Oklahoma storm had 3 extraordinary features, including a "wrong-way" tornado

Meteorologists stared at their radar screens in awe as a supercell thunderstorm performed several neat tricks.

Hours after a tornado was documented in Tillman County, Oklahoma, on April 30, meteorologists and weather enthusiasts were enthralled by a severe thunderstorm in the same county because several rare meteorological phenomena, including double tornadoes, a tornado track that looped back on itself and an "anti-cyclonic" tornado, were documented. Because the storm occurred after dark, photos and videos are few and far between, but it left its evidence on the radar.

Twin tornadoes

The radar shows the Tillman storm appeared to have two tornadoes at the same time. Having two tornadoes in the same storm, especially as one is dying and another is forming, is not rare, as supercell thunderstorms cycle their energy; in fact, two concurrent tornadoes in one storm have been documented via video on occasion, such as the twin tornadoes at Pilger, Nebraska, of June 16, 2014.

The first tornado from the Tillman storm also appeared to have looped over on its own track, which is rare but not unheard of.

Wrong-way tornado

The second tornado spawned by the Tillman storm spun the wrong way, exhibiting clockwise or "anti-cyclonic" movement. This is because the Coriolis Effect, which dictates rotation at the size of a tornado, is never 100 percent effective. It is estimated that only 1 to 2 percent of tornadoes rotate clockwise.

The radar showed winds toward the radar on the south side of the storm, with winds away from the radar on the north side, meaning that the tornado was spinning clockwise. The two tornadoes from the Tillman storm may have even experienced the Fujiwhara effect, spinning around each other.

A towering, rotating storm

The Tillman thunderstorm also appeared to have a complete cyclonic structure as high as 18,000 feet, which is rarely seen in radar data. Typically, tornadoes twist below the storm's base, which is also rotating but far beneath the top of the storm.

Tornadoes are rated on the Fujita scale based on a post-storm estimate of damage, and tornadoes in rural areas can be underestimated because there are no structures to indicate damage. Very little damage was done by these rural storms. The NWS said "this [first] tornado produced EF1 damage, although it was likely much stronger." The second anti-cyclonic tornado was also rated EF1.

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