Alert archive / Missouri / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 138, NWS St. Louis, MO

August 8, 2021Franklin County, Gasconade County, Missouri

NWS St. Louis, MO issued this severe thunderstorm warning at Aug 8, 2021, 2:43 PM CDT for Franklin County, Gasconade County, 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
Aug 8, 2021, 2:43 PM CDT (19:43 UTC)
Expired
Aug 8, 2021, 3:30 PM CDT
In force
47 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Franklin County, MO, Gasconade County, MO

The radar

The St Louis radar (KLSX), 50 km from the middle of the area, began a volume at 19:45 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
Aug 8, 3:18 PM CDTTSTM WND DMG5 Wsw Washington, MOSEVERAL TREES AND TREE LIMBS BLOWN DOWN.

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
Aug 8, 12:44 PM CDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 7.7 hours before the alert went out and 289 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 12:00Z on 2021-08-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 310 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 12:00Z on 2021-08-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -25 square meters per square second.1939Sfc1 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
310 J/kg
Mixed-layer CIN
-97 J/kg
Mixed-layer LCL
1165 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
-25 m²/s²
0-3 km storm-relative helicity
-3 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

060 
WUUS53 KLSX 081943
SVRLSX
MOC071-073-082030-
/O.NEW.KLSX.SV.W.0138.210808T1943Z-210808T2030Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service St Louis MO
243 PM CDT Sun Aug 8 2021

The National Weather Service in St Louis has issued a

* Severe Thunderstorm Warning for...
  Franklin County in east central Missouri...
  Southeastern Gasconade County in east central Missouri...

* Until 330 PM CDT.

* At 243 PM CDT, severe thunderstorms were located along a line
  extending from near Rosebud to 9 miles northwest of Bourbon, moving
  northeast at 35 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.

* Severe thunderstorms will be near...
  Gerald around 255 PM CDT.

Other locations in the path of these severe thunderstorms include
Beaufort, Washington, St. Clair, Parkway and Union.

This includes Interstate 44 in Missouri between exits 230 and 247.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

To report severe weather, contact your nearest law enforcement
agency. They will send your report to the National Weather Service
office in St Louis.

&&

LAT...LON 3858 9131 3861 9120 3860 9113 3861 9106
      3860 9104 3857 9102 3854 9096 3834 9085
      3821 9136 3821 9148 3837 9151
TIME...MOT...LOC 1943Z 241DEG 31KT 3838 9144 3822 9141 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Gosselin
1 follow-up statement
850 
WWUS53 KLSX 082006
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
306 PM CDT Sun Aug 8 2021

MOC073-082016-
/O.CAN.KLSX.SV.W.0138.000000T0000Z-210808T2030Z/
Gasconade MO-
306 PM CDT Sun Aug 8 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN GASCONADE 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 800 PM CDT for
east central Missouri.

LAT...LON 3858 9131 3861 9120 3860 9113 3861 9106
      3860 9104 3857 9102 3854 9096 3834 9085
      3821 9137 3852 9137
TIME...MOT...LOC 2006Z 241DEG 31KT 3847 9123 3831 9120 

$$

MOC071-082030-
/O.CON.KLSX.SV.W.0138.000000T0000Z-210808T2030Z/
Franklin MO-
306 PM CDT Sun Aug 8 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 330 PM CDT
FOR FRANKLIN COUNTY...

At 306 PM CDT, severe thunderstorms were located along a line
extending from near Beaufort to 6 miles north of Sullivan, moving
northeast at 35 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, St. Clair, Parkway and Union.

This includes Interstate 44 in Missouri between exits 239 and 247.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
St Louis.

&&

LAT...LON 3858 9131 3861 9120 3860 9113 3861 9106
      3860 9104 3857 9102 3854 9096 3834 9085
      3821 9137 3852 9137
TIME...MOT...LOC 2006Z 241DEG 31KT 3847 9123 3831 9120 

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

$$

Gosselin

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 8, 2:37 PM CDTHeat AdvisoryLSXAudrain, Boone, Callaway, Cole, Crawford, Franklin and 23 more4 days
Aug 8, 3:19 PM CDTSevere Thunderstorm WarningLSXFranklin, Lincoln, Saint Charles, Warren41 min
Aug 8, 3:54 PM CDTSevere Thunderstorm WarningLSXLincoln, Saint Charles66 min
Aug 8, 4:35 PM CDTAreal Flood AdvisoryLSXRalls3 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.