Alert archive / Ohio / Mesoscale Discussions in 2018
Mesoscale Discussion 1491
The Storm Prediction Center issued this mesoscale discussion at Sep 21, 2018, 3:37 PM EDT for 25 counties in Ohio; 5 counties in Pennsylvania. It was in force for 83 min.
The area
The outline as issued.
The facts
- Issued
- Sep 21, 2018, 3:37 PM EDT (19:37 UTC)
- Expired
- Sep 21, 2018, 5:00 PM EDT
- In force
- 83 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 80%
All 30 counties
Ashland County, OH, Ashtabula County, OH, Carroll County, OH, Columbiana County, OH, Coshocton County, OH, Cuyahoga County, OH, Delaware County, OH, Geauga County, OH, Guernsey County, OH, Holmes County, OH, Knox County, OH, Lake County, OH, Licking County, OH, Mahoning County, OH, Medina County, OH, Morrow County, OH, Muskingum County, OH, Perry County, OH, Portage County, OH, Richland County, OH, Stark County, OH, Summit County, OH, Trumbull County, OH, Tuscarawas County, OH, Wayne County, OH, Crawford County, PA, Erie County, PA, Lawrence County, PA, Mercer County, PA, Venango County, PA
The radar
The Cleveland radar (KCLE), 53 km from the middle of the area, began a volume at 19:37 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 watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Pittsburgh, PA (KAGC), launched 12:00Z, 7.6 hours before the alert went out and 134 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.
- Mixed-layer CAPE
- 391 J/kg
- Mixed-layer CIN
- -67 J/kg
- Mixed-layer LCL
- 999 m above ground
- 0-6 km bulk shear
- 40 kt
- 0-1 km storm-relative helicity
- 142 m²/s²
- 0-3 km storm-relative helicity
- 129 m²/s²
- Significant tornado parameter
- 0.2
- Supercell composite
- 1.8
The text
As transmitted.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 21, 4:32 PM EDT | Severe Thunderstorm Watch | SPC | Ashtabula, Belmont, Carroll, Columbiana, Coshocton, Geauga and 14 more | 4 hr |
| Sep 21, 6:08 PM EDT | Mesoscale Discussion | SPC | Adams, Brown, Scioto | 97 min |
| Sep 21, 7:04 PM EDT | Mesoscale Discussion | SPC | Belmont, Carroll, Columbiana, Coshocton, Guernsey, Harrison and 5 more | 116 min |
| Sep 21, 4:50 PM EDT | Severe Thunderstorm Watch | SPC | Cameron, Clearfield, Elk, McKean, Potter, Warren | 6 hr |
Nearby
Mesoscale Discussions in Ohio, 2018Mesoscale Discussions in Pennsylvania, 2018Every 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.