Alert archive / Pennsylvania / Snow Squall Warnings in 2020

Snow Squall Warning 1, NWS Pittsburgh, PA

January 8, 2020Clarion County, Venango County, Pennsylvania

NWS Pittsburgh, PA issued this snow squall warning at Jan 8, 2020, 5:36 AM EST for Clarion County, Venango County, Pennsylvania. It was in force for 24 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jan 8, 2020, 5:36 AM EST (10:36 UTC)
Expired: Jan 8, 2020, 6:00 AM EST
In force: 24 min
Issued by: NWS Pittsburgh, PA
Area: Storm-based polygon

Counties Clarion County, PA, Venango County, PA

The radar

The Pittsburgh radar (KPBZ), 100 km from the middle of the area, began a volume at 10:37 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 nearest sounding before it

Pittsburgh, PA (KPIT), launched 00:00Z, 10.6 hours before the alert went out and 108 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 2241 m above ground
0-6 km bulk shear: 64 kt
0-1 km storm-relative helicity: 122 m²/s²
0-3 km storm-relative helicity: 149 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this snow squall 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 snow squall warning went out at Jan 8, 3:55 AM EST, 1 hour 41 minutes earlier.

Area forecast discussion, Jan 8, 3:55 AM EST, 1 hour 41 minutes before

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Hazardous weather outlook, Jan 8, 3:58 AM EST, 1 hour 38 minutes before

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In the hours before

Special weather statement, Jan 8, 3:11 AM EST, 2 hours 25 minutes before

Special Weather Statement
National Weather Service Pittsburgh PA
311 AM EST Wed Jan 8 2020

PAZ007>009-013>016-022-080930-
Armstrong-Jefferson-Forest-Butler-Clarion-Venango-Lawrence-Mercer-
311 AM EST Wed Jan 8 2020

...A LINE OF SNOW SHOWERS WILL AFFECT SOUTHEASTERN
MERCER...VENANGO...NORTHERN LAWRENCE...NORTHERN
BUTLER...JEFFERSON...NORTHERN ARMSTRONG...CLARION AND FOREST
COUNTIES...

At 310 AM EST, a line of snow showers was located near Marienville
to near Grove City. Movement was east at 30 mph. Reduction in
visibility and a quick accumulation of snow on roads are expected.

Locations impacted include...
New Castle...                     Oil City...
Grove City...                     Franklin...
Clarion...                        Brookville...
Marienville...                    Knox...
Rimersburg...                     Sugarcreek...
Slippery Rock...                  Reynoldsville...

This includes the following highways...
  Interstate 79 in Pennsylvania between mile markers 105 and 120.
  Interstate 80 in Pennsylvania between mile markers 17 and 96.
  Interstate 376 in Pennsylvania between mile markers 9 and 13.

LAT...LON 4144 7896 4145 7906 4142 7907 4142 7909
      4134 7909 4135 7902 4138 7897 4126 7874
      4123 7873 4120 7874 4120 7877 4113 7880
      4102 7881 4101 8048 4162 7961 4163 7896
TIME...MOT...LOC 0810Z 288DEG 25KT 4146 7918 4111 8017

Special weather statement, Jan 8, 4:30 AM EST, 1 hour 6 minutes before

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The office that day

Everything else NWS Pittsburgh, PA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jan 8, 3:11 AM EST	Special Weather Statement	PBZ	Clarion, Forest, Jefferson, Venango	79 min
Jan 8, 4:30 AM EST	Special Weather Statement	PBZ	Clarion, Forest, Jefferson, Venango	75 min
Jan 8, 6:02 AM EST	Special Weather Statement	PBZ	Clarion	28 min
Jan 8, 6:21 AM EST	Special Weather Statement	PBZ	Jefferson	24 min
Jan 8, 6:32 AM EST	Special Weather Statement	PBZ	Clarion, Jefferson	28 min
Jan 8, 7:18 AM EST	Special Weather Statement	PBZ	Clarion, Forest, Jefferson, Mercer, Venango	57 min
Jan 8, 8:16 AM EST	Special Weather Statement	PBZ	Butler, Clarion, Forest, Jefferson, Lawrence, Mercer and 1 more	59 min
Jan 8, 8:29 AM EST	Snow Squall Warning	PBZ	Butler, Lawrence, Mercer, Venango	61 min
Jan 8, 9:21 AM EST	Snow Squall Warning	PBZ	Armstrong, Beaver, Butler, Clarion, Indiana, Jefferson and 2 more	39 min
Jan 8, 10:01 AM EST	Special Weather Statement	PBZ	Armstrong, Butler, Indiana	44 min
Jan 8, 10:08 AM EST	Special Weather Statement	PBZ	Beaver	52 min
Jan 8, 10:45 AM EST	Snow Squall Warning	PBZ	Allegheny, Armstrong, Beaver, Butler, Indiana, Westmoreland	45 min
Jan 8, 3:47 AM EST	Wind Advisory	PBZ	Tucker	11 hr

Nearby

Snow Squall Warnings in Pennsylvania, 2020 Every snow squall 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.