Alert archive / Missouri / Tornado Warnings in 2024

Tornado Warning 49, NWS St. Louis, MO

May 7, 2024Calhoun County, Illinois; Saint Charles County, Saint Louis County, Missouri

NWS St. Louis, MO issued this tornado warning at May 7, 2024, 4:23 AM CDT for Calhoun County, Illinois; Saint Charles County, Saint Louis County, Missouri. It was in force for 37 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 7, 2024, 4:23 AM CDT (09:23 UTC)
Expired
May 7, 2024, 5:00 AM CDT
In force
37 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Tornado
Radar indicated
Hail
0.75 in

Counties Calhoun County, IL, Saint Charles County, MO, Saint Louis County, MO

The radar

The St Louis radar (KLSX), 3 km from the middle of the area, began a volume at 09:23 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 7, 12:53 AM CDTTornado WatchSPC7 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 9.4 hours before the alert went out and 239 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 00:00Z on 2024-05-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 4 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 00:00Z on 2024-05-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -9 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
4 J/kg
Mixed-layer CIN
-9 J/kg
Mixed-layer LCL
937 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
-9 m²/s²
0-3 km storm-relative helicity
120 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

The text

As transmitted.

158 
WFUS53 KLSX 070923
TORLSX
ILC013-MOC183-189-071000-
/O.NEW.KLSX.TO.W.0049.240507T0923Z-240507T1000Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service St Louis MO
423 AM CDT Tue May 7 2024

The National Weather Service in St Louis has issued a

* Tornado Warning for...
  Southern Calhoun County in southwestern Illinois...
  Western St. Charles County in east central Missouri...
  Northwestern St. Louis County in east central Missouri...

* Until 500 AM CDT.

* At 423 AM CDT, a severe thunderstorm capable of producing a 
  tornado was located over mainly rural areas of St Charles County, 
  moving northeast at 45 mph.

  HAZARD...Tornado.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* This dangerous storm will be near...
  O'Fallon, St. Peters, Chesterfield, Dardenne Prairie, Weldon 
  Spring, Cottleville, and Weldon Spring Heights around 430 AM CDT.
  St. Charles and Harvester around 435 AM CDT.
  Bridgeton around 440 AM CDT.

Other locations in the path of this tornadic thunderstorm include
Hazelwood.

This also includes First Missouri State Capitol Historic Site.
 
This includes Interstate 70 in Missouri between exits 216 and 231.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 3876 9036 3862 9073 3864 9073 3861 9076
      3859 9082 3871 9092 3894 9053
TIME...MOT...LOC 0923Z 237DEG 40KT 3869 9077 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...<.75 IN

$$

Elmore
3 follow-up statements
173 
WWUS53 KLSX 070932
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
Issued by National Weather Service Kansas City/Pleasant Hill MO
432 AM CDT Tue May 7 2024

ILC013-MOC183-189-071000-
/O.CON.KLSX.TO.W.0049.000000T0000Z-240507T1000Z/
Calhoun IL-St. Charles MO-St. Louis MO-
432 AM CDT Tue May 7 2024

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 500 AM CDT FOR SOUTHERN
CALHOUN...CENTRAL ST. CHARLES AND NORTHWESTERN ST. LOUIS COUNTIES...

At 431 AM CDT, a severe thunderstorm capable of producing a tornado
was located over Weldon Spring Heights, moving northeast at 40 mph.

HAZARD...Tornado.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

This dangerous storm will be near...
  O'Fallon, St. Peters, Chesterfield, Dardenne Prairie, Weldon 
  Spring, Cottleville, Spirit of St. Louis Airport, Weldon Spring 
  Heights, and Harvester around 435 AM CDT.
  St. Charles and Maryland Heights around 440 AM CDT.

Other locations in the path of this tornadic thunderstorm include
Bridgeton, Champ, Hazelwood and Lambert-St. Louis International
Airport.

This also includes First Missouri State Capitol Historic Site.
 
This includes Interstate 70 in Missouri between exits 217 and 231.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 3876 9036 3863 9072 3873 9082 3893 9052
TIME...MOT...LOC 0931Z 242DEG 35KT 3870 9069 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...<.75 IN

$$

BMW
214 
WWUS53 KLSX 070942
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
442 AM CDT Tue May 7 2024

ILC013-MOC183-189-071000-
/O.CON.KLSX.TO.W.0049.000000T0000Z-240507T1000Z/
Calhoun IL-St. Charles MO-St. Louis MO-
442 AM CDT Tue May 7 2024

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 500 AM CDT FOR SOUTHERN
CALHOUN...CENTRAL ST. CHARLES AND NORTHWESTERN ST. LOUIS COUNTIES...

At 441 AM CDT, a severe thunderstorm capable of producing a tornado
was located over Harvester, moving northeast at 45 mph.

HAZARD...Tornado.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

This dangerous storm will be near...
  St. Charles, St. Peters, Maryland Heights, Hazelwood, Bridgeton, 
  and Champ around 445 AM CDT.

This also includes First Missouri State Capitol Historic Site.
 
This includes Interstate 70 in Missouri between exits 219 and 231.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 3876 9036 3867 9061 3881 9070 3893 9052
TIME...MOT...LOC 0941Z 237DEG 40KT 3876 9056 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...<.75 IN

$$

Elmore
301 
WWUS53 KLSX 070956
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
456 AM CDT Tue May 7 2024

ILC013-MOC183-189-071006-
/O.EXP.KLSX.TO.W.0049.000000T0000Z-240507T1000Z/
Calhoun IL-St. Charles MO-St. Louis MO-
456 AM CDT Tue May 7 2024

...THE TORNADO WARNING FOR SOUTHERN CALHOUN...CENTRAL ST. CHARLES AND
NORTHWESTERN ST. LOUIS COUNTIES WILL EXPIRE AT 500 AM CDT...

The storm which prompted the warning has weakened below severe
limits, and no longer appears capable of producing a tornado.
Therefore, the warning will be allowed to expire.

A Tornado Watch remains in effect until 800 AM CDT for southwestern
Illinois...and east central Missouri.

&&

LAT...LON 3876 9036 3867 9061 3881 9070 3893 9052
TIME...MOT...LOC 0956Z 237DEG 40KT 3883 9042 

$$

Elmore

The office that day

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

IssuedProductOfficeCountiesLasted
May 7, 4:05 AM CDTSevere Thunderstorm WarningLSXMonroe40 min
May 7, 4:58 AM CDTSevere Thunderstorm WarningLSXRandolph47 min
May 7, 5:03 AM CDTSevere Thunderstorm WarningLSXGreene, Macoupin, Montgomery42 min
May 7, 5:37 AM CDTSevere Thunderstorm WarningLSXRandolph15 min
May 7, 1:12 AM CDTSevere Thunderstorm WarningLSXCole, Moniteau78 min
May 7, 1:25 AM CDTSevere Thunderstorm WarningLSXAudrain, Boone, Callaway, Monroe80 min
May 7, 2:05 AM CDTSevere Thunderstorm WarningLSXKnox, Shelby70 min
May 7, 2:15 AM CDTSevere Thunderstorm WarningLSXOsage60 min
May 7, 2:19 AM CDTSevere Thunderstorm WarningLSXMonroe41 min
May 7, 2:34 AM CDTTornado WarningLSXKnox14 min
May 7, 2:41 AM CDTSevere Thunderstorm WarningLSXAudrain, Callaway, Montgomery64 min
May 7, 2:57 AM CDTTornado WarningLSXAudrain, Ralls17 min
May 7, 2:59 AM CDTSevere Thunderstorm WarningLSXCrawford, Franklin, Gasconade, Osage46 min
May 7, 3:06 AM CDTSevere Thunderstorm WarningLSXLincoln, Pike, Warren54 min
May 7, 3:09 AM CDTSevere Thunderstorm WarningLSXCrawford36 min
May 7, 3:27 AM CDTSevere Thunderstorm WarningLSXIron, Reynolds, Washington63 min
May 7, 3:41 AM CDTSevere Thunderstorm WarningLSXFranklin49 min
May 7, 3:49 AM CDTTornado Warning Tornado observedLSXCrawford, Franklin, Washington26 min
May 7, 4:13 AM CDTSevere Thunderstorm WarningLSXSainte Genevieve, Saint Francois47 min
May 7, 4:16 AM CDTSevere Thunderstorm WarningLSXSaint Charles, Warren44 min
May 7, 4:20 AM CDTSevere Thunderstorm WarningLSXIron, Reynolds, Washington40 min
May 7, 4:48 AM CDTSevere Thunderstorm WarningLSXMadison, Saint Francois42 min

Nearby

Tornado Warnings in Missouri, 2024Tornado Warnings in Illinois, 2024Every tornado warning in 2024Tornadoes in 2024

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.