.

A Tornado Watch remains in effect until 1100 PM CST for east central
Missouri. A Tornado Watch also remains in effect until 1100 PM CST
for east central Missouri.

LAT...LON 3840 9035 3844 9060 3865 9061 3878 9020
TIME...MOT...LOC 0242Z 239DEG 49KT 3865 9050 3850 9049 

$$

MOC099-189-510-110315-
/O.CON.KLSX.SV.W.0188.000000T0000Z-211211T0315Z/
St. Louis City MO-Jefferson MO-St. Louis MO-
842 PM CST Fri Dec 10 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 915 PM CST
FOR NORTHEASTERN JEFFERSON AND CENTRAL ST. LOUIS COUNTIES AND WESTERN
ST. LOUIS CITY...

At 842 PM CST, severe thunderstorms were located along a line
extending from near Town and Country to Murphy, moving northeast at
55 mph.

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

SOURCE...Radar indicated.

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

These severe storms will be near...
  Maryland Heights, Ladue, Des Peres, Frontenac, Crystal Lake Park, 
  Huntleigh, Westwood and Country Life Acres around 845 PM CST.

Other locations in the path of these severe thunderstorms include
University City, Kirkwood, Creve Coeur, Overland, Clayton, St. Ann,
Crestwood, Sunset Hills, Olivette, St. John, Webster Groves,
Ferguson, Jennings, Berkeley, Richmond Heights, Brentwood, Maplewood,
Shrewsbury, Dellwood, Normandy, Bellefontaine Neighbors, Riverview,
Spanish Lake, Moline Acres, Castle Point, Glasgow Village and St.
Louis.

This also includes Route 66 State Park and Castlewood State Park.
 
This includes the following highways...
 Interstate 44 in Missouri between exits 266 and 277.
 Interstate 55 in Missouri between exits 190 and 191.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Tornado Watch remains in effect until 1100 PM CST for east central
Missouri. A Tornado Watch also remains in effect until 1100 PM CST
for east central Missouri.

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.

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 3840 9035 3844 9060 3865 9061 3878 9020
TIME...MOT...LOC 0242Z 239DEG 49KT 3865 9050 3850 9049 

TORNADO...POSSIBLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Britt
931 
WWUS53 KLSX 110259
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
859 PM CST Fri Dec 10 2021

MOC099-189-510-110308-
/O.CAN.KLSX.SV.W.0188.000000T0000Z-211211T0315Z/
St. Louis City MO-Jefferson MO-St. Louis MO-
859 PM CST Fri Dec 10 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN JEFFERSON AND
CENTRAL ST. LOUIS COUNTIES AND WESTERN ST. LOUIS CITY IS CANCELLED...
            
The storms which prompted the warning have weakened below severe
limits, and no longer pose an immediate threat to life or property.
Therefore, the warning has been cancelled.

A Tornado Watch remains in effect until 1100 PM CST for east central
Missouri. A Tornado Watch also remains in effect until 1100 PM CST
for east central Missouri.

LAT...LON 3840 9035 3844 9060 3865 9061 3878 9020
TIME...MOT...LOC 0257Z 238DEG 53KT 3877 9025 3862 9024 

$$

Britt

The office that day

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

IssuedProductOfficeCountiesLasted
Dec 10, 6:13 PM CSTSevere Thunderstorm WarningLSXBoone, Callaway, Cole, Moniteau47 min
Dec 10, 6:18 PM CSTSevere Thunderstorm WarningLSXCole, Osage42 min
Dec 10, 6:27 PM CSTTornado WarningLSXAudrain, Callaway34 min
Dec 10, 6:30 PM CSTTornado WarningLSXCallaway, Cole, Gasconade, Montgomery, Osage45 min
Dec 10, 6:42 PM CSTSevere Thunderstorm WarningLSXCrawford, Franklin, Gasconade, Osage48 min
Dec 10, 6:42 PM CSTTornado WarningLSXPike48 min
Dec 10, 6:49 PM CSTTornado WarningLSXFranklin, Gasconade, Osage, Warren41 min
Dec 10, 6:50 PM CSTTornado WarningLSXAudrain, Callaway, Montgomery, Pike, Ralls40 min
Dec 10, 7:00 PM CSTTornado WarningLSXGasconade, Lincoln, Montgomery, Pike, Warren45 min
Dec 10, 7:02 PM CSTTornado WarningLSXCrawford, Franklin, Gasconade43 min
Dec 10, 7:11 PM CSTTornado WarningLSXLincoln, Montgomery, Pike49 min
Dec 10, 7:16 PM CSTTornado WarningLSXFranklin, Lincoln, Saint Charles, Warren44 min
Dec 10, 7:30 PM CSTTornado WarningLSXLincoln45 min
Dec 10, 7:35 PM CSTTornado Warning Tornado observedLSXFranklin, Jefferson, Lincoln, Saint Charles, Saint Louis, Warren40 min
Dec 10, 7:49 PM CSTSevere Thunderstorm WarningLSXCrawford, Washington26 min
Dec 10, 8:06 PM CSTTornado Warning Tornado observedLSXSaint Charles, Saint Louis, City of Saint Louis39 min
Dec 10, 8:10 PM CSTSevere Thunderstorm WarningLSXFranklin35 min
Dec 10, 8:34 PM CSTSevere Thunderstorm WarningLSXCrawford, Franklin, Gasconade, Osage41 min
Dec 10, 8:47 PM CSTTornado WarningLSXFranklin, Gasconade, Warren43 min
Dec 10, 9:07 PM CSTSevere Thunderstorm WarningLSXFranklin, Jefferson, Lincoln, Saint Charles, Saint Louis, Warren and 1 more38 min
Dec 10, 9:39 PM CSTTornado WarningLSXSaint Charles, Saint Louis51 min
Dec 10, 10:00 PM CSTSevere Thunderstorm WarningLSXIron, Reynolds45 min
Dec 10, 10:05 PM CSTSevere Thunderstorm WarningLSXCity of Saint Louis25 min
Dec 10, 10:14 PM CSTTornado WarningLSXIron, Madison, Reynolds46 min
Dec 10, 10:19 PM CSTSevere Thunderstorm WarningLSXJefferson, Sainte Genevieve, Saint Francois41 min
Dec 10, 10:26 PM CSTSevere Thunderstorm WarningLSXReynolds20 min
Dec 10, 10:55 PM CSTSevere Thunderstorm WarningLSXMadison18 min

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.