Alert archive / Illinois / Tornado Watches in 2019

Tornado Watch 236

May 24, 201930 counties in Illinois; 18 counties in Iowa

The Storm Prediction Center issued this tornado watch at May 24, 2019, 6:23 PM CDT for 30 counties in Illinois; 18 counties in Iowa. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
May 24, 2019, 6:23 PM CDT (23:23 UTC)
Expired
May 24, 2019, 10:13 PM CDT
In force
4 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
55 kt
All 48 counties

Cedar County, IA, Clinton County, IA, Des Moines County, IA, Dubuque County, IA, Henry County, IA, Iowa County, IA, Jackson County, IA, Jefferson County, IA, Johnson County, IA, Jones County, IA, Keokuk County, IA, Lee County, IA, Linn County, IA, Louisa County, IA, Muscatine County, IA, Scott County, IA, Van Buren County, IA, Washington County, IA, Bureau County, IL, Carroll County, IL, Fulton County, IL, Grundy County, IL, Hancock County, IL, Henderson County, IL, Henry County, IL, Jo Daviess County, IL, Knox County, IL, LaSalle County, IL, Lee County, IL, Livingston County, IL, Logan County, IL, Marshall County, IL, Mason County, IL, McDonough County, IL, McLean County, IL, Mercer County, IL, Ogle County, IL, Peoria County, IL, Putnam County, IL, Rock Island County, IL, Schuyler County, IL, Stark County, IL, Stephenson County, IL, Tazewell County, IL, Warren County, IL, Whiteside County, IL, Winnebago County, IL, Woodford County, IL

The radar

The Quad Cities radar (KDVN), 27 km from the middle of the area, began a volume at 23:23 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
50%
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
50%
One or more hailstones of 2 inches or more
30%
Six or more combined severe hail and wind reports
80%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
May 24, 6:52 PM CDTTornado Warning Tornado observedDVNCedar, Johnson, Muscatine53 min
May 24, 8:08 PM CDTSevere Thunderstorm WarningILXKnox52 min
May 24, 8:15 PM CDTTornado WarningDVNDubuque27 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

Davenport, (KDVN), launched 12:00Z, 11.4 hours before the alert went out and 22 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, Davenport, at 12:00Z on 2019-05-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Davenport, at 12:00Z on 2019-05-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 428 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
954 m above ground
0-6 km bulk shear
69 kt
0-1 km storm-relative helicity
428 m²/s²
0-3 km storm-relative helicity
568 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.4

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 24, 12:15 PM CDTMesoscale DiscussionSPCAdams, Brown, Cass, Champaign, Christian, Coles and 28 more90 min
May 24, 12:36 PM CDTTornado WatchSPCCass, Champaign, DeWitt, Ford, Fulton, Iroquois and 15 more4 hr
May 24, 3:25 PM CDTMesoscale DiscussionSPCCarroll, Henderson, Henry, Jo Daviess, Knox, Mercer and 5 more65 min
May 24, 4:05 AM CDTMesoscale DiscussionSPCAdams, Fremont, Mills, Montgomery, Page, Ringgold and 2 more115 min
May 24, 4:40 AM CDTSevere Thunderstorm WatchSPCAdams, Appanoose, Clarke, Davis, Decatur, Fremont and 13 more4 hr
May 24, 6:43 AM CDTMesoscale DiscussionSPCAdams, Appanoose, Clarke, Davis, Decatur, Fremont and 13 more2 hr

Nearby

Tornado Watches in Illinois, 2019Tornado Watches in Iowa, 2019Every tornado watch in 2019

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.