Alert archive / Missouri / Tornado Warnings in 2010

Tornado Warning 48, NWS St. Louis, MO

June 21, 2010Knox County, Missouri

NWS St. Louis, MO issued this tornado warning at Jun 21, 2010, 8:57 PM CDT for Knox County, Missouri. It was in force for 48 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Jun 21, 2010, 8:57 PM CDT (01:57 UTC)
Expired: Jun 21, 2010, 9:45 PM CDT
In force: 48 min
Issued by: NWS St. Louis, MO
Area: Storm-based polygon

County Knox County, MO

The radar

The Quad Cities radar (KDVN), 204 km from the middle of the area, began a volume at 01:59 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.

The watch it was issued in

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

Issued	Product	Office	Lasted
Jun 21, 4:36 PM CDT	Tornado Watch	SPC	5 hr

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 2.0 hours before the alert went out and 209 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: 2621 J/kg
Mixed-layer CIN: -18 J/kg
Mixed-layer LCL: 930 m above ground
0-6 km bulk shear: 40 kt
0-1 km storm-relative helicity: 102 m²/s²
0-3 km storm-relative helicity: 154 m²/s²
Significant tornado parameter: 1.5
Supercell composite: 7.6

Open this sounding in Storm Lab

The text

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

079 
WFUS53 KLSX 220157
TORLSX
MOC103-220245-
/O.NEW.KLSX.TO.W.0048.100622T0157Z-100622T0245Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
857 PM CDT MON JUN 21 2010

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* TORNADO WARNING FOR...
  NORTHERN KNOX COUNTY IN NORTHEAST MISSOURI...

* UNTIL 945 PM CDT

* AT 853 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THIS DANGEROUS
  STORM WAS LOCATED NEAR GREENSBURG...OR 12 MILES NORTHWEST OF   
  EDINA...AND MOVING SOUTHEAST AT 25 MPH. THIS STORM HAS A HISTORY 
  OF PRODUCING LARGE DANGEROUS HAIL TO GOLF BALL SIZE.

* LOCATIONS IMPACTED INCLUDE...
  EDINA...GREENSBURG...HURDLAND AND BARING.

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.

TORNADOES ARE DIFFICULT TO SEE AND CONFIRM AT NIGHT. TAKE COVER NOW.

&&

LAT...LON 4019 9196 4012 9232 4030 9236 4031 9233
      4031 9217
TIME...MOT...LOC 0156Z 306DEG 23KT 4029 9229

$$

TES

1 follow-up statement

581 
WWUS53 KLSX 220240
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
940 PM CDT MON JUN 21 2010

MOC103-220247-
/O.EXP.KLSX.TO.W.0048.000000T0000Z-100622T0245Z/
KNOX MO-
940 PM CDT MON JUN 21 2010

...THE TORNADO WARNING FOR NORTHERN KNOX COUNTY WILL EXPIRE AT 945 PM
CDT...

THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE WARNED 
AREA...HOWEVER A TORNADO WARNING REMAINS IN EFFECT FOR NORTHEASTERN 
KNOX COUNTY AND NORTHWESTERN LEWIS COUNTY UNTIL 1000 PM CDT.

ADDITIONAL STRONG THUNDERSTORMS ARE STILL POSSIBLE...AND A TORNADO 
WATCH REMAINS IN EFFECT UNTIL 1000 PM CDT.

LAT...LON 4019 9196 4012 9232 4030 9236 4031 9233
      4031 9217
TIME...MOT...LOC 0237Z 306DEG 23KT 4014 9201

$$

KANOFSKY

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 21, 9:15 PM CDT	Tornado Warning	LSX	Knox, Lewis	45 min
Jun 21, 9:52 PM CDT	Tornado Warning	LSX	Lewis	38 min
Jun 21, 10:27 PM CDT	Tornado Warning	LSX	Lewis	22 min
Jun 22, 3:23 AM CDT	River Flood Warning	LSX	Lewis	3 days
Jun 22, 9:40 AM CDT	Severe Thunderstorm Warning	LSX	Lewis	54 min

Nearby

Tornado Warnings in Missouri, 2010 Every tornado warning in 2010 Tornadoes in 2010

Sources

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