Alert archive / Missouri / Mesoscale Discussions in 2016

Mesoscale Discussion 479

April 27, 20167 counties in Illinois; 9 counties in Missouri

The Storm Prediction Center issued this mesoscale discussion at Apr 27, 2016, 8:06 PM CDT for 7 counties in Illinois; 9 counties in Missouri. It was in force for 84 min.

The area

The outline as issued.

The facts

Issued
Apr 27, 2016, 8:06 PM CDT (01:06 UTC)
Expired
Apr 27, 2016, 9:30 PM CDT
In force
84 min
Issued by
the Storm Prediction Center

Counties Adams County, IL, Brown County, IL, Greene County, IL, Hancock County, IL, Pike County, IL, Schuyler County, IL, Scott County, IL, Clark County, MO, Knox County, MO, Lewis County, MO, Marion County, MO, Monroe County, MO, Pike County, MO, Ralls County, MO, Scotland County, MO, Shelby County, MO

The radar

The St Louis radar (KLSX), 137 km from the middle of the area, began a volume at 01:08 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 00:00Z, 1.1 hours before the alert went out and 215 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 00:00Z on 2016-04-28Temperature 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 00:00Z on 2016-04-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 338 square meters per square second.1939587897117Sfc1 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
595 m above ground
0-6 km bulk shear
55 kt
0-1 km storm-relative helicity
338 m²/s²
0-3 km storm-relative helicity
343 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 27, 7:59 PM CDTMesoscale DiscussionSPCChristian, Clay, Effingham, Fayette, Jasper, Richland and 1 more91 min

Nearby

Mesoscale Discussions in Missouri, 2016Mesoscale Discussions in Illinois, 2016Every mesoscale discussion in 2016

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.