Alert archive / Missouri / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 2, NWS St. Louis, MO
NWS St. Louis, MO issued this severe thunderstorm warning at Mar 11, 2021, 1:58 PM CST for 4 counties in Missouri. It was in force for 47 min. 1 report 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
- Mar 11, 2021, 1:58 PM CST (19:58 UTC)
- Expired
- Mar 11, 2021, 2:45 PM CST
- In force
- 47 min
- Issued by
- NWS St. Louis, MO
- Area
- Storm-based polygon
- Tornado
- Possible
- Hail
- 1.0 in
- Wind
- 60.0 mph
Counties Iron County, MO, Madison County, MO, Saint Francois County, MO, Sainte Genevieve County, MO
The radar
The St Louis radar (KLSX), 121 km from the middle of the area, began a volume at 20:02 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 |
|---|---|---|---|
| Mar 11, 2:25 PM CST | TSTM WND DMG | 1 S Fredericktown, MO | SPOTTER REPORTS SEVERAL TREES UP TO 10 TO 12 INCHES IN DIAMETER SNAPPED AND SPLIT IN SOUTH FREDERICKTOWN, WITH AT LEAST ONE FALLING AGAINST A HOUSE. A ROOF WAS TORN OFF OF A METAL GARAGE ALSO. TIME ESTIMATED FROM RADAR. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Springfield, MO (KSGF), launched 12:00Z, 8.0 hours before the alert went out and 304 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.
- Mixed-layer CAPE
- 286 J/kg
- Mixed-layer CIN
- -25 J/kg
- Mixed-layer LCL
- 652 m above ground
- 0-6 km bulk shear
- 51 kt
- 0-1 km storm-relative helicity
- 237 m²/s²
- 0-3 km storm-relative helicity
- 303 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 3.1
The text
As transmitted.
686
WUUS53 KLSX 111958
SVRLSX
MOC093-123-186-187-112045-
/O.NEW.KLSX.SV.W.0002.210311T1958Z-210311T2045Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service St Louis MO
158 PM CST Thu Mar 11 2021
The National Weather Service in St Louis has issued a
* Severe Thunderstorm Warning for...
Northeastern Iron County in southeastern Missouri...
Southeastern Ste. Genevieve County in southeastern Missouri...
Northern Madison County in southeastern Missouri...
Southern St. Francois County in southeastern Missouri...
* Until 245 PM CST.
* At 158 PM CST, a severe thunderstorm was located near Pilot Knob,
moving east at 45 mph.
HAZARD...60 mph wind gusts and quarter size hail.
SOURCE...Radar indicated.
IMPACT...Hail damage to vehicles is expected. Expect wind damage
to roofs, siding, and trees.
* Locations impacted include...
Fredericktown, Ironton, Pilot Knob, Iron Mountain Lake, Arcadia,
Junction City, Cobalt, Belleview, Womac, Knob Lick, Iron Mountain,
Roselle, Catherine Place, Granite, Mine La Motte, Libertyville and
Doe Run.
This also includes Fort Davidson Historic Site and Elephant Rocks
State Park.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 3754 9077 3760 9077 3760 9083 3773 9083
3777 9004 3767 9011 3764 9015 3751 9014
TIME...MOT...LOC 1958Z 269DEG 38KT 3764 9070
TORNADO...POSSIBLE
HAIL...1.00IN
WIND...60MPH
$$
Carney2 follow-up statements
624
WWUS53 KLSX 112018
SVSLSX
Severe Weather Statement
National Weather Service St Louis MO
218 PM CST Thu Mar 11 2021
MOC093-112027-
/O.CAN.KLSX.SV.W.0002.000000T0000Z-210311T2045Z/
Iron MO-
218 PM CST Thu Mar 11 2021
...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN IRON COUNTY IS
CANCELLED...
The severe thunderstorm which prompted the warning has moved out of
the warned area. Therefore, the warning has been cancelled.
LAT...LON 3753 9055 3760 9055 3760 9053 3764 9053
3774 9055 3777 9004 3767 9011 3764 9015
3751 9014
TIME...MOT...LOC 2017Z 271DEG 44KT 3763 9039
$$
MOC123-186-187-112045-
/O.CON.KLSX.SV.W.0002.000000T0000Z-210311T2045Z/
Ste. Genevieve MO-Madison MO-St. Francois MO-
218 PM CST Thu Mar 11 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 245 PM CST
FOR SOUTHEASTERN STE. GENEVIEVE...NORTHERN MADISON AND SOUTHERN ST.
FRANCOIS COUNTIES IN SOUTHEASTERN MISSOURI...
At 217 PM CST, a severe thunderstorm was located near Knob Lick,
moving east at 50 mph.
HAZARD...60 mph wind gusts and quarter size hail.
SOURCE...Radar indicated.
IMPACT...Hail damage to vehicles is expected. Expect wind damage to
roofs, siding, and trees.
Locations impacted include...
Fredericktown, Junction City, Cobalt, Womac, Roselle, Knob Lick, Mine
La Motte, Libertyville, Catherine Place and Doe Run.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 3753 9055 3760 9055 3760 9053 3764 9053
3774 9055 3777 9004 3767 9011 3764 9015
3751 9014
TIME...MOT...LOC 2017Z 271DEG 44KT 3763 9039
TORNADO...POSSIBLE
HAIL...1.00IN
WIND...60MPH
$$
Carney714
WWUS53 KLSX 112043
SVSLSX
Severe Weather Statement
National Weather Service St Louis MO
243 PM CST Thu Mar 11 2021
MOC123-186-187-112053-
/O.EXP.KLSX.SV.W.0002.000000T0000Z-210311T2045Z/
Ste. Genevieve MO-Madison MO-St. Francois MO-
243 PM CST Thu Mar 11 2021
...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN STE. GENEVIEVE...
NORTHERN MADISON AND SOUTHERN ST. FRANCOIS COUNTIES IN SOUTHEASTERN
MISSOURI WILL EXPIRE AT 245 PM CST...
The storm which prompted the warning has moved out of the area.
Therefore, the warning will be allowed to expire.
LAT...LON 3753 9055 3760 9055 3760 9053 3764 9053
3774 9055 3777 9004 3767 9011 3764 9015
3751 9014
TIME...MOT...LOC 2043Z 269DEG 38KT 3763 9005
$$
CarneyThe office that day
Everything else NWS St. Louis, MO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 11, 3:27 AM CST | Flood Watch | LSX | Boone, Callaway, Cole, Crawford, Franklin, Gasconade and 14 more | 55 hr |
| Mar 11, 12:43 PM CST | Severe Thunderstorm Warning | LSX | Iron, Madison, Sainte Genevieve, Saint Francois | 22 min |
| Mar 11, 3:38 PM CST | Areal Flood Advisory | LSX | Crawford, Iron, Sainte Genevieve, Saint Francois, Washington | 3 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.