It could be northern regions that are next affected by tornados.  That’s the latest news from the Radio Network’s weather watch centre.  Head Weather Analyst Philip Duncan says thunderstorms are forming off shore and places north of the Bombay’s should be on alert.  “While we can’t predict exactly where they’ll form we can say we have all the right ingredients for them”.  Duncan says the twisters over Taranaki formed where warm air from the north collided with cold air from the south.  “This afternoon that zone has shifted to Northland, Auckland and Waikato”.