August 6, 2024 Severe Thunderstorms (2024)

Overview

In the morning of August 6, a supercell developed and tracked east-southeast through southern Michigan, far northeast Indiana and far northwest Ohio. This storm produced an EF2 tornado in northwest St. Joseph county from Lewis Lake to the north side of Three Rivers. This storm did weaken with eastward extent but did maintain some rotation with reports of wall clouds and funnel clouds. Additional thunderstorms then developed east of I-69 Tuesday afternoon, with a few reports of wind damage in northwest Ohio.

Tornado
Radar
Storm Reports
Environment

Tornadoes:

Tornado -Howardsville to Three Rivers
St. Joseph County, MI

Date	August 6, 2024
Time (Local)	8:19 AM - 8:33 AM EDT
EF Rating	EF2
Est. Peak Winds	115 mph
Path Length	8.46 miles
Max Width	700 yards
Injuries/Deaths	0/0
Summary: A tornado touched down Tuesday morning at the county line border, just north of Lewis Lake. The tornado did significant tree damage and snapped power poles along the entirety of Berry Ln. The tornado moved southeast towards Day Rd where it reached maximum width of approximately 700 yards. Here, a well anchored manufactured home was slid approximately 5 feet off its foundation, along with significant tree damage. Near the intersection of Bent Rd. and Floating Bridge Rd. the tornado completely destroyed a barn. Farther east on Floating Bridge Rd., the tornado removed a two-story barn roof completely off and moved it about 30 feet away. The tornado reached maximum intensity of EF-2 along Floating Bridge Rd. Another barn roofreceived major roof damage, the residence's roof was partially removed, and significant tree damage was also observed. The tornado continued southeast crossing Mount Zion Rd with majortree damage and center pivots being overturned. Near Pulver and Null Rd., 8 power poles were snapped, an irrigation pivot was twisted, and minor/moderate roof damage was observed to three homes. Farther southeast along Cowling Rd, a well constructedshed was moved 20-30ft away from its foundation and part of thestructure was thrown into the Rocky River. Finally, the tornado caused minor roof damage to a warehouse along N. Main St in Three Rivers. While a portion of the roof was thrown into the treesacross the street, it is believed this is where the tornado terminated.

Track Map

See Also

Fishing Reports and Forecasts

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


Extensive tree damage southeast of Howardsville, MI in St. Joseph County MI. (Chris Burrows)	Trees down and roofing removed near Marcellus, MI (Cicily Porter WSBT )	Structure damage in Marcellus, MI (Cicily Porter WSB)	Tree damage north of Lewis Lake in Cass County, MI. (Oliver Moster ABC57)


Tree damage north of Lewis Lake in Cass County, MI. (Oliver Moster ABC57)	The upper story of a barn was lofted by a tornado that moved through St. Joseph County MI. (NWS Survey)	An entire outbuilding was destroyed by a tornado that moved through St. Joseph County MI. (NWS Survey)	Significant tree damage was observed along the tornado track that moved through St. Joseph County MI. (NWS Survey)

Radar


Gif of the storm near Bryan OH that elicited a severe thunderstorm warning. Notice how 60 dBZ reached the -20C line (red) and then fell to the ground. Often this scenario produces damaging winds and heavy rain, and depending on the environment, can produce large hail.	Radar image the tornado-producing supercell. Upper left panel is reflectivity, upper right panel is storm relative velocity, bottom left is spectrum width and NROT is on the bottom left.

Storm Reports

Preliminary Local Storm Report...SummaryNational Weather Service Northern Indiana906 PM EDT Tue Aug 6 2024..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON.....DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE.... ..REMARKS..1016 AM Tstm Wnd Dmg 2 SSW Pioneer 41.65N 84.57W08/06/2024 Williams OH Trained Spotter Trees down in the area. 1017 AM Tstm Wnd Dmg 3 ENE Lake Seneca 41.70N 84.61W08/06/2024 Williams OH Trained Spotter Tree damage near intersection of County Road 11 and Road S. 0342 PM Tstm Wnd Dmg 1 N West Leipsic 41.12N 84.00W08/06/2024 Putnam OH Emergency Mngr Several trees and power lines downed across eastern portions of Putnam County. 10-13 power lines down on County Road 7 north of US 224. Trees blocking road on County Road 5. 0250 PM Tstm Wnd Dmg 3 NW Malinta 41.36N 84.08W08/06/2024 Henry OH Emergency Mngr Large tree limbs down at County Roads 11C and N. Time estimated from Radar. 0231 PM Tstm Wnd Dmg 1 NW Okolona 41.36N 84.23W08/06/2024 Defiance OH Emergency Mngr A 20 foot tree was down in Okolona. Time estimated from radar. 0253 PM Tstm Wnd Gst 3 NW Brunersburg 41.33N 84.43W08/06/2024 M58 MPH Defiance OH ASOS ASOS station KDFI Defiance. 0320 PM Tstm Wnd Dmg 2 S Ayersville 41.21N 84.29W08/06/2024 Defiance OH Public Power lines downed. 0820 AM Tstm Wnd Dmg 2 W Howardsville 42.03N 85.76W08/06/2024 St. Joseph MI Trained Spotter Large tree limbs down near Highway 216 and Lewis Lake Drive. Time estimated from radar. 0829 AM Tstm Wnd Dmg 3 SW Moore Park 41.98N 85.66W08/06/2024 St. Joseph MI Emergency Mngr Reports of trees and power lines down in the area of Pulver Rd and Null Road. Time estimated from radar. 0832 AM Tstm Wnd Dmg 1 N Three Rivers 41.96N 85.64W08/06/2024 St. Joseph MI Broadcast Media Several large tree limbs down and power pole damage near Main Street and Barnard Avenue. 1016 AM Tstm Wnd Dmg 5 SSW Frontier 41.71N 84.63W08/06/2024 Hillsdale MI Trained Spotter Large tree down near Territorial Road and Hillsdale Road. Time estimated from radar. 0941 AM Funnel Cloud Kinderhook 41.80N 85.01W08/06/2024 Branch MI Trained Spotter Report of a funnel cloud near the intersection of S Angola Rd and E Copeland Rd.

Environment

A cold front was moving slowly east-southeast through the day. This the primary forcing mechanism for severe thunderstorms.


Figure 1: 8am EDT Surface Analysis. The stationary front extending into southwest Michigan added additional vorticity to severe thunderstorms there.	Figure 2: 11am EDT Surface Analysis. The strongest thunderstorms moves along the warm front, analyzed here east of the low pressure center.	Figure 3: 2pm EDT Surface Analysis. Amid a hot and humid environment, this front continued to produce severe thunderstorms, this time in northwest Ohio.

Near-storm environment summary.


Figure 4: Effective shear at 8am showing how much shear was accessible to storms. We look for 30 kts of effective shear as a starting point usually, but this was more than 2x that in the area of the storm.	Figure 5: Effective helicity at 8am showing how much turning was accessible to storms. We look for around 200 m2/s2 usually.	Figure 6: LCLs indicate how saturated the lowest portion of the column of air was that the storm formed in.

Additional environmental data.


Figure 7: Given that this occurred in the morning, instability was the limiting factor for this storm. Also note the blue shading indicating mixed layer CIN which often inhibits the growth of thunderstorms. This storm was able to surpass these limiting factors and become severe/tornadic.	Figure 8: Effective Significant Tornado Parameter achieved 1, which is what we normally look for when identifying tornado-capable storms.	Figure 9: Equivalent Potential temperature can be effectively used as a measure of both temperature and moisture. It is a good indicator of boundaries, which can form as a result of a gradient of temperature and/or moisture. Notice how the storm traveled right along the gradient of this parameter.

August 6, 2024 Severe Thunderstorms (2024)

References