EF1 tornado in Anderson County, Kentucky

Severe storms developed west of Lawrenceburg in two waves. One produced

straight line winds as a squall line and moved from west to east into downtown

Lawrenceburg where it caused multiple trees to fall, likely with winds of

80-90 mph. Additionally, a brick building downtown that had been previously

damaged from the March 3rd event suffered additional damage to the brickwork.

The other was a storm that developed just south of that line and caused a

tornado to drop along Highway 44 west of Lawrenceburg starting in the 2200

block where several large trees had fallen along the road but had been cleaned

up by the time the survey occurred. There was significant tree damage along

McDonald Road paralleling Highway 44. The most significant damage occurred

around a square home with pyramid shaped roof. Trees fell without hitting the

home, but fell in multiple directions. No shingles were damaged, but that may

be due to the steepness of the roof. The survey continued ENE with tree

damage on both McDonald and Highway 44 from the 2200 block all they way

to the 1600 block. At the latter location, a barndominium suffered partial roof

damage. Part of the metal roof was torn in one slab and thrown to the east of

the property. The property owner witnessed a circulation approaching and took

shelter in an open garage whose closed doors were blown outwards. At this

point the tornado appeared to lift, but additional damage was reported just

downstream, along Hammonds Creek Rd, where several trees on a property

were uprooted or snapped. The tornado appeared to lift beyond this point and

merge with the main line heading towards Lawrenceburg.

An anomalously strong mid- and upper-level trough for early July was centered over the Plains and gradually moved eastward toward the Ohio Valley on July 1st and 2nd, 2023. A meandering surface frontal boundary gradually became more well defined throughout this period, with a warm front lifting through the Ohio Valley on July 1st before a series of remnant outflow boundaries and a convectively-enhanced cold frontal passage occurred July 2nd into the morning hours of July 3rd. Across central Kentucky and southern Indiana, there was ample fuel for convection, as temperatures in the mid-to-upper 80s and lower 90s and dewpoints in the low-to-mid 60s allowed for the development of over 2500 J/kg of mixed-layer CAPE. Since there was initially no predominant organizing feature for convection, multiple waves of showers and thunderstorms moved across the region on July 1st, producing intermittent instances of damaging straight-line winds and near-severe hail, primarily across southern Indiana. However, as the main trough and the surface cold front moved into the region on July 2nd, convection was better organized thanks to 40-45 knots of effective bulk shear in addition to moderate to high levels of instability. Convective development on July 2nd began during the early afternoon hours across southwestern Indiana and western Kentucky. Initially, convective mode was predominantly cellular, but cells gradually grew upscale through the afternoon into clusters and larger quasi-linear structures. Downdraft CAPE was over 1000 J/kg and significant hail parameter values exceeded 1 through most of the area; accordingly, strong to damaging winds and hail were the primary severe hazards observed during the afternoon and evening hours on July 2nd. However, there was just enough low-level helicity to facilitate the development of two weak tornadoes, one in Anderson County and the other in Casey County. Storms gradually subsided after sunset, with the severe threat ending across the region by midnight on July 3rd.