Alert archive / Missouri / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 55, NWS St. Louis, MO

May 27, 2021Jefferson County, Sainte Genevieve County, Missouri; Monroe County, Randolph County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at May 27, 2021, 2:46 PM CDT for Jefferson County, Sainte Genevieve County, Missouri; Monroe County, Randolph County, Illinois. It was in force for 29 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
May 27, 2021, 2:46 PM CDT (19:46 UTC)
Expired
May 27, 2021, 3:15 PM CDT
In force
29 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Monroe County, IL, Randolph County, IL, Jefferson County, MO, Sainte Genevieve County, MO

The radar

The St Louis radar (KLSX), 81 km from the middle of the area, began a volume at 19:47 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
May 27, 11:26 AM CDTSevere Thunderstorm WatchSPC8 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 7.8 hours before the alert went out and 251 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 2021-05-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2021-05-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 130 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1679 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
130 m²/s²
0-3 km storm-relative helicity
150 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

872 
WUUS53 KLSX 271946
SVRLSX
ILC133-157-MOC099-186-272015-
/O.NEW.KLSX.SV.W.0055.210527T1946Z-210527T2015Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service St Louis MO
246 PM CDT Thu May 27 2021

The National Weather Service in St Louis has issued a

* Severe Thunderstorm Warning for...
  Monroe County in southwestern Illinois...
  Northwestern Randolph County in southwestern Illinois...
  Southeastern Jefferson County in east central Missouri...
  Northeastern Ste. Genevieve County in southeastern Missouri...

* Until 315 PM CDT.

* At 246 PM CDT, a severe thunderstorm was located over Festus,
  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.

* This severe thunderstorm will be near...
  New Design around 305 PM CDT.

Other locations in the path of this severe thunderstorm include Red
Bud and Evansville.

This includes Interstate 55 in Missouri between exits 162 and 180.
 
This also includes Gov. Dunklin's Grave Historic Site.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 3797 8995 3811 9053 3835 9047 3827 8992
      3826 8991 3825 8992 3823 8990 3822 8990
      3822 8986
TIME...MOT...LOC 1946Z 279DEG 40KT 3821 9042 

HAIL...1.00IN
WIND...60MPH
 
$$

Carney
1 follow-up statement
042 
WWUS53 KLSX 272012 RRA
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
312 PM CDT Thu May 27 2021

ILC133-157-MOC099-186-272022-
/O.EXP.KLSX.SV.W.0055.000000T0000Z-210527T2015Z/
Monroe IL-Randolph IL-Jefferson MO-Ste. Genevieve MO-
312 PM CDT Thu May 27 2021

...THE SEVERE THUNDERSTORM WARNING FOR MONROE...NORTHWESTERN
RANDOLPH...SOUTHEASTERN JEFFERSON AND NORTHEASTERN STE. GENEVIEVE
COUNTIES WILL EXPIRE AT 315 PM CDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  However gusty
winds and heavy rain are still possible with this thunderstorm.

A Severe Thunderstorm Watch remains in effect until 700 PM CDT for
southwestern Illinois...and southeastern and east central Missouri.

LAT...LON 3797 8995 3811 9053 3835 9047 3827 8992
      3826 8991 3825 8992 3823 8990 3822 8990
      3822 8986
TIME...MOT...LOC 2012Z 279DEG 40KT 3816 9005 

$$

Carney

The office that day

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

IssuedProductOfficeCountiesLasted
May 27, 11:13 AM CDTSevere Thunderstorm WarningLSXLincoln, Saint Charles, Warren47 min
May 27, 11:50 AM CDTSevere Thunderstorm WarningLSXFranklin, Lincoln, Saint Charles, Saint Louis, Warren, City of Saint Louis55 min
May 27, 12:39 PM CDTAreal Flood AdvisoryLSXFranklin, Jefferson, Saint Charles, Saint Louis, City of Saint Louis3 hr
May 27, 1:09 PM CDTSevere Thunderstorm WarningLSXFranklin, Saint Louis51 min
May 27, 1:24 PM CDTSevere Thunderstorm WarningLSXCrawford, Gasconade51 min
May 27, 1:51 PM CDTSevere Thunderstorm WarningLSXCrawford, Franklin, Washington39 min
May 27, 11:32 AM CDTSevere Thunderstorm WarningLSXGreene, Macoupin43 min
May 27, 12:07 PM CDTSevere Thunderstorm WarningLSXGreene, Macoupin, Montgomery38 min
May 27, 12:26 PM CDTTornado WarningLSXMacoupin, Madison34 min
May 27, 12:56 PM CDTTornado WarningLSXBond, Macoupin, Madison, Montgomery28 min
May 27, 2:16 PM CDTAreal Flood AdvisoryLSXBond, Fayette3 hr
May 27, 2:31 PM CDTSevere Thunderstorm WarningLSXClinton, Fayette, Marion44 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.