Alert archive / Indiana / Mesoscale Discussions in 2011

Mesoscale Discussion 1836

August 2, 20114 states

The Storm Prediction Center issued this mesoscale discussion at Aug 2, 2011, 8:34 PM CDT for 4 states. It was in force for 86 min.

The area

The outline as issued.

The facts

Issued
Aug 2, 2011, 8:34 PM CDT (01:34 UTC)
Expired
Aug 2, 2011, 10:00 PM CDT
In force
86 min
Issued by
the Storm Prediction Center
All 35 counties

Cook County, IL, DeKalb County, IL, DuPage County, IL, Grundy County, IL, Kane County, IL, Kankakee County, IL, Kendall County, IL, LaSalle County, IL, Livingston County, IL, Will County, IL, DeKalb County, IN, Elkhart County, IN, Jasper County, IN, Kosciusko County, IN, LaGrange County, IN, Lake County, IN, LaPorte County, IN, Marshall County, IN, Newton County, IN, Noble County, IN, Porter County, IN, Pulaski County, IN, Saint Joseph County, IN, Starke County, IN, Steuben County, IN, Berrien County, MI, Branch County, MI, Calhoun County, MI, Cass County, MI, Hillsdale County, MI, Kalamazoo County, MI, Lenawee County, MI, Saint Joseph County, MI, Fulton County, OH, Williams County, OH

The radar

The Northern Indiana radar (KIWX), 95 km from the middle of the area, began a volume at 01:34 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

Lincoln, IL (KILX), launched 00:00Z, 1.6 hours before the alert went out and 242 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 00:00Z on 2011-08-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3189 joules per kilogram.LCLLFCEL10008507005003002001001 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 00:00Z on 2011-08-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 239 square meters per square second.1939Sfc1 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
3189 J/kg
Mixed-layer CIN
-176 J/kg
Mixed-layer LCL
1419 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
239 m²/s²
0-3 km storm-relative helicity
306 m²/s²
Significant tornado parameter
0.3
Supercell composite
6.2

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 2, 11:25 PM CDTMesoscale DiscussionSPCIroquois95 min
Aug 3, 12:26 PM CDTMesoscale DiscussionSPCPope64 min
Aug 3, 12:48 AM CDTSevere Thunderstorm WatchSPCBoone, Carroll, Clinton, Dearborn, Delaware, Fountain and 14 more8 hr
Aug 3, 3:28 AM CDTMesoscale DiscussionSPCAdams, Athens, Brown, Butler, Champaign, Clark and 44 more92 min
Aug 3, 7:21 AM CDTMesoscale DiscussionSPCAdams, Athens, Brown, Butler, Champaign, Clark and 44 more84 min

Nearby

Mesoscale Discussions in Indiana, 2011Mesoscale Discussions in Illinois, 2011Mesoscale Discussions in Michigan, 2011Every mesoscale discussion in 2011

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.