Alert archive / Missouri / Tornado Watches in 2013

Tornado Watch 263

May 31, 201314 counties in Illinois; 15 counties in Missouri

The Storm Prediction Center issued this tornado watch at May 31, 2013, 5:45 PM CDT for 14 counties in Illinois; 15 counties in Missouri. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
May 31, 2013, 5:45 PM CDT (22:45 UTC)
Expired
May 31, 2013, 10:00 PM CDT
In force
4 hr
Issued by
the Storm Prediction Center
Largest hail expected
1.5 in
Strongest gust expected
60 kt
All 29 counties

Bond County, IL, Calhoun County, IL, Clinton County, IL, Fayette County, IL, Greene County, IL, Jersey County, IL, Macoupin County, IL, Madison County, IL, Marion County, IL, Monroe County, IL, Montgomery County, IL, Randolph County, IL, Saint Clair County, IL, Washington County, IL, Audrain County, MO, City of Saint Louis, MO, Crawford County, MO, Franklin County, MO, Gasconade County, MO, Jefferson County, MO, Lincoln County, MO, Montgomery County, MO, Pike County, MO, Saint Charles County, MO, Saint Francois County, MO, Saint Louis County, MO, Sainte Genevieve County, MO, Warren County, MO, Washington County, MO

The radar

The St Louis radar (KLSX), 26 km from the middle of the area, began a volume at 22:45 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 SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
40%
One or more EF2 to EF5 tornadoes
20%
Ten or more severe wind reports
60%
One or more gusts of 65 knots or more
10%
Ten or more severe hail reports
30%
One or more hailstones of 2 inches or more
10%
Six or more combined severe hail and wind reports
90%

Warnings issued inside it

27 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
May 31, 5:56 PM CDTSevere Thunderstorm WarningLSXCallaway, Lincoln, Montgomery, Warren49 min
May 31, 6:05 PM CDTTornado WarningLSXCallaway, Montgomery, Warren25 min
May 31, 6:09 PM CDTSevere Thunderstorm WarningLSXGasconade, Osage51 min
May 31, 6:26 PM CDTTornado Warning Tornado observedLSXLincoln, Montgomery, Warren34 min
May 31, 6:47 PM CDTSevere Thunderstorm WarningLSXFranklin, Gasconade, Saint Charles, Warren43 min
May 31, 6:56 PM CDTSevere Thunderstorm WarningLSXLincoln, Saint Charles, Warren34 min
May 31, 6:58 PM CDTFlash Flood WarningLSXCole, Gasconade, Moniteau, Osage6 hr
May 31, 6:58 PM CDTSevere Thunderstorm WarningLSXGasconade, Montgomery, Osage32 min
May 31, 7:16 PM CDTTornado WarningLSXLincoln29 min
May 31, 7:26 PM CDTTornado WarningLSXFranklin34 min
May 31, 7:30 PM CDTSevere Thunderstorm WarningLSXCalhoun, Jersey, Madison45 min
May 31, 7:48 PM CDTTornado WarningLSXSaint Charles, Saint Louis27 min
May 31, 7:59 PM CDTTornado WarningLSXMonroe31 min
May 31, 8:08 PM CDTTornado Warning Tornado observedLSXMadison37 min
May 31, 8:12 PM CDTSevere Thunderstorm WarningLSXGreene, Jersey, Macoupin, Madison, Monroe, Saint Clair48 min
May 31, 8:26 PM CDTTornado WarningLSXMonroe, Saint Clair34 min
May 31, 8:31 PM CDTTornado WarningLSXGreene, Jersey, Macoupin29 min
May 31, 8:33 PM CDTTornado WarningLSXBond, Madison27 min
May 31, 8:43 PM CDTFlash Flood WarningLSXFranklin, Saint Charles, Saint Louis, Warren, City of Saint Louis6 hr
May 31, 8:50 PM CDTSevere Thunderstorm WarningLSXBond, Clinton, Fayette, Macoupin, Madison, Montgomery and 2 more55 min
May 31, 8:50 PM CDTTornado WarningLSXMacoupin, Montgomery25 min
May 31, 8:52 PM CDTTornado WarningLSXBond, Madison, Montgomery23 min
May 31, 8:56 PM CDTTornado WarningLSXMacoupin, Montgomery34 min
May 31, 9:07 PM CDTTornado WarningLSXMacoupin23 min
May 31, 9:13 PM CDTTornado WarningLSXBond, Fayette, Marion, Montgomery32 min
May 31, 9:21 PM CDTSevere Thunderstorm WarningLSXBond, Clinton, Madison, Saint Clair54 min
May 31, 9:43 PM CDTSevere Thunderstorm WarningLSXFayette47 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 10.8 hours before the alert went out and 256 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-pSkew-T log-p diagram, Lincoln, IL at 12:00Z on 2013-05-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 8 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lincoln, IL at 12:00Z on 2013-05-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 215 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
8 J/kg
Mixed-layer CIN
-299 J/kg
Mixed-layer LCL
1021 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
215 m²/s²
0-3 km storm-relative helicity
222 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

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

763 
WWUS20 KWNS 312247
SEL3  
SPC WW 312247
ILZ000-MOZ000-010300-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 263
NWS STORM PREDICTION CENTER NORMAN OK
545 PM CDT FRI MAY 31 2013

THE NWS STORM PREDICTION CENTER HAS ISSUED A

* TORNADO WATCH FOR PORTIONS OF 
  SOUTHWEST AND WEST CENTRAL ILLINOIS
  EAST CENTRAL MISSOURI

* EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 545 PM UNTIL
  1000 PM CDT.

* PRIMARY THREATS INCLUDE...
  SEVERAL TORNADOES POSSIBLE
  SEVERAL DAMAGING WIND GUSTS TO 70 MPH LIKELY
  SEVERAL LARGE HAIL EVENTS TO 1.5 INCHES IN DIAMETER POSSIBLE

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 55 STATUTE
MILES NORTH AND SOUTH OF A LINE FROM 20 MILES NORTH NORTHWEST OF
VICHY MISSOURI TO 25 MILES EAST OF ALTON ILLINOIS.  FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU3).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS.

&&

OTHER WATCH INFORMATION...CONTINUE...WW 260...WW 261...WW 262...

DISCUSSION...A MESOSCALE CONVECTIVE SYSTEM NOW DEVELOPING ACROSS
CENTRAL MISSOURI IS EXPECTED TO SPREAD INTO THE ST. LOUIS
METROPOLITAN AREA DURING THE 00-03Z TIME FRAME...ACCOMPANIED BY THE
RISK FOR SEVERE WIND GUSTS...HAIL AND THE RISK FOR A COUPLE OF
TORNADOES.  IT DOES NOT APPEAR OUT OF THE QUESTION THAT ONE OR TWO
DISCRETE SUPERCELLS COULD ALSO FORM IN ADVANCE OF THE PRIMARY
EVOLVING STORM CLUSTER.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 24040.


...KERR

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 30, 7:04 PM CDTMesoscale DiscussionSPCBond, Boone, Calhoun, Champaign, Christian, Clark and 56 more56 min
May 30, 7:38 PM CDTSevere Thunderstorm WatchSPCChampaign, Christian, Clark, Clay, Coles, Crawford and 12 more5 hr
May 30, 10:03 PM CDTMesoscale DiscussionSPCChampaign, Clark, Clay, Coles, Cook, Crawford and 11 more87 min
May 31, 8:45 AM CDTMesoscale DiscussionSPCBond, Calhoun, Clinton, Greene, Jersey, Macoupin and 5 more90 min
May 31, 5:21 PM CDTMesoscale DiscussionSPCCalhoun, Christian, Greene, Jersey, Logan, Macoupin and 4 more54 min
May 30, 7:41 PM CDTMesoscale DiscussionSPCAtchison2 hr
May 30, 8:46 PM CDTTornado WatchSPCDunklin, Pemiscot7 hr
May 31, 1:57 AM CDTMesoscale DiscussionSPCButler, Carter, Oregon, Ripley93 min
May 31, 2:05 AM CDTMesoscale DiscussionSPCBuchanan, Clay, Clinton, Jackson, Platte, Ray85 min
May 31, 2:44 AM CDTSevere Thunderstorm WatchSPCBuchanan, Caldwell, Carroll, Cass, Chariton, Clay and 14 more5 hr
May 31, 4:51 AM CDTMesoscale DiscussionSPCCaldwell, Carroll, Cass, Chariton, Clay, Clinton and 11 more114 min
May 31, 7:03 AM CDTMesoscale DiscussionSPCCass, Cooper, Howard, Johnson, Pettis57 min
May 31, 1:49 PM CDTMesoscale DiscussionSPCBarry, Barton, Bates, Benton, Camden, Cass and 29 more116 min
May 31, 2:15 PM CDTTornado WatchSPCBarry, Barton, Bates, Benton, Boone, Callaway and 30 more8 hr

Nearby

Tornado Watches in Missouri, 2013Tornado Watches in Illinois, 2013Every tornado watch in 2013

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.