Alert archive / Missouri / Tornado Warnings in 2011

Tornado Warning 66, NWS St. Louis, MO

May 22, 20115 counties in Missouri

NWS St. Louis, MO issued this tornado warning at May 22, 2011, 6:28 PM CDT for 5 counties in Missouri. It was in force for 47 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: May 22, 2011, 6:28 PM CDT (23:28 UTC)
Expired: May 22, 2011, 7:15 PM CDT
In force: 47 min
Issued by: NWS St. Louis, MO
Area: Storm-based polygon

Counties Franklin County, MO, Gasconade County, MO, Montgomery County, MO, Osage County, MO, Warren County, MO

The radar

The St Louis radar (KLSX), 82 km from the middle of the area, began a volume at 23:30 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.

What was reported inside it

Time	Report	Where	Remark
May 22, 6:51 PM CDT	HAIL 0.7	Gasconade, MO

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this tornado warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
May 22, 12:51 PM CDT	Tornado Watch	SPC	10 hr

The nearest sounding before it

Springfield, MO (KSGF), launched 12:00Z, 11.5 hours before the alert went out and 274 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: 2645 J/kg
Mixed-layer CIN: -122 J/kg
Mixed-layer LCL: 678 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: 424 m²/s²
0-3 km storm-relative helicity: 422 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 16.9

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

051 
WFUS53 KLSX 222328
TORLSX
MOC071-073-139-151-219-230015-
/O.NEW.KLSX.TO.W.0066.110522T2328Z-110523T0015Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
628 PM CDT SUN MAY 22 2011

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* TORNADO WARNING FOR...
  NORTHWESTERN FRANKLIN COUNTY IN EAST CENTRAL MISSOURI...
  GASCONADE COUNTY IN EAST CENTRAL MISSOURI...
  EXTREME SOUTHERN MONTGOMERY COUNTY IN EAST CENTRAL MISSOURI...
  NORTHEASTERN OSAGE COUNTY IN CENTRAL MISSOURI...
  WEST CENTRAL WARREN COUNTY IN EAST CENTRAL MISSOURI...

* UNTIL 715 PM CDT

* AT 626 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THIS DANGEROUS
  STORM WAS LOCATED NEAR LINN...AND MOVING EAST AT 30 MPH.

* LOCATIONS IMPACTED INCLUDE...
  HERMANN...NEW HAVEN...MORRISON...GASCONADE...BAY...SWISS...
  RHINELAND...MCKITTRICK AND BERGER.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR
OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT
YOURSELF FROM FLYING DEBRIS.

&&

LAT...LON 3871 9167 3870 9166 3872 9164 3883 9133
      3859 9120 3843 9187 3859 9195
TIME...MOT...LOC 2328Z 248DEG 27KT 3855 9180

$$

CARNEY

2 follow-up statements

891 
WWUS53 KLSX 222345
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
645 PM CDT SUN MAY 22 2011

MOC071-073-139-151-219-230015-
/O.CON.KLSX.TO.W.0066.000000T0000Z-110523T0015Z/
FRANKLIN MO-GASCONADE MO-MONTGOMERY MO-OSAGE MO-WARREN MO-
645 PM CDT SUN MAY 22 2011

...A TORNADO WARNING REMAINS IN EFFECT FOR WEST CENTRAL WARREN...
NORTHEASTERN OSAGE...EXTREME SOUTHERN MONTGOMERY...GASCONADE AND
NORTHWESTERN FRANKLIN COUNTIES UNTIL 715 PM CDT...

AT 639 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS DANGEROUS
STORM WAS LOCATED 8 MILES SOUTHEAST OF CHAMOIS...OR 10 MILES
NORTHEAST OF LINN...MOVING EAST AT 30 MPH.

LOCATIONS IMPACTED INCLUDE...
  HERMANN...NEW HAVEN...MORRISON...GASCONADE...BAY...SWISS...
  RHINELAND...MCKITTRICK AND BERGER.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR
OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT
YOURSELF FROM FLYING DEBRIS.

TO REPORT SEVERE WEATHER...CONTACT YOUR NEAREST LAW ENFORCEMENT
AGENCY. THEY WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE
IN ST LOUIS.

&&

LAT...LON 3871 9168 3870 9166 3872 9164 3883 9133
      3859 9120 3851 9175 3864 9183
TIME...MOT...LOC 2345Z 248DEG 27KT 3860 9165

$$

CARNEY

036 
WWUS53 KLSX 230000
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
700 PM CDT SUN MAY 22 2011

MOC071-073-139-151-219-230015-
/O.CON.KLSX.TO.W.0066.000000T0000Z-110523T0015Z/
FRANKLIN MO-GASCONADE MO-MONTGOMERY MO-OSAGE MO-WARREN MO-
700 PM CDT SUN MAY 22 2011

...A TORNADO WARNING REMAINS IN EFFECT FOR WEST CENTRAL WARREN...
NORTHEASTERN OSAGE...EXTREME SOUTHERN MONTGOMERY...NORTHERN GASCONADE
AND NORTHWESTERN FRANKLIN COUNTIES UNTIL 715 PM CDT...

AT 659 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS DANGEROUS
STORM WAS LOCATED 7 MILES WEST OF HERMANN...MOVING EAST AT 30 MPH.

LOCATIONS IMPACTED INCLUDE...
  HERMANN...NEW HAVEN...RHINELAND...MCKITTRICK AND BERGER.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW. MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
STURDY BUILDING. AVOID WINDOWS. IF IN A MOBILE HOME...A VEHICLE OR
OUTDOORS...MOVE TO THE CLOSEST SUBSTANTIAL SHELTER AND PROTECT
YOURSELF FROM FLYING DEBRIS.

TO REPORT SEVERE WEATHER...CONTACT YOUR NEAREST LAW ENFORCEMENT
AGENCY. THEY WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE
IN ST LOUIS.

&&

LAT...LON 3870 9167 3872 9164 3883 9133 3859 9120
      3858 9169 3865 9171
TIME...MOT...LOC 0001Z 248DEG 27KT 3868 9155

$$

CARNEY

What forecasters said that day

The local office's own words before this tornado 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 tornado warning went out at May 22, 6:17 PM CDT, 11 minutes earlier.

Area forecast discussion, May 22, 6:17 PM CDT, 11 minutes before

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
617 PM CDT SUN MAY 22 2011

.DISCUSSION...
/355 PM CDT SUN MAY 22 2011/

MAIN CONCERN THROUGH MID WEEK WITH BE AN ONGOING POTENTIAL FOR
SEVERE THUNDERSTORMS AND WIDESPREAD...POSSIBLY HEAVY RAINFALL.

SCATTERED THUNDERSTORMS HAVE DEVELOPED OVER EASTERN MO INTO
CENTRAL ILLINOIS ALONG A GRAVITY WAVE WELL AHEAD OF SURFACE COLD
FRONT NOW EXTENDING FROM NORTH CENTRAL MO SOUTHWESTWARD INTO
SOUTHEAST KANSAS. DEWPOINTS WELL INTO THE 60S TO AROUND 70 HAVE
ADVECTED INTO THE REGION UNDER VERY STEEP LAPSE RATES WHICH HAVE
RESULTED IN MLCAPES BETWEEN 3000-4000 J/KG. LARGE SCALE ASCENT
WILL LIKELY INCREASE SLIGHTLY INTO THE EVENING AS SUBTLE SHORTWAVE
CURRENTLY OVER CENTRAL PLAINS MOVES INTO THE AREA THIS EVENING.
THIS SHOULD CAUSE AN INCREASE IN THE COVERAGE OF STORMS OVER CWA
THIS EVENING...BOTH ALONG AND AHEAD OF THE COLD FRONT. DEEP LAYER
SHEAR WILL REMAIN FAVORABLE FOR SUPERCELLS THROUGH THE EVENING
WITH VERY LARGE HAIL POSSIBLE GIVEN THE VERY STEEP LAPSE RATES.
IN ADDITION...THE LOW LEVEL SHEAR ALONG WITH THE VERY UNSTABLE
ATMOSPHERE WILL CONTINUE TO KEEP A TORNADO THREAT INCLUDING
POSSIBLY A STRONG TORNADO OR TWO THROUGH THE EVENING.

THE FRONT WILL BECOME EAST TO WEST ORIENTED UNDER ZONAL FLOW THE
NEXT FEW DAYS AS THE UPPER LOW CURRENTLY OVER THE MIDWEST LIFTS
EASTWARD BY TOMORROW. THERE WILL BE A SERIES OF SHORTWAVES MOVE
ALONG THE FRONT THE NEXT FEW DAYS WHICH SHOULD GENERATE SEVERAL
ROUNDS OF THUNDERSTORMS ACROSS THE REGION. IT WILL BE DIFFICULT TO
PIN DOWN THE SPECIFICS AS MODELS ARE SLIGHTLY DIFFERENT IN THE
TIMING OF THE SHORTWAVES AND THE LOCATION OF THE EFFECTIVE FRONT
WILL BE DEPENDENT ON THE OUTFLOW FROM POTENTIAL MCS...BUT THERE
WILL CONTINUE TO BE ENOUGH INSTABILITY AND SHEAR FOR ROUNDS OF
SEVERE THUNDERSTORMS THROUGH WEDNESDAY. IN ADDITION...THERE WILL
BE ABUNDANT MOISTURE FOR THE STORMS TO PRODUCE HEAVY RAINFALL.
FLASH FLOODING WILL BE POSSIBLE WHERE THERE IS ANY TRAINING. DO
NOT HAVE ENOUGH CONFIDENCE TO ISSUE ANY KIND OF FLOOD WATCH AT
THIS POINT...SO WILL GO AHEAD AND MENTION THIS POTENTIAL IN A
HYDROLOGICAL OUTLOOK. RAIN WILL LIKELY END LATER IN THE WEEK WHEN
CLOSED LOW FINALLY MOVES ACROSS THE AREA AND PUSHES FRONT SOUTH.

BRITT

&&

.AVIATION...
/613 PM CDT SUN MAY 22 2011/

ONGOING STORMS ACROSS PARTS OF MISSOURI AND ILLINOIS WILL PERSIST
FOR THE NEXT FEW HOURS AND POSSIBLY GROW UPSCALE INTO ONE OR MORE
LINES. ONCE THE STORMS MOVE THROUGH...VFR CONDITIONS ARE EXPECTED
FOR THE REST OF THE PERIOD. THUNDERSTORMS ARE POSSIBLE AGAIN
TOMORROW AFTN BUT CONFIDENCE IN TIMING AND LOCATION IS TOO LOW FOR
ANYTHING MORE THAN A CB GROUP ATTM.

SPECIFICS FOR KSTL...ONGOING STORMS WILL PERSIST FOR THE NEXT FEW
HOURS AND POSSIBLY GROW UPSCALE INTO ONE OR MORE LINES. ONCE THE
STORMS MOVE THROUGH KSTL...VFR CONDITIONS ARE EXPECTED FOR THE
REST OF THE PD. ALTHOUGH THUNDERSTORMS ARE POSSIBLE AGAIN TOMORROW
AFTN...CONFIDENCE IN TIMING AND LOCATION IS TOO LOW FOR ANYTHING
MORE THAN A CB GROUP ATTM.

KANOFSKY

&&

.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&

WFO LSX

Hazardous weather outlook, May 22, 4:20 PM CDT, 2 hours 8 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE ST LOUIS MO
420 PM CDT SUN MAY 22 2011

ILZ058>060-064-065-069-070-074-079-095>102-MOZ018-019-026-027-
034>036-041-042-047>052-059>065-072>075-084-085-099-231145-
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-
420 PM CDT SUN MAY 22 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 LIKELY THROUGH THIS EVENING
OVER MUCH THE REGION. THE MOST INTENSE STORMS WILL BE CAPABLE OF
PRODUCING ONE OR TWO STRONG TORNADOES...GOLFBALL OR LARGER SIZE
HAIL AND DAMAGING WIND GUSTS IN EXCESS OF 60 MPH.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY

THUNDERSTORMS WILL BE LIKELY OVER THE AREA THROUGH WEDNESDAY.
THERE IS THE POTENTIAL FOR SEVERAL ROUNDS OF SEVERE THUNDERSTORMS
DURING THIS PERIOD. THESE THUNDERSTORMS WILL ALSO PRODUCE
WIDESPREAD RAINFALL WHICH MAY BE HEAVY AT TIMES ACROSS THE REGION.
THIS MAY CAUSE RISES ON AREA STREAMS...CREEKS AND AREA RIVERS.

THERE IS ALSO A CHANCE OF THUNDERSTORMS OVER THE REGION ON
WEDNESDAY NIGHT AND THURSDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS LIKELY THROUGH TONIGHT.

BRITT

In the hours before

Local storm report, May 22, 6:05 PM CDT, 23 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
605 PM CDT SUN MAY 22 2011

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

0605 PM     HAIL             8 N COLUMBIA            39.07N  92.33W
05/22/2011  E1.00 INCH       BOONE              MO   TRAINED SPOTTER

&&

GOSSELIN

Local storm report, May 22, 6:06 PM CDT, 22 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
606 PM CDT SUN MAY 22 2011

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

0605 PM     TSTM WND GST     HALLSVILLE              39.12N  92.22W
05/22/2011  E65 MPH          BOONE              MO   LAW ENFORCEMENT

&&

MILLER

Local storm report, May 22, 6:07 PM CDT, 21 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
607 PM CDT SUN MAY 22 2011

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

0606 PM     HAIL             HALLSVILLE              39.12N  92.22W
05/22/2011  E0.70 INCH       BOONE              MO   TRAINED SPOTTER

&&

MILLER

Local storm report, May 22, 6:15 PM CDT, 13 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
615 PM CDT SUN MAY 22 2011

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

0614 PM     WALL CLOUD       LOOSE CREEK             38.51N  91.96W
05/22/2011                   OSAGE              MO   TRAINED SPOTTER

            SEES ROTATION LOOKING SW

&&

MILLER

Local storm report, May 22, 6:21 PM CDT, 7 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
621 PM CDT SUN MAY 22 2011

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

0605 PM     HAIL             2 NE HALLSVILLE         39.14N  92.19W
05/22/2011  E0.88 INCH       BOONE              MO   LAW ENFORCEMENT

&&

MILLER

Local storm report, May 22, 6:23 PM CDT, 5 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST LOUIS MO
623 PM CDT SUN MAY 22 2011

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

0610 PM     HAIL             4 NE BURTON             39.94N  91.20W
05/22/2011  M0.25 INCH       ADAMS              IL   ASOS

&&

KANOFSKY

The office that day

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

Issued	Product	Office	Counties	Lasted
May 21, 9:26 PM CDT	River Flood Warning	LSX	Saint Charles	55 days
May 21, 10:55 PM CDT	River Flood Warning	LSX	Saint Charles, Saint Louis	3 days
May 22, 3:15 PM CDT	Severe Thunderstorm Warning	LSX	Franklin, Gasconade, Montgomery, Osage, Warren	45 min
May 22, 3:59 PM CDT	Severe Thunderstorm Warning	LSX	Franklin, Gasconade, Warren	46 min
May 22, 4:15 PM CDT	Severe Thunderstorm Warning	LSX	Callaway, Gasconade, Montgomery, Osage	45 min
May 22, 4:32 PM CDT	Severe Thunderstorm Warning	LSX	Saint Charles, Warren	58 min
May 22, 4:35 PM CDT	Severe Thunderstorm Warning	LSX	Lincoln, Montgomery, Warren	55 min
May 22, 4:45 PM CDT	Severe Thunderstorm Warning	LSX	Warren	45 min
May 22, 5:02 PM CDT	Tornado Warning	LSX	Franklin, Warren	45 min
May 22, 5:15 PM CDT	Severe Thunderstorm Warning	LSX	Boone	45 min
May 22, 5:20 PM CDT	Severe Thunderstorm Warning	LSX	Callaway, Cole, Moniteau, Osage	40 min
May 22, 5:21 PM CDT	Severe Thunderstorm Warning	LSX	Callaway, Montgomery	54 min
May 22, 5:27 PM CDT	Tornado Warning	LSX	Callaway, Montgomery	48 min
May 22, 5:37 PM CDT	Tornado Warning	LSX	Saint Charles	38 min
May 22, 5:54 PM CDT	Severe Thunderstorm Warning	LSX	Callaway, Cole, Gasconade, Montgomery, Osage	51 min
May 22, 5:57 PM CDT	Severe Thunderstorm Warning	LSX	Audrain, Boone, Callaway, Montgomery	48 min
May 22, 6:08 PM CDT	Severe Thunderstorm Warning	LSX	Callaway, Gasconade, Montgomery, Osage, Warren	36 min
May 22, 6:12 PM CDT	Severe Thunderstorm Warning	LSX	Lincoln, Montgomery, Pike	48 min
May 22, 6:12 PM CDT	Tornado Warning	LSX	Audrain, Callaway, Montgomery, Pike, Ralls	33 min
May 22, 6:23 PM CDT	Tornado Warning	LSX	Callaway, Montgomery	12 min
May 22, 6:47 PM CDT	Severe Thunderstorm Warning	LSX	Audrain, Callaway, Montgomery, Pike	58 min
May 22, 6:54 PM CDT	Severe Thunderstorm Warning	LSX	Lincoln, Pike	39 min
May 22, 6:58 PM CDT	Severe Thunderstorm Warning	LSX	Callaway, Cole, Franklin, Gasconade, Montgomery, Osage and 1 more	47 min

Nearby

Tornado Warnings in Missouri, 2011 Every tornado warning in 2011 Tornadoes in 2011

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.