Alert archive / Illinois / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 234, NWS St. Louis, MO

July 4, 2023Lincoln County, Pike County, Missouri; Calhoun County, Greene County, Jersey County, Illinois

NWS St. Louis, MO issued this severe thunderstorm warning at Jul 4, 2023, 6:56 PM CDT for Lincoln County, Pike County, Missouri; Calhoun County, Greene County, Jersey County, Illinois. It was in force for 31 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jul 4, 2023, 6:56 PM CDT (23:56 UTC)
Expired: Jul 4, 2023, 7:27 PM CDT
In force: 31 min
Issued by: NWS St. Louis, MO
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Calhoun County, IL, Greene County, IL, Jersey County, IL, Lincoln County, MO, Pike County, MO

The radar

The St Louis radar (KLSX), 56 km from the middle of the area, began a volume at 23:57 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 nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 11.9 hours before the alert went out and 209 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 674 J/kg
Mixed-layer CIN: -45 J/kg
Mixed-layer LCL: 1166 m above ground
0-6 km bulk shear: 9 kt
0-1 km storm-relative helicity: -22 m²/s²
0-3 km storm-relative helicity: -11 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS St. Louis, MO wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 4, 6:56 PM CDT, 0 minutes earlier.

Area forecast discussion, Jul 4, 6:56 PM CDT, 0 minutes before

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Hazardous weather outlook, Jul 4, 2:36 PM CDT, 4 hours 20 minutes before

Hazardous Weather Outlook
National Weather Service St Louis MO
236 PM CDT Tue Jul 4 2023

ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027-
034>036-041-042-047>052-059>065-072>075-084-085-099-051945-
Greene IL-Macoupin IL-Montgomery IL-Bond IL-Fayette IL-Clinton IL-
Marion IL-Washington IL-Randolph IL-Adams IL-Brown IL-Pike IL-
Calhoun IL-Jersey IL-Madison IL-Saint Clair IL-Monroe IL-Knox MO-
Lewis MO-Shelby MO-Marion MO-Monroe MO-Ralls MO-Pike MO-Boone MO-
Audrain MO-Moniteau MO-Cole MO-Osage MO-Callaway MO-Montgomery MO-
Lincoln MO-Gasconade MO-Warren MO-Saint Charles MO-Franklin MO-
Saint Louis MO-Saint Louis City MO-Jefferson MO-Crawford MO-
Washington MO-Saint Francois MO-Sainte Genevieve MO-Iron MO-
Madison MO-Reynolds MO-
236 PM CDT Tue Jul 4 2023

This Hazardous Weather Outlook is for portions of eastern and
central Missouri as well as west central and southwest Illinois.

.DAY ONE...Tonight.

There is a chance for thunderstorms through early evening. Isolated
strong to severe thunderstorms may produce damaging winds to 60 mph
or hail to the size of quarters over southeast Missouri.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday.

There is a slight risk of strong to severe storms Wednesday into
Wednesday night. The main threat will be damaging winds, with large
hail also possible.

There is a chance for thunderstorms Thursday. Then another chance
for thunderstorms Friday afternoon through Monday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be required through early this evening.

Britt

In the hours before

Local storm report, Jul 4, 2:22 PM CDT, 4 hours 34 minutes before

Preliminary Local Storm Report
National Weather Service St Louis MO
222 PM CDT Tue Jul 4 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0220 PM     Rain             1 ESE Mapaville         38.24N 90.46W
07/04/2023  M0.38 inch       Jefferson          MO   Trained Spotter

            Wind gusts also to 40 mph.

&&

Britt

Local storm report, Jul 4, 2:47 PM CDT, 4 hours 9 minutes before

Preliminary Local Storm Report
National Weather Service St Louis MO
247 PM CDT Tue Jul 4 2023

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0242 PM     Rain             Chester                 37.91N 89.82W
07/04/2023  E0.70 inch       Randolph           IL   Emergency Mngr

            Dime size hail.

&&

Britt

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 4, 1:38 PM CDT	Severe Thunderstorm Warning	LSX	Sainte Genevieve	37 min
Jul 4, 6:00 PM CDT	Areal Flood Advisory	LSX	Saint Francois, Washington	115 min
Jul 4, 2:22 PM CDT	Severe Thunderstorm Warning	LSX	Randolph	23 min
Jul 4, 4:45 PM CDT	Severe Thunderstorm Warning	LSX	Macoupin	30 min

Nearby

Severe Thunderstorm Warnings in Illinois, 2023 Severe Thunderstorm Warnings in Missouri, 2023 Every severe thunderstorm warning in 2023

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.