Granada and Border. I'm guessing Mon-Fri they have Jon Mitchell doing the YTV weather, and then one out of Debbie, Jo, Kerrie and Steve doing the Granada/Border weather.
Does Leeds still provide weather for Tyne Tees at weekends?
Leeds provides Tyne Tees weather at all times when Bob Johnson isn't doing it, so that would include weekends as well as times when he's off as he's the only forecaster at Newcastle. I also suspect when he retires Leeds will end up doing all of Tyne Tees' weather.