Alert archive / Illinois / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 220, NWS St. Louis, MO

July 26, 2012Randolph County, Illinois; Sainte Genevieve County, Missouri

NWS St. Louis, MO issued this severe thunderstorm warning at Jul 26, 2012, 4:02 PM CDT for Randolph County, Illinois; Sainte Genevieve County, Missouri. It was in force for 28 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: Jul 26, 2012, 4:02 PM CDT (21:02 UTC)
Expired: Jul 26, 2012, 4:30 PM CDT
In force: 28 min
Issued by: NWS St. Louis, MO
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Randolph County, IL, Sainte Genevieve County, MO

The radar

The St Louis radar (KLSX), 112 km from the middle of the area, began a volume at 21:06 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
Jul 26, 4:29 PM CDT	TSTM WND GST 50	St. Mary, MO

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

The watch it was issued in

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

Issued	Product	Office	Lasted
Jul 26, 1:46 PM CDT	Severe Thunderstorm Watch	SPC	10 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 9.0 hours before the alert went out and 281 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: 98 J/kg
Mixed-layer CIN: -223 J/kg
Mixed-layer LCL: 1355 m above ground
0-6 km bulk shear: 52 kt
0-1 km storm-relative helicity: -83 m²/s²
0-3 km storm-relative helicity: -30 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.2

Open this sounding in Storm Lab

The text

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

325 
WUUS53 KLSX 262102
SVRLSX
ILC157-MOC186-262130-
/O.NEW.KLSX.SV.W.0220.120726T2102Z-120726T2130Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST LOUIS MO
402 PM CDT THU JUL 26 2012

THE NATIONAL WEATHER SERVICE IN ST LOUIS HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTH CENTRAL RANDOLPH COUNTY IN SOUTHWEST ILLINOIS...
  CENTRAL STE. GENEVIEVE COUNTY IN SOUTHEAST MISSOURI...

* UNTIL 430 PM CDT

* AT 401 PM CDT...A SEVERE THUNDERSTORM WAS LOCATED NEAR
  WEINGARTEN...AND MOVING EAST AT 20 MPH.

  HAZARD...QUARTER SIZE HAIL AND 60 MPH WIND GUSTS.

  SOURCE...RADAR INDICATED.

  IMPACT...MINOR DAMAGE TO VEHICLES...ROOFS AND WINDOWS. MINOR TREE
           DAMAGE...WITH LIMBS UP TO ONE INCH IN DIAMETER BROKEN.

* LOCATIONS IMPACTED INCLUDE...
  ST. MARY...RIVER AUX VASES...MINNITH AND KASKASKIA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A
BUILDING.

&&

LAT...LON 3779 9029 3797 9023 3791 8978 3785 8979
      3788 8980 3790 8984 3790 8985 3787 8990
      3787 8994 3782 8999 3774 9005
TIME...MOT...LOC 2103Z 283DEG 19KT 3786 9014

HAIL...1.00IN
WIND...60 MPH

$$

TRUETT

1 follow-up statement

227 
WWUS53 KLSX 262129
SVSLSX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST LOUIS MO
429 PM CDT THU JUL 26 2012

ILC157-MOC186-262139-
/O.EXP.KLSX.SV.W.0220.000000T0000Z-120726T2130Z/
RANDOLPH IL-STE. GENEVIEVE MO-
429 PM CDT THU JUL 26 2012

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL STE. GENEVIEVE AND
SOUTH CENTRAL RANDOLPH COUNTIES WILL EXPIRE AT 430 PM CDT...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED BELOW SEVERE
LIMITS...AND NO LONGER POSES AN IMMEDIATE THREAT TO LIFE OR PROPERTY.

ADDITIONAL STRONG THUNDERSTORMS ARE STILL POSSIBLE...AND A SEVERE 
THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM.

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 3779 9029 3797 9023 3791 8978 3785 8979
      3788 8980 3790 8984 3790 8985 3787 8990
      3787 8994 3782 8999 3774 9005
TIME...MOT...LOC 2129Z 283DEG 19KT 3783 8997

$$

PHILLIPSON

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 26, 3:47 PM CDT	Severe Thunderstorm Warning	LSX	Reynolds	43 min
Jul 26, 4:42 PM CDT	Severe Thunderstorm Warning	LSX	Iron, Madison, Saint Francois	27 min

Nearby

Severe Thunderstorm Warnings in Illinois, 2012 Severe Thunderstorm Warnings in Missouri, 2012 Every severe thunderstorm warning in 2012

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.