Alert archive / Missouri / Tornado Watches in 2008

Tornado Watch 147

March 31, 20088 counties in Illinois; 23 counties in Missouri

The Storm Prediction Center issued this tornado watch at Mar 31, 2008, 1:45 PM CDT for 8 counties in Illinois; 23 counties in Missouri. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Mar 31, 2008, 1:45 PM CDT (18:45 UTC)
Expired
Mar 31, 2008, 7:44 PM CDT
In force
6 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt
All 31 counties

Calhoun County, IL, Greene County, IL, Jersey County, IL, Macoupin County, IL, Madison County, IL, Monroe County, IL, Randolph County, IL, Saint Clair County, IL, Audrain County, MO, Boone County, MO, Callaway County, MO, City of Saint Louis, MO, Cole County, MO, Crawford County, MO, Franklin County, MO, Gasconade County, MO, Iron County, MO, Jefferson County, MO, Lincoln County, MO, Madison County, MO, Moniteau County, MO, Montgomery County, MO, Osage County, MO, Pike County, MO, Reynolds 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), 57 km from the middle of the area, began a volume at 18:45 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
50%
One or more gusts of 65 knots or more
40%
Ten or more severe hail reports
70%
One or more hailstones of 2 inches or more
40%
Six or more combined severe hail and wind reports
90%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Mar 31, 2:27 PM CDTSevere Thunderstorm WarningLSXFranklin, Gasconade, Warren48 min
Mar 31, 2:50 PM CDTFlash Flood WarningLSXCole, Gasconade, Osage4 hr
Mar 31, 3:48 PM CDTFlash Flood WarningLSXFranklin, Saint Charles, Warren5 hr
Mar 31, 4:25 PM CDTSevere Thunderstorm WarningLSXMonroe, Saint Clair50 min
Mar 31, 4:43 PM CDTSevere Thunderstorm WarningLSXMonroe, Randolph32 min
Mar 31, 4:50 PM CDTFlash Flood WarningLSXCrawford4 hr
Mar 31, 4:57 PM CDTTornado WarningLSXClinton, Monroe, Randolph, Saint Clair, Washington48 min
Mar 31, 6:44 PM CDTFlash Flood WarningLSXCole, Gasconade, Osage5 hr

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, 6.8 hours before the alert went out and 287 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 2008-03-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 6 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 2008-03-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 197 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
6 J/kg
Mixed-layer CIN
-165 J/kg
Mixed-layer LCL
485 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
197 m²/s²
0-3 km storm-relative helicity
259 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

The text

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

000
WWUS20 KWNS 311841
SEL7  
SPC WW 311841
ILZ000-MOZ000-010200-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 147
NWS STORM PREDICTION CENTER NORMAN OK
145 PM CDT MON MAR 31 2008

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF 

       WEST CENTRAL ILLINOIS
       EAST CENTRAL MISSOURI

EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 145 PM UNTIL 900
PM CDT.

TORNADOES...HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 70 STATUTE
MILES NORTH AND SOUTH OF A LINE FROM 15 MILES WEST OF JEFFERSON
CITY MISSOURI TO 20 MILES SOUTH SOUTHEAST OF SCOTT AFB ILLINOIS. 
FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU7).

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 146...

DISCUSSION...CLUSTER OF INTENSE THUNDERSTORMS OVER CENTRAL MO WILL
TRACK EAST-NORTHEASTWARD INTO WATCH AREA THIS AFTERNOON AND EVENING.
 INCREASINGLY MOIST AND UNSTABLE AIR MASS...COUPLED WITH
STRENGTHENING WIND FIELDS ALOFT WILL PROMOTE A RISK OF SUPERCELL
THUNDERSTORMS CAPABLE OF LARGE HAIL...DAMAGING WINDS...AND ISOLATED
TORNADOES.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 25030.


...HART

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 31, 8:53 AM CDTMesoscale DiscussionSPCBureau, Cass, DeKalb, DeWitt, DuPage, Ford and 24 more2 hr
Mar 31, 1:09 PM CDTMesoscale DiscussionSPCAdams, Brown, Cass, Fulton, Hancock, Henderson and 11 more2 hr
Mar 31, 1:10 PM CDTMesoscale DiscussionSPCBond, Calhoun, Clinton, Greene, Jersey, Macoupin and 6 more35 min
Mar 31, 3:31 AM CDTMesoscale DiscussionSPCAndrew, Bates, Buchanan, Caldwell, Carroll, Cass and 23 more59 min
Mar 31, 4:09 AM CDTSevere Thunderstorm WatchSPCAndrew, Atchison, Buchanan, Caldwell, Clinton, Daviess and 9 more3 hr
Mar 31, 5:59 AM CDTMesoscale DiscussionSPCAndrew, Atchison, Buchanan, Caldwell, Carroll, Clinton and 14 more91 min
Mar 31, 7:50 AM CDTMesoscale DiscussionSPCBarton, Bates, Cedar, Dade, Jasper, Newton and 1 more85 min
Mar 31, 8:44 AM CDTTornado WatchSPCBarry, Barton, Benton, Camden, Cedar, Christian and 23 more7 hr
Mar 31, 10:30 AM CDTMesoscale DiscussionSPCBarry, Barton, Bates, Benton, Camden, Cedar and 24 more60 min
Mar 31, 3:04 PM CDTMesoscale DiscussionSPCBarry, Christian, Dent, Douglas, Greene, Howell and 11 more26 min
Mar 31, 3:45 PM CDTTornado WatchSPCBarry, Christian, Dent, Douglas, Howell, Laclede and 10 more7 hr
Mar 31, 5:28 PM CDTMesoscale DiscussionSPCButler, Dunklin, Ripley, Wayne62 min
Mar 31, 6:12 PM CDTTornado WatchSPCBollinger, Butler, Cape Girardeau, Carter, Dunklin, New Madrid and 6 more7 hr

Nearby

Tornado Watches in Missouri, 2008Tornado Watches in Illinois, 2008Every tornado watch in 2008

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.