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National Service Meteorologists surveyed storm damage in western Jefferson County, and found that the damage was consistent with a tornado. There were three separate notable increases in damage severity and/or density, likely indicating that the tornado`s funnel had a skipping/cycling characteristic as it swayed from less to more intense.
The tornado touched down along 5th Street North, between Highway 11 and Avenue A, where damage ranged from broken large limbs to uprooted and snapped trees. The tornado then traveled northeast with a long swath of damage centered along a track generally between Interstate 20/59 and Highway 11. Aside from continued uprooting of trees and downing of limbs, the first notable damage occurred just west of Western Hills Mall, where there was hefty damage to an Express Oil Change, Alabama ABC store, and mini strip mall, along Dr. M.L.K. Boulevard. Damage at this location was likely the result of a short-lived, concentrated vortex, with a track around 300 yards in length and EF-1 intensity. Beyond this point, damage fell into EF-0.
The tornado continued knocking down trees as it moved northeast, with some trees falling onto homes, resulting in severe roof damage. Tornadic winds also caused minor to moderate roof damage ranging from missing shingles to sections of roof damaged or blown off, especially in neighborhoods adjacent to Miles College (to the south and northeast). Given a noticeable increase in damage density, it`s possible that the tornado briefly intensified in this area, over the course of roughly a 700 yard path. While there was an obvious increase in the amount of uprooted trees, there was a large contribution from shallow root systems and especially saturated soil from several-day`s rain; thus, given a lack of notable wind-driven damage to homes (which held in EF-0, characteristic of shingle and roof trim damage), the overall damage pattern didn`t tip the scale for a small corridor of EF-1 rating.
Next, the tornado neared and crossed Interstate 20/59 where the extent of damage backed off, though some minor structural damage was done to the Tire Tech car bay, and Freeway Honda. Windows were also blown out of a few cars at Honda dealership. An increase in the number of uprooted trees was again observed surrounding Tuxedo Park on the north side of Interstate 20/59, along with roof damage to a few homes. Tornado damage became very sporadic and increasingly less significant as the tornado neared Bankhead Highway, dissipating near the CSX Transportation railways adjacent to Pratt Highway.
Statement on EF Rating:
The Fairfield tornado was given a preliminary rating of EF-2, though was later downgraded to EF-1 intensity after a detailed damage survey was conducted. Several factors led to the downgrade, including: extent of damage to buildings and contributing roles from wind entry points and/or characteristics of construction; indications from surrounding damage. These considerations are outlined below.
A panoramic shot of the KFC restaurant and Express Oil Change (see first damage picture below) revealed a noticeable difference in degree of damage to the two structures. It was determined that a total of six large bay doors on the Express Oil Change played a large role in the structural compromise of the building. These doors served as an entry point for tornadic winds to lift and shift the entire roof, which then resulted in several points of wall failure. If tornadic winds were directly responsible for the collapsed portions of walls at the Express Oil Change versus assistance from the six wind entry points, then there would have been a higher level of damage to the KFC restaurant. Taking into account the most notable damage between the two buildings, a designation of EF-1 intensity was assigned.
Immediately behind the KFC and Express Oil Change sat an ABC store. While there was a very dramatic-looking and near-complete destruction of the structure, aside from a few remaining interior walls, a close inspection suggested construction characteristics played a large role in the demise of the structure. This included the type of framing and wall-to-foundation fastening. It was determined that EF-1 wind speeds were strong enough to cause the extent of damage observed at the ABC store. Just to the north of the ABC store, damage to a mini strip mall and the first few units of a housing complex also matched up to a tornado of EF-1 intensity. In other words, while an EF-2 tornado probably would have resulted in similar damage to the ABC store, we looked for lower wind speeds capable of producing this damage, considering the nature of construction and level of damage to the aforementioned surrounding structures.
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