Alert archive / Illinois / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 3, NWS Lincoln, IL

February 28, 2017Knox County, Illinois

NWS Lincoln, IL issued this severe thunderstorm warning at Feb 28, 2017, 4:11 PM CST for Knox County, Illinois. It was in force for 36 min. 2 reports 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: Feb 28, 2017, 4:11 PM CST (22:11 UTC)
Expired: Feb 28, 2017, 4:47 PM CST
In force: 36 min
Issued by: NWS Lincoln, IL
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

County Knox County, IL

The radar

The Quad Cities radar (KDVN), 96 km from the middle of the area, began a volume at 22:13 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
Feb 28, 4:30 PM CST	HAIL 0.25	Knoxville, IL	.
Feb 28, 4:35 PM CST	HAIL 0.25	1 S Gilson, IL	.

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
Feb 28, 2:57 PM CST	Tornado Watch	SPC	7 hr

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 10.2 hours before the alert went out and 95 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: 30 J/kg
Mixed-layer CIN: -241 J/kg
Mixed-layer LCL: 771 m above ground
0-6 km bulk shear: 80 kt
0-1 km storm-relative helicity: 223 m²/s²
0-3 km storm-relative helicity: 294 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.0

Open this sounding in Storm Lab

The text

As transmitted.

573 
WUUS53 KILX 282211
SVRILX
ILC095-282300-
/O.NEW.KILX.SV.W.0003.170228T2211Z-170228T2300Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Lincoln IL
411 PM CST TUE FEB 28 2017

The National Weather Service in Lincoln has issued a

* Severe Thunderstorm Warning for...
  Southern Knox County in west central Illinois...

* Until 500 PM CST

* At 411 PM CST, a severe thunderstorm was located near Little Swan
  Lake, or 13 miles southeast of Monmouth, moving east at 55 mph.

  HAZARD...60 mph wind gusts and quarter size hail. 

  SOURCE...Radar indicated. 

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees. 

* Locations impacted include...
  Galesburg, Abingdon, Knoxville, Yates City, Williamsfield, London
  Mills, Maquon, Gilson, East Galesburg, St. Augustine, Dahinda and
  Delong.

This includes Interstate 74 between mile markers 49 and 67.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

A tornado watch remains in effect for the warned area. Tornadoes can
develop quickly from severe thunderstorms. Although a tornado is not
immediately likely, if one is spotted, act quickly and move to a
place of safety inside a sturdy structure such as a basement or small
interior room.

&&

A tornado watch remains in effect until 1000 PM CST for west central
Illinois.

LAT...LON 4071 8999 4071 9040 4072 9044 4091 9044
      4103 8999
TIME...MOT...LOC 2211Z 249DEG 46KT 4075 9050 

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

Shimon

2 follow-up statements

299 
WWUS53 KILX 282229
SVSILX

Severe Weather Statement
National Weather Service Lincoln IL
429 PM CST TUE FEB 28 2017

ILC095-282300-
/O.CON.KILX.SV.W.0003.000000T0000Z-170228T2300Z/
Knox-
429 PM CST TUE FEB 28 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 500 PM CST
FOR SOUTHERN KNOX COUNTY...

At 428 PM CST, a severe thunderstorm was located near Maquon, or 13
miles southeast of Galesburg, moving east at 50 mph.

HAZARD...60 mph wind gusts and quarter size hail. 

SOURCE...Radar indicated. 

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees. 

Locations impacted include...
Galesburg, Abingdon, Knoxville, Yates City, Williamsfield, Maquon,
Gilson, East Galesburg, Dahinda and Delong.

This includes Interstate 74 between mile markers 49 and 67.
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...

A tornado watch remains in effect for the warned area. Tornadoes can
develop quickly from severe thunderstorms. Although a tornado is not
immediately likely, if one is spotted act quickly and move to a place
of safety inside a sturdy structure, such as a basement or small
interior room.

&&

A tornado watch remains in effect until 1000 PM CST for west central
Illinois.

LAT...LON 4071 8999 4072 9029 4079 9044 4091 9044
      4103 8999
TIME...MOT...LOC 2228Z 250DEG 44KT 4080 9023 

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

Shimon

623 
WWUS53 KILX 282247
SVSILX

Severe Weather Statement
National Weather Service Lincoln IL
447 PM CST TUE FEB 28 2017

ILC095-282257-
/O.CAN.KILX.SV.W.0003.000000T0000Z-170228T2300Z/
Knox-
447 PM CST TUE FEB 28 2017

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN KNOX COUNTY IS
CANCELLED...
        
The storm which prompted the warning has moved out of the area.
Therefore the warning has been cancelled.

A tornado watch remains in effect until 1000 PM CST for west central
Illinois.

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

LAT...LON 4071 8999 4072 9029 4079 9044 4091 9044
      4103 8999
TIME...MOT...LOC 2246Z 249DEG 46KT 4089 8992 

$$

Shimon

The office that day

Everything else NWS Lincoln, IL issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Feb 28, 3:35 PM CST	Severe Thunderstorm Warning	ILX	Stark	25 min
Feb 28, 3:50 PM CST	Severe Thunderstorm Warning	ILX	Knox	26 min
Feb 28, 4:33 PM CST	Severe Thunderstorm Warning	ILX	Morgan, Scott	29 min
Feb 28, 4:44 PM CST	Severe Thunderstorm Warning	ILX	Marshall, Peoria, Stark	51 min
Feb 28, 5:05 PM CST	Tornado Warning	ILX	Marshall, Peoria, Woodford	25 min
Feb 28, 5:28 PM CST	Tornado Warning Tornado observed	ILX	Marshall, Woodford	32 min
Feb 28, 5:32 PM CST	Severe Thunderstorm Warning	ILX	Marshall	28 min
Feb 28, 5:36 PM CST	Tornado Warning	ILX	Christian	24 min

Nearby

Severe Thunderstorm Warnings in Illinois, 2017 Every severe thunderstorm warning in 2017

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.