Alert archive / Illinois / Mesoscale Discussions in 2014

Mesoscale Discussion 1631

August 28, 201421 counties in Illinois

The Storm Prediction Center issued this mesoscale discussion at Aug 28, 2014, 3:43 PM CDT for 21 counties in Illinois. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Aug 28, 2014, 3:43 PM CDT (20:43 UTC)
Expired
Aug 28, 2014, 5:45 PM CDT
In force
2 hr
Issued by
the Storm Prediction Center
Chance of a watch
20%
All 21 counties

Brown County, IL, Cass County, IL, Christian County, IL, DeWitt County, IL, Fulton County, IL, Logan County, IL, Macon County, IL, Mason County, IL, McDonough County, IL, McLean County, IL, Menard County, IL, Morgan County, IL, Moultrie County, IL, Peoria County, IL, Piatt County, IL, Sangamon County, IL, Schuyler County, IL, Scott County, IL, Tazewell County, IL, Warren County, IL, Woodford County, IL

The radar

The Lincoln radar (KILX), 38 km from the middle of the area, began a volume at 20:42 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 nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 8.7 hours before the alert went out and 164 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 2014-08-28Temperature 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 2014-08-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 56 square meters per square second.193958Sfc1 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
959 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
56 m²/s²
0-3 km storm-relative helicity
115 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 28, 1:12 PM CDTMesoscale DiscussionSPCHancock, Henderson, Mercer, Rock Island, Warren3 hr

Nearby

Mesoscale Discussions in Illinois, 2014Every mesoscale discussion in 2014

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.