Alert archive / Missouri / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 83, NWS St. Louis, MO

June 20, 20214 counties in Missouri; Pike County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Jun 20, 2021, 9:59 PM CDT for 4 counties in Missouri; Pike County, Illinois. It was in force for 46 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
Jun 20, 2021, 9:59 PM CDT (02:59 UTC)
Expired
Jun 20, 2021, 10:45 PM CDT
In force
46 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Hail
1.0 in
Wind
70.0 mph

Counties Pike County, IL, Marion County, MO, Monroe County, MO, Pike County, MO, Ralls County, MO

The radar

The St Louis radar (KLSX), 109 km from the middle of the area, began a volume at 03:03 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

TimeReportWhereRemark
Jun 20, 10:10 PM CDTTSTM WND DMGPerry, MOSEVERAL LARGE TREE LIMBS WERE BLOWN DOWN AROUND TOWN.

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.

IssuedProductOfficeLasted
Jun 20, 8:10 PM CDTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 3.0 hours before the alert went out and 244 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 2021-06-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1058 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, Davenport, at 00:00Z on 2021-06-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 174 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
1058 J/kg
Mixed-layer CIN
-19 J/kg
Mixed-layer LCL
1009 m above ground
0-6 km bulk shear
52 kt
0-1 km storm-relative helicity
174 m²/s²
0-3 km storm-relative helicity
230 m²/s²
Significant tornado parameter
1.4
Supercell composite
7.8

Open this sounding in Storm Lab

The text

As transmitted.

736 
WUUS53 KLSX 210259
SVRLSX
ILC149-MOC127-137-163-173-210345-
/O.NEW.KLSX.SV.W.0083.210621T0259Z-210621T0345Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service St Louis MO
959 PM CDT Sun Jun 20 2021

The National Weather Service in St Louis has issued a

* Severe Thunderstorm Warning for...
  Southwestern Pike County in west central Illinois...
  Ralls County in northeastern Missouri...
  South central Marion County in northeastern Missouri...
  Eastern Monroe County in northeastern Missouri...
  Northwestern Pike County in northeastern Missouri...

* Until 1045 PM CDT.

* At 959 PM CDT, severe thunderstorms were located along a line
  extending from 8 miles southeast of Hannibal to near Perry, moving
  east at 60 mph.

  HAZARD...70 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect considerable 
           tree damage. Wind damage is also likely to mobile homes, 
           roofs, and outbuildings.

* Severe thunderstorms will be near...
  Spencerburg around 1015 PM CDT.

Other locations in the path of these severe thunderstorms include
Curryville, Bowling Green and Tarrants.

This also includes Mark Twain Lake Recreational Area.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3959 9093 3927 9118 3944 9210 3974 9166
TIME...MOT...LOC 0259Z 282DEG 50KT 3965 9124 3938 9170 

HAIL...1.00IN
WIND...70MPH
 
$$

19
2 follow-up statements
139 
WWUS53 KLSX 210316
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
1016 PM CDT Sun Jun 20 2021

MOC127-210326-
/O.CAN.KLSX.SV.W.0083.000000T0000Z-210621T0345Z/
Marion MO-
1016 PM CDT Sun Jun 20 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTH CENTRAL MARION COUNTY IS
CANCELLED...

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

A Severe Thunderstorm Watch remains in effect until 100 AM CDT for
west central Illinois...and northeastern Missouri.

LAT...LON 3959 9093 3927 9118 3942 9197 3969 9141
TIME...MOT...LOC 0316Z 270DEG 50KT 3961 9095 3934 9141 

$$

ILC149-MOC137-163-173-210345-
/O.CON.KLSX.SV.W.0083.000000T0000Z-210621T0345Z/
Pike IL-Ralls MO-Monroe MO-Pike MO-
1016 PM CDT Sun Jun 20 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1045 PM CDT
FOR SOUTHWESTERN PIKE COUNTY IN WEST CENTRAL ILLINOIS...RALLS...
SOUTHEASTERN MONROE AND NORTHWESTERN PIKE COUNTIES IN NORTHEASTERN
MISSOURI...

At 1016 PM CDT, severe thunderstorms were located along a line
extending from 6 miles north of Atlas to near Curryville, moving east
at 60 mph.

HAZARD...70 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect considerable 
         tree damage. Wind damage is also likely to mobile homes, 
         roofs, and outbuildings.

Locations impacted include...
  Tarrants.

This also includes Mark Twain Lake Recreational Area.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3959 9093 3927 9118 3942 9197 3969 9141
TIME...MOT...LOC 0316Z 270DEG 50KT 3961 9095 3934 9141 

HAIL...1.00IN
WIND...70MPH
 
$$

19
702 
WWUS53 KLSX 210329
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
1029 PM CDT Sun Jun 20 2021

MOC137-210339-
/O.CAN.KLSX.SV.W.0083.000000T0000Z-210621T0345Z/
Monroe MO-
1029 PM CDT Sun Jun 20 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN MONROE COUNTY IS
CANCELLED...

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

A Severe Thunderstorm Watch remains in effect until 100 AM CDT for
west central Illinois...and central and northeastern Missouri.

LAT...LON 3959 9093 3927 9118 3937 9172 3965 9122
TIME...MOT...LOC 0329Z 282DEG 50KT 3958 9074 3931 9120 

$$

ILC149-MOC163-173-210345-
/O.CON.KLSX.SV.W.0083.000000T0000Z-210621T0345Z/
Pike IL-Ralls MO-Pike MO-
1029 PM CDT Sun Jun 20 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1045 PM CDT
FOR SOUTHWESTERN PIKE COUNTY IN WEST CENTRAL ILLINOIS...SOUTHERN
RALLS AND NORTHWESTERN PIKE COUNTIES IN NORTHEASTERN MISSOURI...

At 1029 PM CDT, severe thunderstorms were located along a line
extending from near Pittsfield to near Bowling Green, moving east at
60 mph.

HAZARD...70 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect considerable 
         tree damage. Wind damage is also likely to mobile homes, 
         roofs, and outbuildings.

Locations impacted include...
Bowling Green, Louisiana, Frankford, Pike, Curryville, Tarrants,
Spencerburg, St. Clement, Rockport and Ashburn.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3959 9093 3927 9118 3937 9172 3965 9122
TIME...MOT...LOC 0329Z 282DEG 50KT 3958 9074 3931 9120 

HAIL...1.00IN
WIND...70MPH
 
$$

19

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 20, 8:41 PM CDTSevere Thunderstorm WarningLSXKnox, Lewis, Shelby49 min
Jun 20, 9:07 PM CDTTornado WarningLSXMarion, Shelby38 min
Jun 20, 9:17 PM CDTSevere Thunderstorm WarningLSXKnox, Lewis, Marion, Monroe, Ralls, Shelby43 min
Jun 20, 9:42 PM CDTSevere Thunderstorm WarningLSXAudrain, Boone, Monroe48 min
Jun 20, 10:10 PM CDTSevere Thunderstorm WarningLSXAudrain, Boone, Monroe, Montgomery, Pike, Ralls50 min
Jun 20, 10:22 PM CDTSevere Thunderstorm WarningLSXAudrain, Boone, Callaway38 min
Jun 20, 10:27 PM CDTAreal Flood AdvisoryLSXAudrain, Boone, Monroe3 hr
Jun 20, 10:42 PM CDTSevere Thunderstorm WarningLSXBoone, Callaway, Cole, Moniteau48 min
Jun 20, 10:55 PM CDTSevere Thunderstorm WarningLSXAudrain, Boone, Callaway, Montgomery35 min
Jun 20, 11:29 PM CDTSevere Thunderstorm WarningLSXBoone, Callaway, Cole, Franklin, Gasconade, Lincoln and 3 more31 min
Jun 20, 11:41 PM CDTSevere Thunderstorm WarningLSXLincoln, Saint Charles19 min
Jun 20, 11:59 PM CDTSevere Thunderstorm WarningLSXFranklin, Gasconade, Montgomery, Osage, Warren31 min
Jun 21, 12:34 AM CDTSevere Thunderstorm WarningLSXBoone, Callaway, Cole, Moniteau26 min

Nearby

Severe Thunderstorm Warnings in Missouri, 2021Severe Thunderstorm Warnings in Illinois, 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.