Alert archive / Illinois / Tornado Warnings in 2018

Tornado Warning 20, NWS St. Louis, MO

December 1, 2018Montgomery County, Illinois

NWS St. Louis, MO issued this tornado warning at Dec 1, 2018, 4:32 PM CST for Montgomery County, Illinois. It was in force for 28 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: Dec 1, 2018, 4:32 PM CST (22:32 UTC)
Expired: Dec 1, 2018, 5:00 PM CST
In force: 28 min
Issued by: NWS St. Louis, MO
Area: Storm-based polygon
Tornado: Observed
Damage threat: Considerable
Hail: 1.75 in

County Montgomery County, IL

The radar

The Lincoln radar (KILX), 96 km from the middle of the area, began a volume at 22:32 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
Dec 1, 2:16 PM CST	Tornado Watch	SPC	7 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 10.5 hours before the alert went out and 120 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 430 m above ground
0-6 km bulk shear: 75 kt
0-1 km storm-relative helicity: 529 m²/s²
0-3 km storm-relative helicity: 658 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

392 
WFUS53 KLSX 012232
TORLSX
ILC135-012300-
/O.NEW.KLSX.TO.W.0020.181201T2232Z-181201T2300Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service St Louis MO
432 PM CST SAT DEC 1 2018

The National Weather Service in St Louis has issued a

* Tornado Warning for...
  Central Montgomery County in south central Illinois...

* Until 500 PM CST.
    
* At 432 PM CST, a confirmed large and extremely dangerous tornado
  was located near Raymond, moving northeast at 35 mph.

  This is a PARTICULARLY DANGEROUS SITUATION. TAKE COVER NOW!

  HAZARD...Damaging tornado.

  SOURCE...Radar confirmed tornado.

  IMPACT...You are in a life-threatening situation. Flying debris 
           may be deadly to those caught without shelter. Mobile 
           homes will be destroyed. Considerable damage to homes, 
           businesses, and vehicles is likely and complete 
           destruction is possible.

* This tornadic thunderstorm will remain over mainly rural areas of
  central Montgomery County, including the following locations...
  Wenonah.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

To repeat, a large, extremely dangerous and potentially deadly
tornado is on the ground. To protect your life, TAKE COVER NOW! Move
to a basement or an interior room on the lowest floor of a sturdy
building. Avoid windows. If you are outdoors, in a mobile home, or in
a vehicle, move to the closest substantial shelter and protect
yourself from flying debris.

&&

LAT...LON 3923 8944 3929 8957 3935 8952 3935 8926
TIME...MOT...LOC 2232Z 216DEG 31KT 3925 8955 

TORNADO...OBSERVED
TORNADO DAMAGE THREAT...CONSIDERABLE
HAIL...1.75IN

$$

TES

2 follow-up statements

357 
WWUS53 KLSX 012246
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
446 PM CST SAT DEC 1 2018

ILC135-012300-
/O.CON.KLSX.TO.W.0020.000000T0000Z-181201T2300Z/
Montgomery IL-
446 PM CST SAT DEC 1 2018

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 500 PM CST FOR CENTRAL
MONTGOMERY COUNTY...
        
At 446 PM CST, a confirmed large and extremely dangerous tornado was
located near Morrisonville, moving northeast at 30 mph.

This is a PARTICULARLY DANGEROUS SITUATION. TAKE COVER NOW!

HAZARD...Damaging tornado.

SOURCE...Radar confirmed tornado.

IMPACT...You are in a life-threatening situation. Flying debris may 
         be deadly to those caught without shelter. Mobile homes 
         will be destroyed. Considerable damage to homes, 
         businesses, and vehicles is likely and complete destruction 
         is possible.

Locations impacted include...
Hillsboro and Wenonah. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

To repeat, a large, extremely dangerous and potentially deadly
tornado is on the ground. To protect your life, TAKE COVER NOW! Move
to a basement or an interior room on the lowest floor of a sturdy
building. Avoid windows. If you are outdoors, in a mobile home, or in
a vehicle, move to the closest substantial shelter and protect
yourself from flying debris.

&&

LAT...LON 3923 8944 3929 8957 3935 8952 3935 8926
TIME...MOT...LOC 2246Z 220DEG 27KT 3933 8946 

TORNADO...OBSERVED
TORNADO DAMAGE THREAT...CONSIDERABLE
HAIL...1.75IN

$$

TES

729 
WWUS53 KLSX 012253 RRA
SVSLSX

Severe Weather Statement
National Weather Service St Louis MO
453 PM CST SAT DEC 1 2018

ILC135-012303-
/O.EXP.KLSX.TO.W.0020.000000T0000Z-181201T2300Z/
Montgomery IL-
453 PM CST SAT DEC 1 2018

...THE TORNADO WARNING FOR CENTRAL MONTGOMERY COUNTY WILL EXPIRE AT
500 PM CST...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning will be allowed to expire.

A Tornado Watch remains in effect until 700 PM CST for south central
Illinois.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
St Louis.

LAT...LON 3923 8944 3929 8957 3935 8952 3935 8926
TIME...MOT...LOC 2253Z 216DEG 31KT 3937 8942 

$$

TES

The office that day

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

Issued	Product	Office	Counties	Lasted
Dec 1, 3:54 AM CST	Severe Thunderstorm Warning	LSX	Randolph	29 min
Dec 1, 2:17 PM CST	Severe Thunderstorm Warning	LSX	Pike	43 min
Dec 1, 2:21 PM CST	Severe Thunderstorm Warning	LSX	Adams, Brown	20 min
Dec 1, 2:28 PM CST	Severe Thunderstorm Warning	LSX	Pike	30 min
Dec 1, 2:37 PM CST	Tornado Warning	LSX	Pike	25 min
Dec 1, 3:34 PM CST	Severe Thunderstorm Warning	LSX	Greene, Jersey	41 min
Dec 1, 3:57 PM CST	Severe Thunderstorm Warning	LSX	Macoupin, Montgomery	48 min
Dec 1, 4:08 PM CST	Tornado Warning	LSX	Macoupin, Montgomery	37 min
Dec 1, 4:28 PM CST	Tornado Warning Tornado observed	LSX	Montgomery	17 min
Dec 1, 4:39 PM CST	Severe Thunderstorm Warning	LSX	Macoupin	51 min
Dec 1, 4:43 PM CST	Tornado Warning	LSX	Montgomery	14 min

Nearby

Tornado Warnings in Illinois, 2018 Every tornado warning in 2018 Tornadoes in 2018

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.