Alert archive / Illinois / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 34, NWS St. Louis, MO

April 9, 2011Jersey County, Madison County, Illinois; Saint Charles County, Saint Louis County, Missouri

NWS St. Louis, MO issued this severe thunderstorm warning at Apr 9, 2011, 5:08 AM CDT for Jersey County, Madison County, Illinois; Saint Charles County, Saint Louis County, Missouri. It was in force for 22 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
Apr 9, 2011, 5:08 AM CDT (10:08 UTC)
Expired
Apr 9, 2011, 5:30 AM CDT
In force
22 min
Issued by
NWS St. Louis, MO
Area
Storm-based polygon
Hail
1.0 in
Wind
50.0 mph

Counties Jersey County, IL, Madison County, IL, Saint Charles County, MO, Saint Louis County, MO

The radar

The St Louis radar (KLSX), 32 km from the middle of the area, began a volume at 10:07 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 nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 10.1 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-pSkew-T log-p diagram, Lincoln, IL at 00:00Z on 2011-04-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lincoln, IL at 00:00Z on 2011-04-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 158 square meters per square second.1939587897Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
637 m above ground
0-6 km bulk shear
47 kt
0-1 km storm-relative helicity
158 m²/s²
0-3 km storm-relative helicity
242 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.

040 
WUUS53 KLSX 091008
SVRLSX
ILC083-119-MOC183-189-091030-
/O.NEW.KLSX.SV.W.0034.110409T1008Z-110409T1030Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
508 AM CDT SAT APR 9 2011

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTH CENTRAL JERSEY COUNTY IN SOUTHWEST ILLINOIS...
  NORTHWESTERN MADISON COUNTY IN SOUTHWEST ILLINOIS...
  NORTHEASTERN ST. CHARLES COUNTY IN EAST CENTRAL MISSOURI...
  NORTH CENTRAL ST. LOUIS COUNTY IN EAST CENTRAL MISSOURI...

* UNTIL 530 AM CDT

* AT 507 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL.  THIS
  STORM WAS LOCATED NEAR ORCHARD FARMS...OR 7 MILES NORTHEAST OF ST.
  CHARLES...AND MOVING NORTHEAST AT 35 MPH.

* LOCATIONS IMPACTED INCLUDE...
  GODFREY...ALTON...GRAFTON...PORTAGE DES SIOUX...ELSAH...WEST ALTON
  AND DELHI.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 60 MILES PER
HOUR...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN. FOR
YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR
HOME OR BUSINESS. HEAVY RAINS FLOOD ROADS QUICKLY SO DO NOT DRIVE
INTO AREAS WHERE WATER COVERS THE ROAD.

&&

LAT...LON 3877 9049 3887 9057 3890 9053 3896 9048
      3897 9046 3908 9024 3890 9010
TIME...MOT...LOC 1008Z 243DEG 31KT 3888 9044
WIND...HAIL <50MPH 1.00IN

$$

TILLY
1 follow-up statement
448 
WWUS53 KLSX 091029
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
529 AM CDT SAT APR 9 2011

ILC083-119-MOC183-189-091039-
/O.EXP.KLSX.SV.W.0034.000000T0000Z-110409T1030Z/
MADISON IL-JERSEY IL-ST. LOUIS MO-ST. CHARLES MO-
529 AM CDT SAT APR 9 2011

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN ST. CHARLES...
NORTH CENTRAL ST. LOUIS...SOUTH CENTRAL JERSEY AND NORTHWESTERN
MADISON COUNTIES WILL EXPIRE AT 530 AM CDT...

THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE WARNED
AREA.

LAT...LON 3877 9049 3887 9057 3890 9053 3896 9048
      3897 9046 3908 9024 3890 9010
TIME...MOT...LOC 1029Z 243DEG 31KT 3896 9023

$$

TES

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 9, 2:46 AM CDTFlash Flood WarningLSXAdams6 hr
Apr 9, 3:00 AM CDTSevere Thunderstorm WarningLSXAdams, Pike33 min
Apr 9, 3:44 AM CDTSevere Thunderstorm WarningLSXCalhoun, Pike31 min
Apr 9, 4:19 AM CDTSevere Thunderstorm WarningLSXCalhoun, Jersey26 min
Apr 9, 5:21 AM CDTSevere Thunderstorm WarningLSXFayette, Montgomery39 min
Apr 9, 5:25 AM CDTSevere Thunderstorm WarningLSXMacoupin, Madison35 min
Apr 9, 5:41 AM CDTSevere Thunderstorm WarningLSXBond, Madison49 min
Apr 9, 5:44 AM CDTAreal Flood AdvisoryLSXCalhoun, Jersey, Macoupin, Madison3 hr
Apr 9, 6:43 AM CDTSevere Thunderstorm WarningLSXFayette, Marion32 min
Apr 9, 10:42 AM CDTRiver Flood WarningLSXAdams32 days
Apr 9, 1:42 AM CDTFlash Flood WarningLSXMarion, Shelby6 hr
Apr 9, 5:04 AM CDTSevere Thunderstorm WarningLSXIron, Madison, Reynolds, Saint Francois41 min

Nearby

Severe Thunderstorm Warnings in Illinois, 2011Severe Thunderstorm Warnings in Missouri, 2011Every severe thunderstorm warning 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.