Strong Storm System Brings Heavy Mountain Snow to the Sierra Nevada and Critical Fire Weather Conditions to the Plains

A Pacific storm system will continue to bring low elevation rain and mountain snow to much of the West through Wednesday, with heavy mountain snow expected in the higher elevations of the Sierra Nevada. This system will also bring strong winds to the Intermountain West, Rockies, and Plains, which will create Critical fire weather conditions for the High Plains. Read More >

Overview

Relatively strong shear and modest instability contributed a severe weather episode across West-Central Pennsylvania during the evening of August 12, 2023. A squall line developed over the western part of the state during the afternoon, then pushed across the Laurel Highlands during the evening hours. An EF0 tornado formed within the squall line in the vicinity of Belsano in Cambria County.

Damage from the tornado near Colver, PA

Tornado
Wind & Hail
Photos & Video
Radar
Storm Reports

Tornadoes:

Tornadoes
CAMBRIA COUNTY

Date	August, 12 2023
Time (Local)	8:49 PM
EF Rating	EF1
Est. Peak Winds	107 mph
Path Length	0.32 miles
Max Width	50 yards
Injuries/Deaths	None
Summary: A supercell embedded in a line of convection produced two tornadoes in the vicinity of Colver, PA, an EF1 just west of town and an EF0 just east of town.

Track Map

Downloadable KMZ File

The Enhanced Fujita (EF) Scale classifies tornadoes into the following categories:

EF0 Weak 65-85 mph	EF1 Moderate 86-110 mph	EF2 Significant 111-135 mph	EF3 Severe 136-165 mph	EF4 Extreme 166-200 mph	EF5 Catastrophic 200+ mph

Environment:

Relatively strong mid level flow/deep layer shear and modest instability was present across Western PA on the evening of August 12, 2023.

Wind

Insert summary here.


A belt of near 50kt winds at 500mb moving into Western PA	CAPEs near 500J/kg across the Laurel Highlands	Several HREF members indicated 2-5km Updraft Helicity values >150, which is supportive of supercells.	HREF STP values near 1 across the Laurel Highlands