Alert archive / Illinois / Tornado Watches in 2018

Tornado Watch 434

December 1, 201829 counties in Illinois; Lincoln County, Pike County, Missouri

The Storm Prediction Center issued this tornado watch at Dec 1, 2018, 2:16 PM CST for 29 counties in Illinois; Lincoln County, Pike County, Missouri. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
Dec 1, 2018, 2:16 PM CST (20:16 UTC)
Expired
Dec 1, 2018, 8:48 PM CST
In force
7 hr
Issued by
the Storm Prediction Center
Largest hail expected
1.5 in
Strongest gust expected
60 kt
All 31 counties

Adams County, IL, Brown County, IL, Calhoun County, IL, Cass County, IL, Christian County, IL, DeWitt County, IL, Fulton County, IL, Greene County, IL, Hancock County, IL, Jersey County, IL, Knox County, IL, Logan County, IL, Macon County, IL, Macoupin County, IL, Mason County, IL, McDonough County, IL, McLean County, IL, Menard County, IL, Montgomery County, IL, Morgan County, IL, Peoria County, IL, Piatt County, IL, Pike County, IL, Sangamon County, IL, Schuyler County, IL, Scott County, IL, Tazewell County, IL, Warren County, IL, Woodford County, IL, Lincoln County, MO, Pike County, MO

The radar

The Lincoln radar (KILX), 8 km from the middle of the area, began a volume at 20:16 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
40%
One or more gusts of 65 knots or more
20%
Ten or more severe hail reports
40%
One or more hailstones of 2 inches or more
20%
Six or more combined severe hail and wind reports
70%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Dec 1, 2:17 PM CSTSevere Thunderstorm WarningLSXPike43 min
Dec 1, 2:21 PM CSTSevere Thunderstorm WarningILXSchuyler39 min
Dec 1, 2:21 PM CSTSevere Thunderstorm WarningLSXAdams, Brown20 min
Dec 1, 2:28 PM CSTSevere Thunderstorm WarningLSXPike30 min
Dec 1, 2:37 PM CSTTornado WarningLSXPike25 min
Dec 1, 2:49 PM CSTTornado WarningILXCass, Morgan, Scott41 min
Dec 1, 2:58 PM CSTSevere Thunderstorm WarningILXSchuyler14 min
Dec 1, 3:04 PM CSTTornado WarningILXSchuyler11 min
Dec 1, 3:05 PM CSTTornado WarningDVNMcDonough25 min
Dec 1, 3:24 PM CSTTornado WarningILXCass, Mason, Schuyler51 min
Dec 1, 3:34 PM CSTSevere Thunderstorm WarningLSXGreene, Jersey41 min
Dec 1, 3:40 PM CSTSevere Thunderstorm WarningDVNMcDonough35 min
Dec 1, 3:42 PM CSTTornado WarningDVNMcDonough33 min
Dec 1, 3:47 PM CSTTornado WarningILXFulton, Mason, Schuyler43 min
Dec 1, 3:57 PM CSTTornado WarningILXKnox, Peoria38 min
Dec 1, 3:57 PM CSTSevere Thunderstorm WarningLSXMacoupin, Montgomery48 min
Dec 1, 4:00 PM CSTTornado WarningDVNMcDonough, Warren30 min
Dec 1, 4:08 PM CSTTornado WarningLSXMacoupin, Montgomery37 min
Dec 1, 4:22 PM CSTTornado WarningILXFulton, Mason, Peoria, Tazewell38 min
Dec 1, 4:28 PM CSTTornado Warning Tornado observedLSXMontgomery17 min
Dec 1, 4:32 PM CSTTornado Warning Tornado observedConsiderable damage threatLSXMontgomery28 min
Dec 1, 4:37 PM CSTTornado WarningILXChristian38 min
Dec 1, 4:39 PM CSTTornado WarningILXChristian51 min
Dec 1, 4:39 PM CSTSevere Thunderstorm WarningLSXMacoupin51 min
Dec 1, 4:42 PM CSTTornado WarningILXMason48 min
Dec 1, 4:43 PM CSTTornado WarningLSXMontgomery14 min
Dec 1, 4:53 PM CSTTornado WarningILXFulton, Peoria37 min
Dec 1, 5:12 PM CSTTornado WarningILXMason, Tazewell48 min
Dec 1, 5:15 PM CSTSevere Thunderstorm WarningILXLogan, Menard, Sangamon45 min
Dec 1, 5:15 PM CSTTornado Warning EmergencyTornado observedCatastrophic damage threatILXChristian30 min
Dec 1, 5:29 PM CSTSevere Thunderstorm WarningILXPeoria46 min
Dec 1, 5:43 PM CSTTornado Warning Tornado observedConsiderable damage threatILXChristian, Macon32 min
Dec 1, 5:46 PM CSTSevere Thunderstorm WarningILXTazewell44 min
Dec 1, 5:54 PM CSTSevere Thunderstorm WarningILXLogan, Menard51 min
Dec 1, 6:13 PM CSTTornado WarningILXDeWitt, Macon32 min
Dec 1, 6:27 PM CSTFlash Flood WarningILXTazewell3 hr
Dec 1, 6:42 PM CSTTornado WarningILXDeWitt, McLean33 min
Dec 1, 7:13 PM CSTTornado Warning Tornado observedConsiderable damage threatILXMcLean32 min
Dec 1, 7:47 PM CSTTornado Warning Tornado observedILXMcLean28 min

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, 8.3 hours before the alert went out and 70 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 2018-12-01Temperature 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°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lincoln, IL at 12:00Z on 2018-12-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 529 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
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

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Dec 1, 1:48 PM CSTMesoscale DiscussionSPCAdams, Bond, Brown, Calhoun, Cass, Christian and 26 more117 min
Dec 1, 5:17 PM CSTMesoscale DiscussionSPCCass, Christian, DeWitt, Ford, Fulton, Knox and 17 more88 min
Nov 30, 9:12 PM CSTMesoscale DiscussionSPCBarry, Barton, Christian, Dade, Douglas, Greene and 6 more2 hr
Nov 30, 9:47 PM CSTTornado WatchSPCBarry, Barton, Cedar, Christian, Dade, Dallas and 19 more5 hr
Nov 30, 11:20 PM CSTMesoscale DiscussionSPCBarry, Barton, Cedar, Christian, Dade, Greene and 8 more85 min
Dec 1, 12:58 AM CSTMesoscale DiscussionSPCCarter, Christian, Douglas, Greene, Howell, Oregon and 9 more2 hr
Dec 1, 3:25 AM CSTMesoscale DiscussionSPCDunklin, Pemiscot2 hr

Nearby

Tornado Watches in Illinois, 2018Tornado Watches in Missouri, 2018Every tornado watch 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.