EF1 tornado in Warren County, Kentucky

The National Weather Service conducted a storm survey on Wednesday, March 18th for the storms that occurred on Sunday night, March 15th. A tornado was determined to have occurred in Warren County with max winds of 90 MPH (EF1).

Damage was first observed along Pisgah Ridge near White Road south of Richardson Road. A nearby residence had minor shingle damage, but several farm outbuildings had significant roof damage. While most of the damage had a northeast direction with the storm motion, there was evidence of rotation. One barn roof was lofted to the northeast, however there were wood planks that were impaled into the ground in the opposite direction to the southwest. Also, a nearby shed was leaning to the northwest, which was toward the tornado circulation path. The tornado continued uphill toward more farm outbuildings where a roof was lofted to the north and to the east, which was slightly offset from the northeast storm motion and evidence of rotation. Max wind speeds in this location were estimated to be 90 mph.

The tornado continued to the northeast along Richardsville Road and damage was observed at a residence. A carport awning overhang roof was damaged and lifted to the northeast, however nearby tree damage occurred to the northwest toward the center of the tornado circulation. Winds at this location were between 80 and 90 mph.

The damage continued to the northeast along James Elkins Road where several trees had snapped damage. The nearby barn had roofing material loss, and the building was shifted and leaning to the northeast after being hit by the tornado. The roof damage was laying in several different directions and the snapped tree damage had evidence of breaking and twisting with the passing of the tornado. The tornado continued across Hall Road and toward Karl Young Road where damage to a home and nearby outbuildings occurred. The homeowner mentioned that the tornado had picked up a

zero turn mower and placed it back down on top of the shed roof damage. A nearby barn was destroyed as well. Debris was lofted into a nearby field to the north and northeast of the location. Several wood plank and plywood impalements were noted facing north and west, which was continued evidence of rotation. Beyond the field north of Karl Young Road, no additional damage was observed.

During the late evening and overnight hours March 15th into March 16th, a strong upper level trough and associated cold front moved across the Ohio Valley. Ahead of the cold front, temperatures were in the 70s with dew point temperatures in the upper 50s and low 60s. This corridor of modest low-level destabilization contained between 250 and 500 J/kg of MLCAPE which was oriented immediately ahead of the surface front and the main line of showers and thunderstorms. With a corridor of 80 knot mid-level winds approaching from the west, effective bulk shear was between 40 and 50 knots for this event, creating a typical high-shear, low-CAPE setup for central Kentucky and southern Indiana. While the primary forcing mechanism was lifting along the cold front, resulting in a quasi-linear convective system, some scattered cells developed ahead of the main line of storms across western Kentucky. These storms had transient supercellular characteristics, and would go on to produce a swath of stronger winds and a few embedded tornadoes across Butler, Grayson, Breckinridge, Hardin, and Meade County. Elsewhere across Kentucky, scattered wind damage was produced by the main line of storms, with more favorably oriented segments of the line producing additional weak spin-up tornadoes. As the line of storms pushed east toward the I-75 corridor early in the morning on March 16th, there was a general weakening trend as MLCAPE values dropped to only around 100 J/kg across the Bluegrass. However, the portion of the line across southern Kentucky had access to slightly greater instability, resulting in additional instances of wind damage and a spin-up tornado in Clinton County. The line of storms eventually pushed into eastern Kentucky by around 3 AM on March 16th, with much cooler air rushing into the region behind the cold front.