The Fire Brigade Union are walking out for the second time in a week due to rows over pensions. The government wants firefighters to work until they are 60.
Fire departments across Wales have issued safety warnings in light of bonfire night and are asking people to be careful with fireworks.
Trained auxiliary firefighters will step in to cover duty during the industrial action. The FBU will picket from 06:00 and 08:00 this morning.
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Fire crews say the Pandy Tudur residents have been safely evacuated, but six have been taken to hospital for check ups.
The calm after the storm! We'll see sunny spells and blue skies at times with a few showers falling as snow over the hills.
Last month saw the highest number of patients visiting A&E for any December on record in Wales, new figures show.