All bets covered

I was reading a newspaper story in which researchers; also in the Manchester area; were assuring us that the UK gets nearly twice as many tornadoes as the US per 10,000 square kilometres.
    First it was ‘tornadoes’ and later in the article, it was ‘tornados’.
    I assumed from this that the AI spellchecker had been having a day off as well as the human one; if there still is one!