Unfortunately not, 'quite bad' is not the same as extreme weather and no severe travel alert had been issued. The amber alert is about thinking ahead and avoiding unnecessary travel, it is not an instruction to not travel.
It's not covered, the definition of adverse weather is:
Adverse Weather means extreme weather where a severe travel alert has been issued on the day of the Event by either the Local Authority or Government of the Country in which the Event is taking place preventing your ability to travel to...