Alarmism for the sake of it?

We keep hearing stories from the weatherpersons about how the temperature is going down to -11 deg.C and everywhere is already freezing as a blast of cold air heads in from Europe (source of everything bad?) over the next few days. But today is noticeably warmer than yesterday; or to be accurate, noticeably less cold, and we didn’t get the huge great frost, which the BBC weatherpersons threatened us with yesterday. So why are they trying to scare us?