Storms developed along an old outflow boundary over portions of southwest Illinois. Some of the storms became strong to severe with damaging winds reported.
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Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS LSX wrote it up.
Storms developed along an old outflow boundary over portions of southwest Illinois. Some of the storms became strong to severe with damaging winds reported.
The local office's own words before the first event, 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 the first event at Jul 5, 1:10 PM CST, 35 minutes earlier.
Area Forecast Discussion National Weather Service Saint Louis MO 210 PM CDT Wed Jul 5 2023 .SHORT TERM... (Through Late Thursday Night) Issued at 209 PM CDT Wed Jul 5 2023 Thunderstorms have developed across the central CWA along a old outflow boundary early this afternoon. Expect storms to continue to develop along and ahead of the this boundary into the early evening as MLCAPES will be in the 2000-3000 J/kg range. Deep layer shear is weak which does not support organized convection, but there is a weakening MCV moving across the area that is helping to generate the lift for the storms. The SPC microburst composite and hail parameters are both suggest the potential for isolated severe thunderstorms through early this evening. Surface analysis is showing the actual cold front over eastern Iowa and northwest Missouri. Latest RAP has this front moving southeast through the CWA tonight. Expect most of the rain to move east and south of the area by late this evening. Will keep with a chance of showers and thunderstorms over parts of central and southeast Missouri into southwest Illinois on Thursday as the GFS/NAM are showing a weak shortwave trough moving quickly from the central Plains into the mid South. Lows tonight will be close to normal and temperatures on Thursday and Thursday night will be a bit below normal with cold air advection behind the front. Britt .LONG TERM... (Friday through Next Wednesday) Issued at 209 PM CDT Wed Jul 5 2023 There is good agreement amongst the ensembles that the upper pattern will become more amplified over the weekend into early next week as an upper ridge builds over the Rockies and a upper low deepens near Hudson Bay. This will cause the quasi-zonal flow over the area on Friday to turn northwesterly by early next week. Within this flow, the deterministic models are showing multiple shortwave troughs moving through Missouri and Illinois Friday through Sunday with a surface trough moving across the area on Saturday. Will keep chances for showers and thunderstorms going through the weekend with likely/categorical PoPs Friday night into Saturday. Chances will be lower Monday into Tuesday as a surface high moves across the area before another trough moves into the area by the middle of next week. Temperatures Friday through Sunday will likely be below normal with the clouds and the chance for rain. Highs will be climb closer to normal by next week as 850mb temperatures climb into the 15-20C range and the surface flow turns out of the southwest. This is reflected well in the ensemble temperature plumes including the NBM. Britt && .AVIATION... (For the 18z TAFs through 18z Thursday Afternoon) Issued at 1220 PM CDT Wed Jul 5 2023 There will be a 2-4 hour window of thunderstorms early in the period at UIN, STL, SUS, and CPS. These thunderstorms will likely produce brief MVFR, possible IFR ceilings and visibilities in heavy rain. Otherwise, mainly dry and VFR conditions are expected the rest of the period with winds turning out of the west to northwest around 8 knots. Britt && .LSX WATCHES/WARNINGS/ADVISORIES... MO...None. IL...None. && WFO LSX
Hazardous Weather Outlook National Weather Service St Louis MO 240 PM CDT Wed Jul 5 2023 ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027- 034>036-041-042-047>052-059>065-072>075-084-085-099-061945- 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- 240 PM CDT Wed Jul 5 2023 This Hazardous Weather Outlook is for portions of eastern and central Missouri as well as west central and southwest Illinois. .DAY ONE...Tonight. Isolated severe storms are possible through early this evening over parts southwest Missouri and southwest and south central Illinois. The main threat will be damaging winds, with large hail also possible. .DAYS TWO THROUGH SEVEN...Thursday through Tuesday. There is a chance for thunderstorms Thursday. Then another chance for thunderstorms Friday afternoon through Tuesday. .SPOTTER INFORMATION STATEMENT... Spotter activation may be needed through this evening. Britt
The St Louis radar (KLSX), 98 km away, was scanning. The volume nearest the first event began at 19:45 UTC.
1 thunderstorm wind. Local standard time, as filed.
Thunderstorm winds blew down several large trees and numerous tree limbs on the White Oaks Golf Course.
After NWS Directive 10-1605, the rules offices file Storm Data by.
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NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 1127639.