|
A severe weather outbreak affected the southeastern part of the US, with many tornadoes touching down in Mississippi and Alabama, with the strongest tornado touching down near Rolling Fork, MS, tracking nearly 100 km with a preliminary rating of EF4, killing at least 20 people. Overall, at least 26 weather-related deaths have been reported.
A short-wave trough quickly moving eastwards from the Pacific, induced a severe weather outbreak over the southeastern part of the US. After the trough passed the Four Corners region, strong cyclogenesis upstream of the trough was observed over northeastern Texas and southeastern Oklahoma starting around midday on Friday, March 24, 2023. In the following hours the surface low intensified considerably, while tracking northeastwards.
|
500 hPa Geopotential and sea-level pressure (top), 850 hPa pseudo-potential temperature (middle) and 500 hPa vertical velocity (bottom), 31.12.2022 00 UTC until 01.01.2023 12 UTC, source:
wetter3
|
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
Upstream of the trough moist and warm air masses were advected northwards, locally causing daily temperature records on Thursday, March 23, 2023. On the backside of the trough much drier air masses were advected southwards, creating a boundary layer with considerable temperature gradients, creating high instability in the atmosphere. With the short-wave trough, a strong mid-level lift is induced in this region, creating an environment favorable for severe weather development. With strong upper-level westerlies, a strong vertical wind shear is observed, as low-level southwesterlies were dominating ahead of the trough, creating an environment favorable for supercell development, with CAPE-values ranging between 1000-2000 J/kg.
|
Atmospheric sounding of Jackson, MS from 25.03.2023 00 UTC, source:
SPC
|
 |
Thunderstorms started developing on Friday, March 24, 2023, with organized development being observed in the afternoon hours. A particularly strong supercell developed over Mississippi in the afternoon and evening hours, spawning a tornado southwest of Rolling Forks, MS. The violent tornado hit the city directly. With a diameter of more than 1,2 km, the tornado levelled many buildings, killing at least 12 people within the town. The tornado continued to track northeastwards, lasting more than 70 minutes, travelling nearly 100 km in the time. The small-town Silver City, MS was also severely affected by the tornado, destroying parts of the town. Overall, this tornado alone is suspected to have caused at least 20 deaths, with a preliminary rating of EF4.
The same thunderstorm formed another strong EF3-tornado, touching down near Black Hawk, MS. Overall, the severe weather outbreak on Friday, March 24 and Saturday, March 25, 2023, led to the formation of 13 confirmed tornadoes with widespread damage in Mississippi and Alabama.
|
Storm reports across the US from 24.03.2023 12 UTC to 25.03.2023 12 UTC, source:
SPC
|
 |
In total, this severe weather outbreak led to the death of at least 26 people, with ongoing rescue measures. The state of emergency was declared by the Mississippi Governor for the counties severely affected by the tornadoes. The low-level system is currently still active, with strong thunderstorm activity being observed in a line spanning from southern Mississippi into the western parts of South Carolina, with an enhanced potential for tornado development in the southern parts of Mississippi and Alabama today.
Text: KG
March 26, 2023
|
