Alert archive / Ohio / Mesoscale Discussions in 2018

Mesoscale Discussion 486

May 21, 2018Franklin County, Union County, Indiana; 20 counties in Ohio

The Storm Prediction Center issued this mesoscale discussion at May 21, 2018, 8:03 PM EDT for Franklin County, Union County, Indiana; 20 counties in Ohio. It was in force for 117 min.

The area

The outline as issued.

The facts

Issued: May 21, 2018, 8:03 PM EDT (00:03 UTC)
Expired: May 21, 2018, 10:00 PM EDT
In force: 117 min
Issued by: the Storm Prediction Center

All 22 counties

Franklin County, IN, Union County, IN, Ashland County, OH, Butler County, OH, Champaign County, OH, Clark County, OH, Crawford County, OH, Delaware County, OH, Franklin County, OH, Greene County, OH, Knox County, OH, Logan County, OH, Madison County, OH, Marion County, OH, Miami County, OH, Montgomery County, OH, Morrow County, OH, Preble County, OH, Richland County, OH, Shelby County, OH, Union County, OH, Warren County, OH

The radar

The Cincinnati radar (KILN), 78 km from the middle of the area, began a volume at 00:05 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

Cncnati-Daytn, OH (KILN), launched 00:00Z, 0.1 hours before the alert went out and 77 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 208 J/kg
Mixed-layer CIN: -13 J/kg
Mixed-layer LCL: 1822 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: 19 m²/s²
0-3 km storm-relative helicity: 70 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.

Issued	Product	Office	Counties	Lasted
May 22, 12:57 PM EDT	Mesoscale Discussion	SPC	Dearborn, Decatur, Delaware, Fayette, Franklin, Hancock and 8 more	3 hr
May 22, 1:42 PM EDT	Severe Thunderstorm Watch	SPC	Dearborn, Fayette, Franklin, Ohio, Ripley, Union and 1 more	7 hr
May 22, 3:48 PM EDT	Mesoscale Discussion	SPC	Dearborn, Fayette, Franklin, Ohio, Switzerland, Union and 1 more	117 min
May 22, 6:36 PM EDT	Mesoscale Discussion	SPC	Dearborn, Ohio	114 min
May 21, 10:23 PM EDT	Mesoscale Discussion	SPC	Clinton, Coshocton, Fairfield, Fayette, Franklin, Highland and 5 more	97 min

Nearby

Mesoscale Discussions in Ohio, 2018 Mesoscale Discussions in Indiana, 2018 Every mesoscale discussion 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.