Roger's SkyPix

The Majestic Supercell

Prelude to an October Tornado

Prelude to an October Tornado

Yes, the date is right; this was in the fall! Striking, banded supercell structure on display with a long tail cloud extending off to the right. Can you pick out the spot at left where the tornado is about to develop? The innocuous-looking little wall cloud at lower left was actually rotating rapidly. Below, a funnel cloud formed under the small wall cloud, dangling ominously as the main updraft and mesocyclone moved closer. Note the clear slot cutting from right to left through the cloud deck W and NW of the funnel (to the right of the utility pole). Clear slots like that often (but not always!) are precursors to a tornado. Under the funnel, circulating winds were probably already reaching the ground, but not yet strong enough to stir up noticeable debris. Closer observers began reporting rotating dust on the ground within a minute after this photo. Soon a mature, 14-minute, well-developed tornado would cruise across the Oklahoma prairie.

5 WSW Dover OK (4 Oct 98), looking WSW

Bulbous Funnel from Dover OK Supercell