Severe Thunderstorms Across Central North Dakota on Wednesday, August 28th and Early Thursday, August 29th, 2024

Tornadoes:

Tornado - 1 mile ESE Steele Kidder County Date August 28, 2024 Time (Local) 7:53 PM EF Rating 1 Est. Peak Winds 100 Path Length 0.86 miles Max Width 300 yards Injuries/Deaths none Summary: Significant damage occurred to an oats crop approximately one mile east-southeast of Steele, with the plants twisted and downed in multiple directions. Approximately one mile east of Steele, over 40 empty train cars were knocked off the tracks. The tracks ran from west to east, with some cars falling north, and some falling south. In addition, near the derailed cars a grove of hardwood trees suffered damage, with a few trees uprooted. The tornado then lifted one mile northeast of Steele. 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

Photos & Video

Damage to a grain bin just south of Sterling, North Dakota. (NWS Bismarck storm survey)	Damage to crops near derailed train cars from the tornado near Steele, North Dakota. (NWS Bismarck storm survey)	A large tree branch that fell on a house in south Bismarck, North Dakota. (Photo courtesy Desaray Schuh)	Back side of a thunderstorm, seen from Riverdale, North Dakota. (Photo courtesy Jeanette Reim)

Derailed train cars from the tornado near Steele, North Dakota. (Photo courtesy Kevin Reski)	Tree damage one mile north of Sterling, North Dakota. (Photo courtesy Michelle Bohlander)	Damage to a grain bin just south of Sterling, North Dakota. (NWS Bismarck storm survey)	Snapped power poles along Highway 83 near Sterling, North Dakota. (NWS Bismarck storm survey)

Radar

Radar loop from 4:50 PM to 2:40 AM CDT

Radar-derived rotation tracks from the storm that produced the tornado near Steele

Storm Reports

Environment

An upper-level low pressure with a strong jet streak wrapping around its base approached the Northern Plains on Wednesday afternoon (Fig. 1 and 2). Ahead of this feature, strong low-level southerly flow advected moisture-rich air from the Gulf of Mexico into the central Dakotas (Fig. 3). At the surface, a cold front was overtaking a warm front across central North Dakota, becoming an occluded front, but a narrow "warm sector" was still present between the two fronts over far south central North Dakota. Despite a mid-level capping inversion sampled by a special balloon sounding at 4 PM CDT (Fig. 5), the surface fronts and associated low pressure system to the north and west provided ample forcing for thunderstorm development along and ahead of the occluded and cold fronts in south central North Dakota during the late afternoon. The atmosphere was highly unstable with over 3000 J/kg of Convective Available Potential Energy (CAPE), a key ingredient for severe storms. Southeast winds at the surface veering to the southwest and increasing with height produced strong vertical wind shear, another key ingredient for severe storms. Low-level wind shear was particularly strong in this setup, which can be seen in the curvature of the red-line portion of the hodograph (upper right of Fig. 5). This created an increased risk for tornadoes.

Figure 1: 300 mb height and wind analysis from 7 PM Wednesday evening. Map from the Storm Prediction Center.	Figure 2: 500 mb height, wind, and temperature analysis from 7 PM Wednesday evening. Map from the Storm Prediction Center.	Figure 3: 850 mb height, wind, temperature , and moisture analysis from 7 PM Wednesday evening. Map from the Storm Prediction Center.

Figure 4: Analyzed surface map from 4 PM Wednesday afternoon. Map from the Weather Prediction Center.	Figure 5: Observed upper air sounding from NWS Bismarck taken at 4 PM Wednesday afternoon.