A quasi-stationary frontal boundary was the main focusing mechanism for a round of significant severe weather over the forecast area. A strong shortwave moved along the boundary triggering widespread showers and thunderstorms.
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 quasi-stationary frontal boundary was the main focusing mechanism for a round of significant severe weather over the forecast area. A strong shortwave moved along the boundary triggering widespread showers and thunderstorms. Numerous reports of large hail, damaging winds and 22 tornadoes occurred with this system.
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 Feb 27, 5:50 PM CST, 40 minutes earlier.
AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
550 PM CST SUN FEB 27 2011
.DISCUSSION...
/345 PM CST SUN FEB 27 2011/
THERE BE A PLETHORA OF WX HAZARDS TO DEAL WITH OVER THE NEXT 24HRS.
FIRST WILL BE THE SVR WX THREAT. A STRENGTHENING FRONTAL ZONE FROM
JUST S OF KPPQ TO KMYJ WILL REMAIN QUASI-STATIONARY THRU THE EVENING
HRS BEFORE MAKING ITS FINAL PUSH SEWD THRU THE FA. STEEP MID LEVEL
LAPSE RATES...ONLY KEPT AT BAY BY A STOUT CAP...BUT THAT WILL NOT BE
MUCH OF AN ISSUE SOON AS DEEP LIFT FROM A STRONG SHORTWAVE LIFTS
THIS LAYER AND REMOVES THE CAP. THIS SHOULD BE ALL COMING TOGETHER
AROUND 00Z AND WILL CONTINUE THRU THE EVENING AND INTO THE EARLY
OVERNIGHT. FOR MOST AREAS IN THE NRN FA...ROUGHLY N OF I-70...THE
PRIMARY THREAT WILL BE LARGE HAIL WITH A BRIEF SPINUP TORNADO
POSSIBLE WITH ANY SUPERCELLS THAT CROSS THE LO LEVEL FRONTAL ZONE.
FOR THE I-70 CORRIDOR AND AREAS S...A GREATER THREAT FOR DAMAGING
WINDS WILL EXIST TO ACCOMPANY THE LARGE HAIL...AS WELL AS TORNADOES.
THE MODELS STILL HAVE SOME ISSUES WITH EXACT STRUCTURE OF THE
SYSTEM...BUT MOST AGREE THAT A SEPARATION OF PCPN AREAS WILL OCCUR
WITH THE NRN AREA EVOLVING INTO LESS THUNDER AND MORE STRATIFORM
RAIN WITH TIME THIS EVENING AND WILL TEND TO BE A MORE STEADY ZONE
OF PCPN. THE SRN AREA WILL LIKELY GO THRU THE STL METRO AREA AND
AREAS TO THE S AND E...AND WILL BE THE PRIMARY SVR WX THREAT ZONE
WITH THIS SYSTEM. A DRY SLOT IS ULTIMATELY EXPECTED TO PUNCH THRU
LATE THIS EVENING AND EARLY OVERNIGHT AND WIND DOWN THE SVR THREAT
SIGNIFICANTLY.
ANOTHER HAZARD WILL BE FLOODING...AND AN AREAL FLOOD WATCH WAS
ISSUED EARLIER THIS AFTN FOR THE NRN FA TO ADDRESS SMALL CREEKS AND
STREAMS RUNNING OUT OF BANKFULL WITH THE EXPECTED INCH OR SO OF
RAINFALL THAT IS EXPECTED...IN ADDITION TO THE MELTING SNOW PACK AND
ALREADY SATURATED GROUND AND/OR STILL SOMEWHAT FROZEN GROUND
DEPENDING ON EXACTLY WHERE.
YET ANOTHER HAZARD IS DENSE FOG. THIS HAS FORMED WHERE MUCH HIGHER
DWPTS WITH FRONTAL ZONE HAVE INTERSECTED THE REMNANT SNOW PACK AND
PERSISTENT STRATUS TO CREATE A REGION OF POOR VSBYS. BELIEVE THIS
WILL PERSIST UNTIL THE FRONTAL ZONE BEGINS TO MAKE A GO TO THE
SOUTHEAST LATE THIS EVENING OR EARLY OVERNIGHT. DENSE FOG ADVISORY
HAS BEEN ISSUED.
AND FINALLY...SOME WINTRY WX IS EXPECTED AS THE SYSTEM PULLS OUT.
SOME IMPRESSIVE TEMP GRADIENTS EXIST ACROSS MO THANKS TO THIS
FRONTAL ZONE...FROM LOWER 30S JUST N OF IT TO NEAR 70 TO THE S. THIS
COLDER AIR WILL EXPAND SWD...BUT NOT TOO CONFIDENT THE COLD AIR WILL
GET MUCH STRONGER THAN WHAT IS ALREADY THERE AS IT APPEARS TO BE
TAPPED OUT. BELIEVE THE REGION OF LOW-MID 30S TEMPS WILL EXPAND SEWD
WITH THE ADVANCING FRONTAL ZONE LATER TONIGHT AND MONDAY AND THIS
WILL RESULT IN THE LEFTOVER PCPN CHANGING OVER TO SLEET OR SNOW AS
THE WARM WEDGE OF AIR ALOFT ERODES. SOME FZRA POSSIBLE...BUT BELIEVE
THE LACK OF A LARGE AREA OF SUB-FRZG TEMPS WILL LARGELY PRECLUDE
THAT BUT WILL MONITOR CLOSELY THIS EVENING. INITIAL SNOW ACCUMS WITH
SOME SLEET COULD BE NEAR AN INCH WHEN IT ENDS BY LATE MONDAY
MORNING.
DRY WX AND CLEAR SKIES WILL THEN TAKE HOLD FOR MONDAY NIGHT THRU
WEDNESDAY WITH NEAR OR SLIGHTLY ABOVE AVERAGE TEMPS. ANOTHER CDFNT
FOR TUESDAY NIGHT BUT THIS SHOULD PASS THRU WITH LITTLE FANFARE.
FOR THE EXTENDED PERIOD (WEDNESDAY NIGHT - SUNDAY)...ZONAL H500 FLOW
WILL GIVE WAY TO A STRONG SHORTWAVE HEADING INTO NEXT WEEKEND...BUT
THE 00Z/06Z MODELS ARE IN SHARP DISAGREEMENT ON HOW TO HANDLE IT AS
IT MOVES INTO THE CNTRL AND ERN CONUS. THE ECMWF WANTS TO CUT THIS
SYSTEM OFF AND SLOW IT DOWN AND DEEPEN IT OVER THE LOWER MS VALLEY
AND RESULT IN A PROLONGED PCPN EVENT FROM FRIDAY THRU THE END OF THE
PERIOD AT LEAST. THE GFS WANTS TO KEEP THINGS MORE PROGRESSIVE...
WHILE SLOWING DOWN THE TRANSLATIONAL SPEED SOME AND RESULT IN A PCPN
EVENT FROM FRIDAY UNTIL SATURDAY. PREFER THE GFS SOLUTION FOR NOW AS
IT HAS BETTER CONTINUITY AND ACKNOWLEDGES THE NEED TO SLOW THE
TIMING DOWN SOME IF THE SHORTWAVE DIGS AS DEEP AS NOW APPEARS IT
MIGHT...AND SO HAVE PUSHED THE CHANCES FOR RAIN BACK A BIT BUT KEPT
SUNDAY DRY. AT OR SLIGHTLY ABOVE AVERAGE TEMPS WILL ACCOMPANY THE
ZONAL FLOW AT THE BEGINNING OF THE PERIOD...BUT WILL BE CUT BACK TO
BELOW AVERAGE IN THE SECOND HALF OF THE PERIOD GIVEN EXPECTED CLOUDS
AND RAIN AND CDFNT MOVING THRU.
TES
&&
.AVIATION...
/550 PM CST SUN FEB 27 2011/
WARM FRONT HAS REMAINED SOUTH OF KUIN...SO WILL SEE DENSE FOG LINGER
FOR AT LEAST ANOTHER HOUR OR SO TIL THUNDERSTORM COMPLEX MOVES INTO
AREA. STILL SOME UNCERTAINTY ON WHERE THUNDERSTORMS WILL TRACK...SO
JUST KEPT VCTS MENTION FROM 01Z TO 05Z...THEN LINGERING RAIN ON
BACKSIDE OF SYSTEM CHANGING TO ALL SNOW BY 11Z BEFORE COMING TO AN
END AROUND 15Z. WILL SEE CIGS SCATTER OUT BY 21Z MON. AS FOR
WINDS...TO REMAIN FROM THE NORTH...THOUGH WILL SEE GUSTS TO NEAR
25KTS DURING THE DAY ON MONDAY...BEFORE DIMINISHING AS RIDGE BUILDS
IN. AS FOR KCOU...INITIAL COMPLEX MAY REMAIN NORTH OF TAF SITE...SO
FOR NOW JUST HAVE VCTS WITH ADDITIONAL ACTIVITY POSSIBLE TIL FRONT
MOVES THROUGH AROUND 05Z. THEN SEE LINGERING LIGHT RAIN...CHANGING
TO SNOW BY 12Z MON BEFORE COMING TO AN END. WINDS AT KCOU TO REMAIN
FROM THE SOUTH TIL FRONT MOVES THROUGH...THEN VEER TO THE NORTH.
PLEASE REFER TO THE STL DISCUSSION BELOW FOR SUS INFORMATION.
SPECIFICS FOR KSTL...
FOR STL METRO AREA...SOME SHOWERS AND STORMS HAVE DEVELOPED TO THE
SOUTHWEST OF AREA...BUT FEEL BEST CHANCES OF SEVERE WEATHER WILL BE
BETWEEN 04Z AND 07Z. ACTIVITY TO PERSIST OVER REGION THROUGH 09Z
WHEN COLD FRONT MOVES THROUGH. EXACT TIMING AND COVERAGE OF STORMS
STILL UNCERTAIN...SO FOR NOW JUST HAVE VCTS MENTIONED IN TAF...THEN
UPDATE AS NEEDED. ONCE FRONT MOVES THROUGH WILL SEE LINGERING RAIN
WITH IT CHANGING OVER TO LIGHT SNOW AND SLEET TOWARDS DAYBREAK
BEFORE COMING TO AN END. AS FOR WINDS...TO PERSIST FROM THE
SOUTH...THEN GRADUALLY VEER TO THE SOUTHWEST...THEN TO THE NORTH
BEHIND THE FRONT. WILL SEE GUSTS TO NEAR 25KTS DURING THE DAY ON
MONDAY...BEFORE DIMINISHING AS RIDGE BUILDS IN AND CIGS SCATTER OUT
AROUND 23Z MON.
BYRD
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...FLOOD WATCH THROUGH LATE TONIGHT FOR AUDRAIN MO-BOONE MO-
CALLAWAY MO-COLE MO-KNOX MO-LEWIS MO-LINCOLN MO-MARION MO-
MONITEAU MO-MONROE MO-MONTGOMERY MO-PIKE MO-RALLS MO-SHELBY
MO.
DENSE FOG ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR AUDRAIN MO-
KNOX MO-LEWIS MO-MARION MO-MONROE MO-PIKE MO-RALLS MO-
SHELBY MO.
IL...FLOOD WATCH THROUGH LATE TONIGHT FOR ADAMS IL-BROWN IL-CALHOUN
IL-GREENE IL-PIKE IL.
DENSE FOG ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR ADAMS IL-BROWN
IL-PIKE IL.
&&
WFO LSXHAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE ST LOUIS MO 407 PM CST SUN FEB 27 2011 ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027- 034>036-041-042-047>052-059>065-072>075-084-085-099-281200- 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- 407 PM CST SUN FEB 27 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EASTERN AND CENTRAL MISSOURI AS WELL AS WEST CENTRAL AND SOUTHWEST ILLINOIS. .DAY ONE...TONIGHT AN OUTBREAK OF SEVERE THUNDERSTORMS IS EXPECTED MAINLY FOR THIS EVENING...ALTHOUGH IT MAY CONTINUE PAST MIDNIGHT FOR SOME AREAS. FOR AREAS MAINLY NORTH OF INTERSTATE 70...LARGE HAIL IS EXPECTED TO BE THE MAIN SEVERE THREAT. FOR AREAS ALONG AND SOUTH OF THE INTERSTATE 70 CORRIDOR...THE SEVERE THREATS WILL INCLUDE LARGE HAIL...DAMAGING WINDS...AND POSSIBLY A FEW TORNADOES. FOR FURTHER INFORMATION ON CONVECTIVE WATCHES...PLEASE REFER TO THE LATEST STORM PREDICTION CENTER WATCH PRODUCTS. THE COMBINATION OF SATURATED GROUND OR PARTIALLY FROZEN GROUND WITH EXISTING AND MELTING SNOW COVER AND A PERSISTENT AREA OF SHOWERS AND THUNDERSTORMS WILL RESULT IN AN INCREASED RISK FOR FLOODING FROM STREAMS AND SMALL RIVERS TONIGHT FOR AREAS IN NORTHEAST AND CENTRAL MISSOURI AND WEST CENTRAL ILLINOIS. PLEASE SEE THE FLOOD WATCH PRODUCT FOR FURTHER INFORMATION. WIDESPREAD DENSE FOG...REDUCING VISIBILITIES TO ONE QUARTER MILE OR LESS AT TIMES...IS EXPECTED ACROSS PARTS OF CENTRAL AND NORTHEAST MISSOURI AND WEST CENTRAL ILLINOIS THROUGH THIS EVENING WITH IMPROVEMENT EXPECTED BY MIDNIGHT. PLEASE SEE THE DENSE FOG ADVISORY PRODUCT FOR FURTHER INFORMATION. ENOUGH COLD AIR WILL SPILL IN BEHIND THE FRONT TO CHANGE THE PRECIPITATION OVER TO SLEET AND SNOW AFTER MIDNIGHT FOR PARTS OF NORTHEAST MISSOURI AND WEST CENTRAL ILLINOIS. MINOR ACCUMULATIONS OF SNOW AND SLEET ARE POSSIBLE. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY SNOW AND SOME SLEET IS EXPECTED FOR MONDAY MORNING FOR AREAS MAINLY TO THE NORTH AND EAST OF SAINT LOUIS. SNOW ACCUMULATIONS ARE EXPECTED TO BE LESS THAN AN INCH. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS LIKELY ANYTIME FROM THIS AFTERNOON THROUGH TONIGHT. TES
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
611 PM CST SUN FEB 27 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0610 PM HAIL SHELBYVILLE 39.81N 92.04W
02/27/2011 E0.25 INCH SHELBY MO LAW ENFORCEMENT
&&
TRUETTPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
614 PM CST SUN FEB 27 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0613 PM HAIL 4 S MADISON 39.42N 92.21W
02/27/2011 E0.70 INCH MONROE MO TRAINED SPOTTER
ON HIGHWAY 151
&&
TRUETTPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
618 PM CST SUN FEB 27 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0612 PM HAIL MADISON 39.47N 92.21W
02/27/2011 E0.50 INCH MONROE MO TRAINED SPOTTER
ONE-QUARTER TO ONE-HALF INCH HAIL
&&
TRUETTPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
624 PM CST SUN FEB 27 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0623 PM HAIL PALMYRA 39.43N 90.00W
02/27/2011 E0.25 INCH MACOUPIN IL TRAINED SPOTTER
&&
TRUETTPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
625 PM CST SUN FEB 27 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0623 PM HAIL PALMYRA 39.80N 91.52W
02/27/2011 E0.75 INCH MARION MO LAW ENFORCEMENT
&&
TRUETTPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
626 PM CST SUN FEB 27 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0620 PM HAIL PALMYRA 39.80N 91.52W
02/27/2011 E0.50 INCH MARION MO TRAINED SPOTTER
&&
TESThe St Louis radar (KLSX), 150 km away, was scanning. The volume nearest the first event began at 00:28 UTC.
16 thunderstorm wind, 10 tornado, 4 hail. Local standard time, as filed.
A wide swath of three quarter to one inch hail was reported from Quincy through the Camp Point area to between Golden and Clayton.
Thunderstorm winds blew down several large trees along Illinois Route 96 between New Canton and Rockport. One of the trees landed on a house causing moderate damage.
It was determined that an EF1 tornado cut a 100 yard wide, over 3 mile long path through Granite City. The tornado first touched down at approximately 11:35 PM near the intersection of Illinois Route 3 and Rock Road. There, a large storage facility lost much of its roof. The tornado rapidly moved eastward at nearly 60 mph, causing significant tree and roof damage in its path. The tornado reached Maryville Road at around 11:38 PM where it dissipated.
Thunderstorm winds blew down part of a fence and bent a flag pole in half in Cahokia.
The tornado touched down between Edwardsville and Glen Carbon near the intersection of Ginger Creek Drive and Illinois Route 157. There were several cedar trees uprooted at this location. The tornado continued east-northeast through the Ginger Creek Subdivision to the intersection of Center Grove Road and Illinois Route 159. This is where a metal industrial building sustained roof and siding damage. The tornado also crossed the intersection of Center Grove Road and Troy Road where a few signs of local businesses were damaged and a Home Depot sustained some damage to small preconstructed sheds sitting outside. The tornado continued east-northeast to near the intersection of Gerber Road and Governors Parkway where several houses sustained minor roof and siding damage. The tornado dissipated just beyond this location. The path length of this tornado was 2.4 miles long. Most of the damage along the path was rated EF0 with the maximum intensity rated EF1 for some tree damage and the industrial building damage. The maximum path width was 150 yards.
Thunderstorm winds blew down several trees, numerous tree limbs and tore a 16 foot by 24 foot section of a roof off of Copper Creek Christian Church. A pavilion at Drost Park was picked up and dropped about 10 feet away from its original location.
The tornado formed just west of Interstate 55 near Mick Road approximately 2 miles north of the Interstate 55/70/255 interchange where a few power poles were knocked over. The tornado crossed Interstate 55 and produced minor tree damage. It continued east-northeast where it produced roof and siding damage to a couple of homes. One home had part of the roof decking on the south side of the house removed while another had a flag pole located well to the north of the structure bent over almost to ground level. This pole was pointing south. Further along the path, a barn was destroyed along Staunton Road with debris strewn several hundred yards across the road into an open field. The tornado continued east-northeast until it snapped several mature pine trees off several feet above the ground along Nealy Lane. The tornado dissipated before reaching Illinois Route 4. The path length was 2 miles. The tornado had a maximum width of 50 yards and maximum intensity of EF1 for the destroyed barn and the snapped pine trees.
It was determined that a tornado touched down on Weathervane Road on the west side of Troy at approximately 11:45 PM. It was there that the tornado was at its strongest, an EF2, as it completely removed the roof from a well constructed home. One occupant received a serious head laceration and was treated at a local hospital. The tornado moved eastward at 60 mph, with a damage swath of 100 to 200 yards wide. Numerous trees, power lines, and roofs sustained minor to moderate damage along its path. The tornado continued to near the intersection of North Dewey Street and East Market Street, where it lifted at approximately 11:48 PM. The path length was 2.7 miles long.
Thunderstorm winds blew over a semi on Illinois Route 177 east of Mascoutah. No injuries were reported.
Thunderstorm winds blew the metal roof off of a shed and part of the roof off of a grain silo.
Thunderstorm winds blew down several power lines, tree limbs and signs througout town.
Thunderstorm winds caused a barn to collapse on a hog farm. Four hogs were killed.
A tornado touched down approximately 2.5 miles north of Pocahontas at a farm and residence along File Avenue. A concentrated area of extensive tree damage was found next to the residence. Every hardwood and softwood tree in this area was snapped at the trunk. Tree tops were thrown 30 to 50 yards. Several trees were also uprooted. The house sustained shingle damage and two supporting posts on the house were blown out. A granary was destroyed with debris thrown between 50 and 100 yards. A large metal storage shed lost its roof and two walls were blown out with debris scattered between 1/4 and 1/2 mile. The tornado skipped east, hitting another farmstead on Shawnee Road, causing damage to a silo and roof. The debris was tossed to the north over 300 yards. The maximum damage was rated EF1 with a maximum wind speed around 100 mph. The total length of the tornado was 2.7 miles with a maximum width of 50 yards.
The tornado formed just to the southwest of Okawville. The tornado moved across the south side of town and damaged the local grain elevator, produced some minor roof and exterior damage to houses along the south side of East Schumacher Street. The Emmanuel Lutheran School also sustained some minor roof damage. The tornado continued to the east where it produced some additional damage and snapped an 8-10 inch diameter tree trunk approximately 6 feet off the ground. The tornado continued east until it damaged a house on Hummingbird Road. This house suffered an unknown amount of roof damage because it was in the process of being repaired. There was also minor tree damage and an outbuilding that was destroyed with the debris scattered several hundred yards to the northeast. The tornado lifted just to the east of this location. Path length was 2.8 miles with a maximum width of 50 yards and rated EF0.
The tornado touched down approximately 6 miles east of Okawville on Illinois Route 177 near the Kuhl Lumber and Pallet Company. Minor roof and siding damage occurred to an ongoing construction project at the saw mill. A few trees along a tree line to the east of the complex were topped. The tornado continued east where it struck a farmstead causing considerable damage. A 48 by 96 foot machine shed was completely destroyed with much of the debris scattered up to almost one mile to the east. Another building was lost at this location as well as a grain bin. Two other barns sustained damage with one being pushed off the foundation by several feet. The debris from the machine shed impacted the house, garage and workshop with several missiles not only in the ground but also into other structures. The home sustained several broken windows from flying debris. The roof of the home had at least five rafters damaged when an unknown heavy object hit the roof, but was blown away during the storm. The tornado continued to the east and dissipated approximately one mile west of New Minden. The path length was 2.3 miles with a maximum intensity of EF2 due to the damage at the farmstead. Maximum damage width was 100 yards.
Thunderstorm winds blew down a barn and snapped several power poles.
Thunderstorm winds blew down a couple of ham radio antennas.
Thunderstorm winds blew down a large tree onto Zion Church Road, southeast of Walsh.
A tornado touched down in Confidence, Illinois approximately 8 miles southwest of St. Elmo or 9.5 miles east-southeast of Vandalia. The tornado touched down near the intersection of County Road 1750E and County Road 1275N. In this location it damaged a residence, trees, and outbuildings. A convergent pattern was found in the debris. The tornado then continued east northeast and damaged several residences and farm buildings along County Road 1275N. One residence was shifted 22 feet off the foundation and another was shifted 6 feet off the foundation. Lumber from the roof was driven into the siding and into the foundation at a third residence. The tornado then skipped through a wooded area north of County Road 1275N before lifting west of Illinois Route 185. The maximum damage was rated EF2 with a maximum wind speed around 120 mph. The total length of this tornado was approximately 1.3 miles with a maximum width of 90 yards.
Thunderstorm winds blew down numerous tree limbs and several power lines.
A tornado briefly touched down approximately 1 mile southeast of St. Elmo at a farm building located a tenth of a mile south of Interstate 70 and two tenths of a mile north of County Road 1900N along County Road 2250E. The south facing wall of a large metal farm storage building was blown out with debris scattered over one half mile into an adjacent field. Several 2x4s were driven several feet into the ground. A billboard just south of the farm building supported by 16 wooden posts, each 5 to 10 inches in diameter. All of these posts were snapped but there was no damage to the power poles directly across the road. Since the billboard was found on the road directly in front of the posts rather than farther downstream, it appears that straight line winds caused damage to the billboard while the tornado was responsible for damage to the farm building. The maximum damage was rated EF1 with a maximum wind speed around 95 mph. The total length of this tornado was approximately two tenths of a mile with a maximum width of 10 yards.
A tornado briefly touched down near the Fayette and Effingham county line approximately two tenths of a mile south of County Road 1800N. Two large farm buildings were destroyed and debris was thrown 1 mile to the east into Effingham County. Other farm buildings also sustained damage. There were four spots on the property with evidence that heavy debris, including a cinderblock, was thrown a substantial distance to the northwest. Several 2x4s were driven several feet into the ground. The tornado did not go into Effingham county. The maximum damage was rated EF2 with a maximum wind speed around 115 mph. The total length of this tornado was a tenth of a mile with a maximum width of 50 yards.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Illinois in 2011Every state in 2011This day in weather historyThe tornado archive for Illinois, 2011Warnings in Illinois, February 2011
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: 283703, 283704, 283706, 287709, 284548, 287294, 284639, 287705, 286532, 287704, 286537, 284640, 287706, 287710, 287715, 287711, 287712, 287714, 284641, 287713, 286541, 286550, 287716, 287718, 287725, 287723, 284642, 287724, 284646, 284645.