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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After a dry end to the day, there'll be a few showers this evening Winds getting stronger overnight.
If you missed tonight's episode of Wales This Week, Test Tube Triumph, you can now catch up here
Jean Davies said her life had become "intolerable". Her daughter Bronwen speaks to ITV News about the decision.