A strong shortwave moved through the region, triggering showers and thunderstorms. There were numerous reports of large hail and one report of flash flooding with these storms.
Every event with a place to put it. Tap one for its entry below.
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.
A strong shortwave moved through the region, triggering showers and thunderstorms. There were numerous reports of large hail and one report of flash flooding with these storms.
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 Mar 15, 2:29 PM CST, 2 hours 12 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE ST LOUIS MO 329 PM CDT THU MAR 15 2012 .SHORT TERM... ISSUED AT 325 PM CDT THU MAR 15 2012 (TONIGHT) MAIN CONVECTIVE THREAT SHOULD BE THIS EVENING...AND PRIMARILY OVER S SECTIONS OF THE CWA...ALONG AND AHEAD OF BLOSSOMING CONVECTION ACROSS THE OZARKS. MEANWHILE...HAVE CONTINUED CHANCE POPS OVER N SECTIONS OF THE FA. NOT CERTAIN THAT MUCH PRECIP WILL BE ABLE TO DEVELOP THAT FAR N...BUT INSTABILITY...LOW CIN...AND UPSTREAM SHORTWAVE WARRANTS CONTINUING MENTION OF TSRA. TEMPERATURES SHOULD REMAIN UNSEASONABLY MILD...AND RANGE FROM THE UPPER 50S TO LOWER 60S. TRUETT && .LONG TERM... ISSUED AT 259 PM CDT THU MAR 15 2012 (FRIDAY THROUGH NEXT THURSDAY) NOT MUCH HAS CHANGED IN MDL SOLNS FROM YESTERDAY. MDLS STILL SUGGEST REGION REMAINS IN A SIMILAR AIRMASS INTO THE WEEKEND. MDLS PROG H85 TEMPS TO REMAIN IN THE 12C TO 14C RANGE. SCT TSRA DURING THE AFTERNOON INTO THE EVENING AND AGAIN JUST BEFORE AND AFTER SUNRISE. HAVE THEREFORE KEPT PERSISTENCE FORECAST GOING INTO SUN WITH ONLY MINOR TWEAKS FROM DAY TO DAY. SAT NIGHT DOES HAVE SOME UNCERTAINTY REGARDING TEMPS/POPS. MDLS CONTINUE TO DEPICT MCS/MCV ON SAT INTO SAT NIGHT MOVING NEWD INTO/NEAR THE CWA. MDLS AGREE ON THE OCCURRENCE OF THIS FEATURE. HOWEVER...TIMING AND TRACK DIFFER. TEMPS ON SAT AND POSSIBLY INTO SUN WILL GREATLY DEPEND ON WHICH SOLN VERIFIES. LIKEWISE...THE GOING MAX TEMPS ARE BASED ON EXPECTING ISOD TO SCT TSRA...DEPENDING ON LOCATION IN THE CWA. BELIEVE BEST CHANCES FOR MULTICELL CLUSTERS WILL BE OUTSIDE OF THE CWA. HOWEVER...IF THE LOCATION CHANGES...TEMPS WILL HAVE TO BE ALTERED IN FUTURE UPDATES TO ACCOUNT FOR THIS. AS FOR SVR CHANCES...WITH SAME THINKING AS MENTIONED ABOVE...AN ISOD SVR TSRA WILL BE POSSIBLE INTO THE WEEKEND. MDLS PROG MLCAPE AROUND 2000 J/KG WITH STEEP MID LVL LAPSE RATES. DEEP LAYER SHEER WILL BE DIMINISHED...LIMITING ORGANIZED THREAT. FOR THE EXTD...PERSISTENCE TRENDS CONTINUE EARLY INTO THE PERIOD. MDLS CONTINUE TO DEPICT LEE CYCLOGENESIS ON DEEP TROF CROSSING THE ROCKIES MON INTO TUES. THIS SYSTEM WILL BEGIN TO AFFECT THE CWA AS EARLY AS MON AND A NUMBER OF S/WS EJECT INTO THE PLAINS INCREASING THE CHANCE OF TSRA ACROSS THE AREA. MDLS AGREE WITH A CUT OFF LOW DEVELOPING AND EVENTUALLY IMPACTING THE CWA. HOWEVER...MDLS DISAGREE REGARDING TIMING. FOR NOW...HAVE CONTINUED LOWER END CHANCE POPS AND WILL INCREASE AS CONFIDENCE INCREASES. HAVE CONTINUED WARM TREND THRU THE EXTD PERIOD...BUT TEMPS ARE EXPECTED TO BE COOLER WED INTO THURS AS CUT OFF LOW APPROACHES AND SPREADS PRECIP/CLOUDS INTO THE REGION. TILLY && .AVIATION... ISSUED AT 1234 PM CDT THU MAR 15 2012 THIS MORNINGS CONVECTIVE CLUSTER PUSHING INTO S IL ATTM...SO FORECAST TRENDS FOR THIS AFTERNOON DEAL WITH REDEVELOPMENT IN THE WAKE OF THIS SYSTEM. AMS IS MODERATLY UNSTABLE WITH LITTLE CIN...SO EXPECT HIT AND MISS CONVECTION DURING THE AFTERNOON. ATTM NOT CERTAIN IF AND/OR WHERE THE MAIN COVERAGE OF THIS AFTERNOONS CONVECTION WILL BE...ALTHOUGH HRRR DATA HAS BEEN HINTING THAT THE SOMEWHAT BETTER FOCUS FOR STORMS WILL BE FROM THE EASTERN OZARKS THROUGH THE STL AREA. FOR NOW HAVE HIGHLIGHTED TS THREAT WITH CB CLOUD GROUP ALG AND S OF I-70 CORRIDOR. HAVE ALSO KEPT CB GROUP GOING INTO THE EVENING...AS THERE SEEMS TO BE SOME MODEL CONSENSUS THAT SHORTWAVE CURRENTLY OVER OK WILL KEEP SOME THREAT GOING PAST MAX HEATING. FINALLY...GIVEN PERSISTENT S FLOW AND CONDITIONS OVER THE PLAINS AROUND DAYBREAK THIS MORNING...HAVE INTRODUCED A BIT OF FOG AND STRATUS FOR EARLY FRIDAY MORNING...PRIMARILY IN UIN AND COU. SPECIFICS FOR KSTL...TAF ATTEMPTS TO REFLECT AN AMS-TYPE TSRA THREAT WITH A BKN CU FIELD...VCSH...AND CB CLOUD GROUP...AND WILL REFINE THIS IF/WHEN CONVECTIVE TRENDS BECOME A BIT BETTER DEFINED. AS MENTIONED ABOVE...HAVE ALSO HELD ONTO CB CLOUD GROUP PAST MAX HEATING AND THROUGHOUT THE EVENING DUE TO UPSTREAM SHORTWAVE. TRUETT && .CLIMATE... HERE ARE THE RECORD HIGH MAXIMUM AND HIGH MINIMUM TEMPERATURES FOR KSTL AND KCOU FOR THURSDAY 03/15 AND FRIDAY 03/16. KSTL DAY DATE HI MAX YEAR HI MIN YEAR THU 03/15 80F 1945 60F 1919 FRI 03/16 86F 1945 57F 1919 KCOU DAY DATE HI MAX YEAR HI MIN YEAR THU 03/15 79F 1914 62F 1919 FRI 03/16 87F 1945 55F 1945 && .PRELIMINARY POINT TEMPS/POPS... ST LOUIS 63 85 65 85 / 40 30 20 40 QUINCY 60 83 59 83 / 30 20 20 40 COLUMBIA 61 82 60 82 / 30 20 20 50 JEFFERSON CITY 61 82 63 82 / 30 20 20 50 SALEM 61 80 62 80 / 50 40 30 40 FARMINGTON 61 81 62 81 / 60 40 30 40 && .LSX WATCHES/WARNINGS/ADVISORIES... MO...NONE. IL...NONE. && WFO LSX
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE ST LOUIS MO 350 PM CDT THU MAR 15 2012 ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027- 034>036-041-042-047>052-059>065-072>075-084-085-099-161200- 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-ST. 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-ST. CHARLES MO-FRANKLIN MO- ST. LOUIS MO-ST. LOUIS CITY MO-JEFFERSON MO-CRAWFORD MO- WASHINGTON MO-ST. FRANCOIS MO-STE. GENEVIEVE MO-IRON MO- MADISON MO-REYNOLDS MO- 350 PM CDT THU MAR 15 2012 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 OF THUNDERSTORMS ACROSS THE AREA TONIGHT. SOME OF THE STORMS COULD BE STRONG TO SEVERE ACROSS PARTS OF CENTRAL... EAST CENTRAL AND SOUTHEAST MISSOURI AS WELL AS SOUTHWEST AND SOUTHERN ILLINOIS. THE PRIMARY SEVERE WEATHER THREAT WILL BE LARGE HAIL. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY THERE IS A CHANCE OF THUNDERSTORMS THURSDAY THROUGH SATURDAY AND AGAIN IN CENTRAL MISSOURI ON MONDAY AND OVERSPREADING THE AREA TUESDAY THROUGH WEDNESDAY. SOME OF THE STORMS ON FRIDAY MAY BE STRONG TO SEVERE ACROSS PARTS OF CENTRAL...EAST CENTRAL AND SOUTHEAST MISSOURI AS WELL AS SOUTHWEST AND SOUTHERN ILLINOIS. THE PRIMARY SEVERE WEATHER THREAT WILL BE LARGE HAIL. .SPOTTER INFORMATION STATEMENT... SPOTTERS ARE ASKED TO RELAY REPORTS OF SEVERE WEATHER AND FLASH FLOODING TO THE NATIONAL WEATHER SERVICE IN ST. LOUIS. TILLY
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
516 PM CDT THU MAR 15 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0500 PM HAIL PERSHING 38.58N 91.61W
03/15/2012 E0.88 INCH GASCONADE MO TRAINED SPOTTER
HAIL REPORTED BETWEEN MORRISON AND PERSHING MISSOURI.
&&
DYEPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
518 PM CDT THU MAR 15 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0516 PM HAIL 10 W HERMANN 38.70N 91.62W
03/15/2012 E0.88 INCH GASCONADE MO TRAINED SPOTTER
&&
DYEPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
524 PM CDT THU MAR 15 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0523 PM HAIL 1 NW HIGH HILL 38.89N 91.39W
03/15/2012 M1.00 INCH MONTGOMERY MO STORM CHASER
PEA TO QUARTER SIZE HAIL ON I-70 WEST OF HWY 19
&&
KANOFSKYPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
525 PM CDT THU MAR 15 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0524 PM HAIL DRAKE 38.47N 91.47W
03/15/2012 M0.75 INCH GASCONADE MO TRAINED SPOTTER
&&
KANOFSKYPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
527 PM CDT THU MAR 15 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0527 PM HAIL NEW FLORENCE 38.91N 91.45W
03/15/2012 M0.88 INCH MONTGOMERY MO TRAINED SPOTTER
&&
KANOFSKYPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
536 PM CDT THU MAR 15 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0411 PM HAIL LAKE ST. LOUIS 38.79N 90.78W
03/15/2012 M2.25 INCH ST. CHARLES MO 911 CALL CENTER
MEASURED AT HWY N AND WYNDGATE RIDGE DR
&&
KANOFSKYThe St Louis radar (KLSX), 71 km away, was scanning. The volume nearest the first event began at 22:38 UTC.
2 hail. Local standard time, as filed.
Numerous reports of large hail were reported in Carrollton. The largest hail stones were baseball size.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Illinois in 2012Every state in 2012This day in weather historyWarnings in Illinois, March 2012
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: 370435, 370439.