Quite an unusual thing there, can’t think of the last time the weather was interrupted like that. Regardless of the slightly dubious reasoning, it was very smoothly done between Simon and Ben though (compared to say just randomly fading him out).
It's just a judgment call by a news editor. They don't know what's going to happen so have to take a risk either way. Sometimes it'll pay off sometimes it won't.
Could be worse, I've known of occasions when a news channel has ducked out of a programme for something that didn't materialise or ended a few seconds later
But then, who really cares? It's a news channel, it's ephemeral and there'll be another weather forecast along in 27 minutes
In New Zealand, the 6pm news headlines get interrupted by A TEASER FOR THE WEATHER FORECAST
God, TVNZ is terrible