Alert archive / Pennsylvania / Mesoscale Discussions in 2026
Mesoscale Discussion 271
The Storm Prediction Center issued this mesoscale discussion at Mar 16, 2026, 10:57 AM EDT for 4 counties in New York; 31 counties in Pennsylvania. It was in force for 93 min.
The area
The outline as issued.
The facts
- Issued
- Mar 16, 2026, 10:57 AM EDT (14:57 UTC)
- Expired
- Mar 16, 2026, 12:30 PM EDT
- In force
- 93 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch possible
- Chance of a watch
- 60%
All 35 counties
Broome County, NY, Chemung County, NY, Tioga County, NY, Tompkins County, NY, Adams County, PA, Berks County, PA, Bradford County, PA, Carbon County, PA, Centre County, PA, Chester County, PA, Clinton County, PA, Columbia County, PA, Cumberland County, PA, Dauphin County, PA, Huntingdon County, PA, Juniata County, PA, Lackawanna County, PA, Lancaster County, PA, Lebanon County, PA, Lehigh County, PA, Luzerne County, PA, Lycoming County, PA, Mifflin County, PA, Montour County, PA, Northumberland County, PA, Perry County, PA, Schuylkill County, PA, Snyder County, PA, Sullivan County, PA, Susquehanna County, PA, Tioga County, PA, Union County, PA, Wayne County, PA, Wyoming County, PA, York County, PA
The radar
The State College radar (KCCX), 121 km from the middle of the area, began a volume at 15:01 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
Washington/Dulle, VA (KIAD), launched 12:00Z, 3.0 hours before the alert went out and 239 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
- 131 J/kg
- Mixed-layer CIN
- -49 J/kg
- Mixed-layer LCL
- 644 m above ground
- 0-6 km bulk shear
- 53 kt
- 0-1 km storm-relative helicity
- 270 m²/s²
- 0-3 km storm-relative helicity
- 312 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.3
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 |
|---|---|---|---|---|
| Mar 16, 6:13 PM EDT | Mesoscale Discussion | SPC | Allegany, Cattaraugus, Chautauqua, Erie, Wyoming | 4 hr |
| Mar 16, 11:30 AM EDT | Tornado Watch | SPC | Adams, Berks, Bucks, Carbon, Chester, Columbia and 20 more | 6 hr |
| Mar 16, 3:14 PM EDT | Mesoscale Discussion | SPC | Berks, Bucks, Chester, Delaware, Lancaster, Lehigh and 3 more | 91 min |
Nearby
Mesoscale Discussions in Pennsylvania, 2026Mesoscale Discussions in New York, 2026Every mesoscale discussion in 2026
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.