Tornadus-T never runs 252 HP, so it is even OHKOed by 0 SpA Zapdos's Tbolt, which does 105.26 - 125% to Naive Tornadus-T (Life Orb Tornadus-T) and 90.3 - 107.02% to Timid Tornadus-T (Choice Specs Tornadus-T). Scarf Zapdos is a good check to Tornadus-T because it can switch into him once or twice, but SR will wear him down really fast. 252 HP / 252 SpD Zapdos with a Calm nature is one of the best Tornadus-T counters out there because it isn't 2hkoed even after SR by anything, and has Roost to last long.