Alert archive / Pennsylvania / Mesoscale Discussions in 2017
Mesoscale Discussion 919
The Storm Prediction Center issued this mesoscale discussion at May 30, 2017, 12:03 PM EDT for 4 states. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- May 30, 2017, 12:03 PM EDT (16:03 UTC)
- Expired
- May 30, 2017, 2:30 PM EDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 60%
All 32 counties
Allegany County, MD, Garrett County, MD, Allegany County, NY, Chemung County, NY, Schuyler County, NY, Seneca County, NY, Steuben County, NY, Tompkins County, NY, Yates County, NY, Armstrong County, PA, Bedford County, PA, Blair County, PA, Cambria County, PA, Cameron County, PA, Centre County, PA, Clarion County, PA, Clearfield County, PA, Clinton County, PA, Elk County, PA, Fayette County, PA, Forest County, PA, Fulton County, PA, Huntingdon County, PA, Indiana County, PA, Jefferson County, PA, McKean County, PA, Potter County, PA, Somerset County, PA, Tioga County, PA, Westmoreland County, PA, Hampshire County, WV, Mineral County, WV
The radar
The State College radar (KCCX), 25 km from the middle of the area, began a volume at 16:03 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, 4.1 hours before the alert went out and 161 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
- 309 J/kg
- Mixed-layer CIN
- -89 J/kg
- Mixed-layer LCL
- 1205 m above ground
- 0-6 km bulk shear
- 53 kt
- 0-1 km storm-relative helicity
- 115 m²/s²
- 0-3 km storm-relative helicity
- 143 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 0.9
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 |
|---|---|---|---|---|
| May 30, 12:39 PM EDT | Severe Thunderstorm Watch | SPC | Allegany, Broome, Cattaraugus, Cayuga, Chautauqua, Chemung and 30 more | 6 hr |
| May 30, 4:03 PM EDT | Mesoscale Discussion | SPC | Broome, Cayuga, Chemung, Chenango, Cortland, Fulton and 19 more | 117 min |
| May 30, 5:56 PM EDT | Mesoscale Discussion | SPC | Jefferson | 64 min |
Nearby
Mesoscale Discussions in Pennsylvania, 2017Mesoscale Discussions in New York, 2017Mesoscale Discussions in Maryland, 2017Every mesoscale discussion in 2017
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.