Powerful Pacific System Impacting the West; First Significant Snow for Portions of the East

Power Pacific system will continue to bring significant impacts for Pacific Northwest into northern California the remainder of the week. Dangerous coastal affects, heavy rain, flooding, strong winds, and higher elevation mountain snow continues. Meanwhile, a storm across the east is set to bring the first accumulating snow to many higher elevations of the Catskills into the central Appalachians. Read More >

Overview

A closed low pressure system moved slowly across the northern Plains May 12, 2023. This system was responsible for multiple tornadoes across portions of north central Nebraska.

Preliminary Storm Survey from Saturday, May 13 across portions of north central Nebraska:

The National Weather Service office in North Platte, NE sent a survey team to multiple locations across north central Nebraska. The preliminary survey determined that 7 tornadoes occurred across portions of Custer, Garfield, Wheeler, and Holt Counties. Out of the 7 tornadoes that occurred, 4 of them were rated EF-U due to no damage being observed.

Public Information Statement

Tornado
Photos & Video
Radar
Environment
Additional

Tornadoes:

Tornado - Anselmo
Custer County

Date	May 12, 2023
Time (Local)	12:34 to 12:48 PM CT
EF Rating	EF-1
Est. Peak Winds	110 mph
Path Length	4.02 miles
Max Width	100 yards
Injuries/Deaths	0/0
Summary: The tornado moved to the northwest, casing extensive tree damage on the west side of Anselmo.

Track Map

Track Map

EF-Scale

Tornado - Bartlett
Wheeler County

Date	May 12, 2023
Time (Local)	3:11 to 3:20 PM CT
EF Rating	EF-1
Est. Peak Winds	107 mph
Path Length	3.42 miles
Max Width	50 yards
Injuries/Deaths	0/0
Summary: This tornado touched down and mainly impacted open areas. However, a few stands of trees were damaged, with trunks snapped and large limbs lost.

Track Map

Track Map

EF-Scale

Tornado - Chambers
Holt County

Date	May 12, 2023
Time (Local)	3:55 to 4:06 PM CT
EF Rating	EF-2
Est. Peak Winds	120 mph
Path Length	7.85 miles
Max Width	75 yards
Injuries/Deaths	0/0
Summary: This tornado touched down in far northern Wheeler County, quickly strengthened and caused extensive damage to shelter belts. Debarking was observed in trees along the county line. The tornado continued northwestward into Holt County, damaging additional trees, farm outbuildings, and pivot systems.

Track Map

Tornado - Arnold
Custer County

Date	May 12, 2023
Time (Local)	More info in summary
EF Rating	EF-U
Est. Peak Winds	Unknown mph
Path Length	Unknown miles
Max Width	Unknown yards
Injuries/Deaths	0/0
Summary: Three brief tornadoes touched down north of Arnold: EF-U Tornado 4 N of Arnold - 12:42 to 12:43 PM CT EF-U Tornado 5 NNW of Arnold - 12:47 to 12:48 PM CT EF-U Tornado 6 N of Arnold - 4:00 to 4:01 PM CT These three EF-U tornadoes all touched down in an open field. No damage was observed.

Track Map

Track Map

EF-Scale

Tornado - Ericson
Wheeler County

Date	May 12, 2023
Time (Local)	3:25 to 3:33 PM CT
EF Rating	EF-U
Est. Peak Winds	Unknown mph
Path Length	Unknown miles
Max Width	Unknown yards
Injuries/Deaths	0/0
Summary: This tornado touched down in open country northwest of Ericson. No damage was observed, however, video evidence supports the occurrence of this tornado.

Track Map

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

Photos & Video

Tornado Images


Bartlett EF-1 Tornado (Hunter Fowkes)	Bartlett EF-1 Tornado crossing Highway 281 (Jake Heitman)	Ericson EF-U Tornado (Shane Ornelas)	Funnel Cloud north of Arnold. (Michael Schmitt)

Damage Photos for the EF-1 Anselmo Tornado


Snapped healthy hardwood tree (National Weather Service)	Trees snapped and uprooted (National Weather Service)	Snapped healthy pine tree (National Weather Service)

Damage Photos for the EF-1 Bartlett Tornado


Tree trunks snapped (National Weather Service)	Healthy tree snapped (National Weather Service)	Limbs carried into field (National Weather Service)

Damage Photos for the EF-2 Chambers Tornado


Partial debarking of upper branches in a healthy tree (National Weather Service)	Partial debarking of upper branches in a healthy tree (National Weather Service)	Healthy tree uprooted and pivots flipped over (National Weather Service)

Radar

Header


KLNX Radar Image - 5/12/2023 at 12:37 PM CT Anselmo EF-1 Tornado Reflectivity top left, storm relative velocity top right, differential reflectivity bottom left, correlation coefficient bottom right.	KLNX Radar Image - 5/12/2023 at 3:37 PM CT Bartlett EF-1 Tornado Reflectivity top left, storm relative velocity top right, differential reflectivity bottom left, correlation coefficient bottom right.	KLNX Radar Image - 5/12/2023 at 4:02 PM CT Chambers EF-2 Tornado Reflectivity top left, storm relative velocity top right, differential reflectivity bottom left, correlation coefficient bottom right.

Environment

Synoptic summary:


Figure 1: 500 mb pattern 5/12/2023 at 12z	Figure 2: 850 mb pattern 5/12/2023 at 12z	Figure 3: KLBF Upper Air Sounding 5/12/2023 at 12z

Near-storm environment summary:


Figure 4: Mean Sea Level Pressure (MSLP) 5/12/2023 at 23z	Figure 5: Surface Based CAPE (SBCAPE) 5/12/2023 at 23z	Figure 6: Effective Bulk Shear 5/12/2023 at 23z

Additional environmental data:


Figure 7: Significant Tornado Parameter (STP) 5/12/2023 at 23z	Figure 8: Violent Tornado Parameter (VTP) 5/12/2023 at 23z	Figure 9: 0-1km Energy Helicity Index (EHI) 5/12/2023 at 23z