Alert archive / Pennsylvania / Winter Storm Warnings in 2020
Winter Storm Warning 4, NWS Pittsburgh, PA
NWS Pittsburgh, PA issued this winter storm warning at Dec 15, 2020, 3:46 AM EST for 11 counties in Pennsylvania; 5 counties in West Virginia. It took effect at Dec 16, 2020, 7:00 AM EST. It was in force for 22 hr. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Dec 15, 2020, 3:46 AM EST (08:46 UTC)
- In effect from
- Dec 16, 2020, 7:00 AM EST
- Expired
- Dec 17, 2020, 4:40 AM EST
- In force
- 22 hr
- Issued by
- NWS Pittsburgh, PA
Counties Allegheny County, PA, Armstrong County, PA, Beaver County, PA, Butler County, PA, Clarion County, PA, Fayette County, PA, Forest County, PA, Greene County, PA, Jefferson County, PA, Washington County, PA, Westmoreland County, PA, Marion County, WV, Monongalia County, WV, Preston County, WV, Tucker County, WV, Wetzel County, WV
The radar
The Pittsburgh radar (KPBZ), 45 km from the middle of the area, began a volume at 08:47 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
Pittsburgh, PA (KPIT), launched 00:00Z, 8.8 hours before the alert went out and 28 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1035 m above ground
- 0-6 km bulk shear
- 71 kt
- 0-1 km storm-relative helicity
- -51 m²/s²
- 0-3 km storm-relative helicity
- 1 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
What forecasters said that day
The local office's own words before this winter storm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Pittsburgh, PA wrote its last area forecast discussion before this winter storm warning went out at Dec 15, 12:24 AM EST, 3 hours 22 minutes earlier.
Area forecast discussion, Dec 15, 12:24 AM EST, 3 hours 22 minutes before
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</html>The office that day
Everything else NWS Pittsburgh, PA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 15, 3:46 AM EST | Winter Storm Watch | PBZ | Allegheny, Armstrong, Butler, Fayette, Greene, Jefferson and 2 more | 9 hr |
| Dec 15, 1:05 PM EST | Winter Weather Advisory | PBZ | Beaver, Forest, Lawrence, Mercer, Venango | 40 hr |
Nearby
Winter Storm Warnings in Pennsylvania, 2020Winter Storm Warnings in West Virginia, 2020Every winter storm warning in 2020
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.