Isolated severe storms developed across the region. A few reports of damaging winds and small hail were reported.
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.
Isolated severe storms developed across the region. A few reports of damaging winds and small hail were 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 Sep 10, 11:55 AM CST, 2 hours earlier.
AREA FORECAST DISCUSSION...UPDATED AVIATION NATIONAL WEATHER SERVICE ST LOUIS MO 1255 PM CDT THU SEP 10 2015 .UPDATE: Issued at 1207 PM CDT Thu Sep 10 2015 As soon as I hit SEND on AFD update, narrow band of spotty convection reformed south of STL, so will go with low PoPs over southern sections of the FA into mid afternoon. Otherwise, main concern turns to possible development over northern sections of the CWA for the afternoon hours with the approach of the cold front/wind shift. AMS has heated nicely over this part of the FA, and this instability combined with some UVV associated with weak shortwave will pose a threat of scattered convection. However, believe that these storms will not necessarily be the start of the shower and thunderstorm threat for the overnight hours, and think primary pops for tonight will be tied to growth and eventual eastward expansion of late afternoon and early evening convection that forms over eastern KS and western MO. Both GFS and NAM are showing pronounced divergence associated with RRQ of upper level jet back building into northern sections of the FA, with associated increase of SW/W low level jet from s KS and n OK into western MO. Truett && .SHORT TERM: (Through Tonight) Issued at 347 AM CDT Thu Sep 10 2015 Early morning fog across parts of MO/IL should mix out by mid to late morning. A broad shortwave trough moving across the region will drive a cdfnt through the CWA tonight and tomorrow. Instability ahead of the front along with H7-H5 lapse rates of ~6 deg C/km support a chance of thunderstorms this afternoon. Thunderstorm chances continue tonight, possibly in the form of an MCS developing upstream and moving into southwestern/central MO after 03z based on model forecasts of H85 moisture convergence and MUCAPE values of around 500-1000 J/kg. Kanofsky .LONG TERM: (Tomorrow through Wednesday) Issued at 347 AM CDT Thu Sep 10 2015 Cooler post-frontal temperatures are expected beginning Friday night when lows in the mid 40s to low 50s will be around 5-10 degrees below average. High pressure then builds across the central CONUS on Saturday into Sunday. Daytime highs on Saturday will be around 10-15 degrees below average. A vort max is fcst to dive down the back side of the sharpening trough on Saturday. There is good model agreement on the existence of this feature but poor agreement on its speed and location. This feature could support some instability sprinkles or showers across the eastern CWA on Saturday given a pocket of cold air aloft leading to fcst H7-H5 lapse rates of 6-6.5 deg C/km. On Saturday night/Sunday morning, good radiational cooling conditions along with the surface high pressure center located nearly overhead should produce overnight lows in the mid 40s (upper 40s in the St. Louis metro), which is around 10 degrees below average. The upper trough then closes off over the eastern CONUS on Sunday and slowly shifts eastward. By early next week, surface winds turn southerly/southwesterly around the back side of the aforementioned high pressure center which by that time should be centered over the Ohio Valley, and temperatures start to moderate. Uncertainty increases early/mid next week because the ECMWF/GFS disagree after 00z Tuesday on the evolution of a low pressure system over the Pacific NW. Kanofsky && .AVIATION: (For the 18z TAFs through 18z Friday Afternoon) Issued at 1255 PM CDT Thu Sep 10 2015 SCT to occasionally BKN CU field with bases aoa 4kft expected across the FA this afternoon. There appears to be two areas of potential convection for this afternoon...one is associated with weak convergence along cold front/surface trof that will be drifting into the KUIN area this afternoon, and have maintained VCTS for several hours in KUIN TAF in the late afternoon and early evening hours for this threat. Second area is isolated/AMS-type convection forming ahead of shortwave now entering STL Metro. Have maintained a dry forecast at all metro area TAFs for now, but getting a few cells forming to the NW of the area, and if they hold together/intensify may need to nowcast this threat into some of the metro TAFS. However, still believe the primary threat of convection during this TAF period will be late this evening and overnight, as discussed in Short-term AFD update. Like the trends suggested by the 15z HRRR, and have trended onset of precip and potential thunderstorm activity based on this output. Both NAM and GFS MOS suggest cigs lowering to IFR in the primary rain area along and I-70 corridor during the predawn hours...haven't gone quite this low, but given time of year and post-frontal cool air...low end MVFR certainly seems reasonable. Specifics for KSTL: Scattered CU with bases aoa 4kft expected this afternoon. AMS-type storms will dot the area, but will isolated coverage will monitor their trends and use nowcast techniques to determine if these will impact TAF area. Much larger of area of rain and embedded thunderstorms expected to work into the area after 06z, with ceilings in the stratus and rain deteriorating to low-end MVFR by daybreak Friday. Truett && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && WFO LSX
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE ST LOUIS MO 416 AM CDT THU SEP 10 2015 ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027- 034>036-041-042-047>052-059>065-072>075-084-085-099-110000- 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- 416 AM CDT THU SEP 10 2015 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EASTERN AND CENTRAL MISSOURI AS WELL AS WEST CENTRAL AND SOUTHWEST ILLINOIS. .DAY ONE...TODAY AND TONIGHT THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON AND TONIGHT. A FEW STORMS COULD PRODUCE GUSTY WINDS AND SMALL HAIL. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY THUNDERSTORMS ARE POSSIBLE ON FRIDAY AND ON WEDNESDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT ANTICIPATED TONIGHT. KANOFSKY
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
240 PM CDT THU SEP 10 2015
ILZ079-102-MOZ075-102030-
RANDOLPH IL-MONROE IL-STE. GENEVIEVE MO-
240 PM CDT THU SEP 10 2015
...SIGNIFICANT WEATHER ADVISORY FOR CENTRAL RANDOLPH...MONROE AND
NORTHEASTERN STE. GENEVIEVE COUNTIES UNTIL 330 PM CDT...
AT 240 PM CDT...DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM NEAR
WATERLOO...MOVING SOUTHEAST AT 50 MPH.
DIME SIZE HAIL AND WINDS IN EXCESS OF 40 MPH WILL BE POSSIBLE WITH
THIS STORM.
LOCATIONS IMPACTED INCLUDE...
WATERLOO...CHESTER...STE. GENEVIEVE...RED BUD...BREMEN...VALMEYER...
EVANSVILLE...ST. MARY...NEW DESIGN...PRAIRIE DU ROCHER...PRAIRIE...
ELLIS GROVE...RUMA...MAEYSTOWN...ROCKWOOD...FULTS...KASKASKIA...
FOSTER POND...KIDD AND RENAULT.
THIS INCLUDES INTERSTATE 55 IN MISSOURI NEAR EXIT 141.
THIS WARNING ALSO INCLUDES FELIX VALLE HOUSE STATE PARK.
THIS STORM MAY INTENSIFY...SO BE CERTAIN TO MONITOR LOCAL RADIO AND
TV STATIONS...AS WELL AS LOCAL CABLE TV OUTLETS...FOR ADDITIONAL
INFORMATION AND POSSIBLE WARNINGS FROM THE NATIONAL WEATHER SERVICE.
LAT...LON 3785 8966 3784 8966 3782 8971 3785 8974
3785 8979 3787 8980 3788 8980 3791 8984
3787 8990 3787 8994 3783 8999 3831 9037
3841 9018 3788 8964
TIME...MOT...LOC 1940Z 324DEG 43KT 3830 9022
CARNEYPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
246 PM CDT THU SEP 10 2015
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0244 PM HAIL IMPERIAL 38.37N 90.38W
09/10/2015 E0.50 INCH JEFFERSON MO TRAINED SPOTTER
MOSTLY PEA SIZED HAIL...BUT A FEW THAT ARE MARBLE SIZE.
&&
BYRDThe St Louis radar (KLSX), 53 km away, was scanning. The volume nearest the first event began at 19:53 UTC.
1 thunderstorm wind. Local standard time, as filed.
Thunderstorm winds blew down several trees on Front Street near intersection with Highway Z. One large tree fell onto power lines.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Missouri in 2015Every state in 2015This day in weather historyWarnings in Missouri, September 2015
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: 603970.