June 23, 2002 Leola, South Dakota Tornadic Supercell
After 6 weeks of relatively little significant tornadic activity, ma nature produced again. Led by tour director Roger Hill, Tour 6 hit the tornado lottery sweepstakes, witnessing several incredible tornadoes from one incredible storm. Forming near a triple point (in this case the intersection of an old, modified outflow boundary left from previous convection and weak "mixing line" separating well-mixed dry boundary layer air from a deep moist boundary layer), this explosive supercell thunderstorm produced multiple classic tornadoes. Arriving only the evening before, the group had to leave Denver, Colorado at 6 am local time to make it to northeastern South Dakota in time for the show. The storm developed shortly after 6:30 pm CDT just east of Long Lake, SD just south of the North Dakota/South Dakota border. Much of the action was filmed/witnessed from northwest of Leola, SD to just northeast of Houghton, SD. The group witnessed nearly 2 hours of virtually non-stop tornadic action. A storm like this might be witnessed by a successful chaser maybe once every 2-4 years. This was a career chase for all chasers involved, including Bill Gargan (SLT co-owner) and Gene Rhoden who tirelessly led the IMAX film crew to the ends of the earth since late May looking for photogenic tornadoes in one of the worst patterns I can remember. The patience finally paid off.
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| The first tornado develops as a truncated cone condensation funnel forms above a classic fan-shaped dirt cloud. | Picking up huge amounts of dirt from plowed fields, the tornado becomes a classic "dust-dobber" with strong to occassionally violent motion visible within the circulation. | The tornado "wedges out", attaining a width of nearly 1/2 mile! | A second ghostly white tornado forms. |
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| Tornado #2 revolves around the wall cloud as a satellite vortex (to the left of the main vortex) develops. Note the "barrel cloud" updraft, clefted out by the storm-scale downdraft, producing the tornado. | As seen from the storm's backside, tornado #2 fattens as the two vortices seen in the previous image merge, with a spout-like tornado developing along the FFD gust front to the east-northeast. | Tornado #2 is now a solid dirt-choked stovepipe-shaped tornado with impressive backlighting. | The eastern edge of tornado #2, now a full-blown wedge, is visible munching over a ridgeline towards the group. |
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| Tornado #3 develops very rapidly a couple of miles west of the flabbergasted tour group. Note the spectacular wall cloud sitting atop the classically backlit barrel-shaped tornado! | A closeup of this strong tornado. The video clearly shows very dynamic motion; reminds one of the April 26, 1991 Red Rock, Oklahoma tornado. | The tornado narrows, becoming a dusty stovepipe. | Back to wedge phase. |
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| A new classic elephant trunk tornado forms! | This tornado (#4) fattens up. | A wide angle perspective gives testament to the type of storm this was; this is as good as it gets. Note the ridiculous beaver tail feeding into the north side of the low-level mesocyclone (background) with full-size tornado in progress. | Storm begins to morph to high-precipitation mode with long wet rear-flank trailing behind a forward-flank tornado mesocyclone. |
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Congrats, Kudos and Huzzahs to Silver Lining Tours Tour 6, 2002! |
| During the rope-out phase the sunlight shines through the back edge of the dryslot-eaten storm, affording the viewer an incredibly photogenic view of a narrow stovepipe tornado! | Wow! | Ropeout with towering cumulus clouds in the background. |