2008 APRIL 17: WILLOW PARK, TEXAS
Tornado ~4m NNE of Willow Park, Texas @ 0022z, observed from ~3 miles west
I observed the northernmost supercell first, taking a position near
Chico, Texas, but I was blocked from further approach by Lake
Bridgeport. The storm showed disorganized lowerings but became outflow
dominant. When rain from the southern storm contaminated the updraft
region, I dropped south toward Weatherford. I noticed that even as my
old storm became more linear, it continued to show strong low level
rotation in the "notch" features that developed along the forward flank.
The southern cell showed a similar pattern.
Near Azle, I turned on FM 730 with a southwesterly tack to skirt the core. While I was flanking, Parker County spotters reported tennis balls and baseballs on the north side of Weatherford, with a lone softball report as well. This was an important development as the hail effectively pinned the spotters along and south of the interstate. I turned briefly east and then south on FM 3325 to approximately seven miles east of Lake Weatherford. Another lake. The updraft was to my west and growing obscured as the old long-lived hook folded into more of a notch. Though I haven't checked archived data, I believe the storm retained supercellular characteristics at this time, around 7:15 PM.
Just north of the FM 3325/White Settlement Road intersection, a large wallcloud came into view, about four miles to my west. This feature was connected to the base of the storm. In the photo above, a forward flank cloud deck in the immediate upper foreground hides the real base. That cloud deck is not the distant storm's base. Nor is the blocky condensation from which the tornado extends the updraft base; that's the wallcloud. This configuration was more apparent in later views from White Settlement itself, when the storm was closer and base and wallcloud both became visible. At the time, it was confusing. I stopped on the crest of a private driveway as cascading "sheets" of condensation moved from north to south into the wallcloud. The primary "core" of the wallcloud, on the left side, assumed a cylindrical shape and began to rotate.
An RFD cut appeared on the southern edge and a funnel extended rapidly. I wasn't confident about what I was seeing, but thought I should keep shooting stills and sort it out later. As I mentioned, I put the time of this around 7:22 PM, and it lasted no more than ten seconds. I've guessed it was approximately four miles NNEof Willow Park, Texas or eight miles ENE of Weatherford.