Alert archive / Missouri / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 189, NWS St. Louis, MO

December 10, 20214 counties in Missouri

NWS St. Louis, MO issued this severe thunderstorm warning at Dec 10, 2021, 8:34 PM CST for 4 counties in Missouri. It was in force for 41 min. 4 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Dec 10, 2021, 8:34 PM CST (02:34 UTC)
Expired: Dec 10, 2021, 9:15 PM CST
In force: 41 min
Issued by: NWS St. Louis, MO
Area: Storm-based polygon
Tornado: Possible
Hail: 0.75 in
Wind: 60.0 mph

Counties Crawford County, MO, Franklin County, MO, Gasconade County, MO, Osage County, MO

The radar

The St Louis radar (KLSX), 70 km from the middle of the area, began a volume at 02:38 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

Time	Report	Where	Remark
Dec 10, 9:09 PM CST	TSTM WND DMG	5 Sw Union, MO	FRANKLIN COUNTY DISPATCH REPORTED TREES AND POWER LINES WERE DOWN ALONG CAMP MO-VAL ROAD WSW OF UNION. TIME ESTIMATED FROM RADAR.
Dec 10, 9:09 PM CST	TSTM WND DMG	Gerald, MO	FRANKLIN COUNTY DISPATCH REPORTED PHONE LINES DOWN IN GERALD ACROSS WEST 6TH STREET. TIME ESTIMATED FROM RADAR.
Dec 10, 9:13 PM CST	TSTM WND DMG	2 Ssw Union, MO	FRANKLIN COUNTY DISPATCH REPORTED TREES DOWN ACROSS NORTH BEND LOOP SW OF UNION. TIME ESTIMATED FROM RADAR.
Dec 10, 9:14 PM CST	HAIL 0.25	3 W Union, MO	REPORT OF PEA SIZED HAIL JUST WEST OF UNION, MO.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Dec 10, 3:07 PM CST	Tornado Watch	SPC	11 hr
Dec 10, 5:17 PM CST	Tornado Watch	SPC	6 hr

The nearest sounding before it

Springfield, MO (KSGF), launched 00:00Z, 2.6 hours before the alert went out and 270 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: 637 J/kg
Mixed-layer CIN: -23 J/kg
Mixed-layer LCL: 1113 m above ground
0-6 km bulk shear: 80 kt
0-1 km storm-relative helicity: 344 m²/s²
0-3 km storm-relative helicity: 300 m²/s²
Significant tornado parameter: 1.2
Supercell composite: 8.4

Open this sounding in Storm Lab

The text

As transmitted.

295 
WUUS53 KLSX 110234
SVRLSX
MOC055-071-073-151-110315-
/O.NEW.KLSX.SV.W.0189.211211T0234Z-211211T0315Z/

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

The National Weather Service in St Louis has issued a

* Severe Thunderstorm Warning for...
  Northwestern Crawford County in east central Missouri...
  Western Franklin County in east central Missouri...
  Southeastern Osage County in central Missouri...
  Gasconade County in east central Missouri...

* Until 915 PM CST.

* At 833 PM CST, severe thunderstorms were located along a line
  extending from 7 miles east of Rich Fountain to Belle to 10 miles
  southeast of Vienna, 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...
  Bland around 840 PM CST.
  Mount Sterling around 845 PM CST.
  Owensville and Drake around 850 PM CST.

Other locations in the path of these severe thunderstorms include
Rosebud, Swiss, Gerald, New Haven, Washington and Beaufort.

This includes Interstate 44 in Missouri between exits 225 and 230.
 
This also includes Meramec State Park.
 
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 central and 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 central and east central Missouri.

&&

LAT...LON 3840 9182 3870 9137 3871 9131 3865 9123
      3862 9123 3860 9113 3861 9107 3854 9096
      3821 9110 3809 9152 3815 9153 3815 9164
      3829 9165 3829 9182
TIME...MOT...LOC 0233Z 237DEG 51KT 3838 9174 3827 9174 3810 9179 

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

278 
WWUS53 KLSX 110253
SVSLSX

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

MOC151-110302-
/O.CAN.KLSX.SV.W.0189.000000T0000Z-211211T0315Z/
Osage MO-
853 PM CST Fri Dec 10 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN OSAGE 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 3870 9137 3871 9131 3865 9123 3862 9123
      3860 9113 3861 9107 3854 9096 3821 9110
      3809 9152 3815 9153 3833 9153 3845 9152
      3859 9154
TIME...MOT...LOC 0252Z 235DEG 72KT 3860 9138 3849 9133 3832 9144 

$$

MOC055-071-073-110315-
/O.CON.KLSX.SV.W.0189.000000T0000Z-211211T0315Z/
Crawford MO-Franklin MO-Gasconade MO-
853 PM CST Fri Dec 10 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 915 PM CST
FOR NORTHWESTERN CRAWFORD...WESTERN FRANKLIN AND EASTERN GASCONADE
COUNTIES...

At 852 PM CST, severe thunderstorms were located along a line
extending from near Swiss to 6 miles north of Gerald to near
Owensville, moving northeast at 80 mph.

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

SOURCE...Radar indicated.

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

Locations impacted include...
  New Haven, Washington and Union.

This also includes Meramec State Park.
 
This includes Interstate 44 in Missouri between exits 225 and 230.
 
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 3870 9137 3871 9131 3865 9123 3862 9123
      3860 9113 3861 9107 3854 9096 3821 9110
      3809 9152 3815 9153 3833 9153 3845 9152
      3859 9154
TIME...MOT...LOC 0252Z 235DEG 72KT 3860 9138 3849 9133 3832 9144 

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

$$

Britt

932 
WWUS53 KLSX 110315
SVSLSX

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

MOC055-071-073-110324-
/O.EXP.KLSX.SV.W.0189.000000T0000Z-211211T0315Z/
Crawford MO-Franklin MO-Gasconade MO-
915 PM CST Fri Dec 10 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN CRAWFORD...
WESTERN FRANKLIN AND EASTERN GASCONADE COUNTIES WILL EXPIRE AT 915 PM
CST...
    
The storms which prompted the warning have moved out of the area.
Therefore, the warning will be allowed to expire.

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 3870 9137 3871 9131 3865 9123 3862 9123
      3860 9113 3861 9107 3854 9096 3821 9110
      3809 9152 3815 9153 3833 9153 3845 9152
      3859 9154
TIME...MOT...LOC 0314Z 237DEG 51KT 3877 9105 3866 9100 3849 9111 

$$

Britt

The office that day

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

Issued	Product	Office	Counties	Lasted
Dec 10, 6:13 PM CST	Severe Thunderstorm Warning	LSX	Boone, Callaway, Cole, Moniteau	47 min
Dec 10, 6:18 PM CST	Severe Thunderstorm Warning	LSX	Cole, Osage	42 min
Dec 10, 6:27 PM CST	Tornado Warning	LSX	Audrain, Callaway	34 min
Dec 10, 6:30 PM CST	Tornado Warning	LSX	Callaway, Cole, Gasconade, Montgomery, Osage	45 min
Dec 10, 6:42 PM CST	Severe Thunderstorm Warning	LSX	Crawford, Franklin, Gasconade, Osage	48 min
Dec 10, 6:42 PM CST	Tornado Warning	LSX	Pike	48 min
Dec 10, 6:49 PM CST	Tornado Warning	LSX	Franklin, Gasconade, Osage, Warren	41 min
Dec 10, 6:50 PM CST	Tornado Warning	LSX	Audrain, Callaway, Montgomery, Pike, Ralls	40 min
Dec 10, 7:00 PM CST	Tornado Warning	LSX	Gasconade, Lincoln, Montgomery, Pike, Warren	45 min
Dec 10, 7:02 PM CST	Tornado Warning	LSX	Crawford, Franklin, Gasconade	43 min
Dec 10, 7:11 PM CST	Tornado Warning	LSX	Lincoln, Montgomery, Pike	49 min
Dec 10, 7:16 PM CST	Tornado Warning	LSX	Franklin, Lincoln, Saint Charles, Warren	44 min
Dec 10, 7:30 PM CST	Tornado Warning	LSX	Lincoln	45 min
Dec 10, 7:35 PM CST	Tornado Warning Tornado observed	LSX	Franklin, Jefferson, Lincoln, Saint Charles, Saint Louis, Warren	40 min
Dec 10, 7:49 PM CST	Severe Thunderstorm Warning	LSX	Crawford, Washington	26 min
Dec 10, 8:06 PM CST	Tornado Warning Tornado observed	LSX	Saint Charles, Saint Louis, City of Saint Louis	39 min
Dec 10, 8:10 PM CST	Severe Thunderstorm Warning	LSX	Franklin	35 min
Dec 10, 8:29 PM CST	Severe Thunderstorm Warning	LSX	Franklin, Jefferson, Saint Louis, City of Saint Louis	30 min
Dec 10, 8:47 PM CST	Tornado Warning	LSX	Franklin, Gasconade, Warren	43 min
Dec 10, 9:07 PM CST	Severe Thunderstorm Warning	LSX	Franklin, Jefferson, Lincoln, Saint Charles, Saint Louis, Warren and 1 more	38 min
Dec 10, 9:39 PM CST	Tornado Warning	LSX	Saint Charles, Saint Louis	51 min
Dec 10, 10:00 PM CST	Severe Thunderstorm Warning	LSX	Iron, Reynolds	45 min
Dec 10, 10:05 PM CST	Severe Thunderstorm Warning	LSX	City of Saint Louis	25 min
Dec 10, 10:14 PM CST	Tornado Warning	LSX	Iron, Madison, Reynolds	46 min
Dec 10, 10:19 PM CST	Severe Thunderstorm Warning	LSX	Jefferson, Sainte Genevieve, Saint Francois	41 min
Dec 10, 10:26 PM CST	Severe Thunderstorm Warning	LSX	Reynolds	20 min
Dec 10, 10:55 PM CST	Severe Thunderstorm Warning	LSX	Madison	18 min

Nearby

Severe Thunderstorm Warnings in Missouri, 2021 Every 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.