Abertawe Bro Morgannwg University Health Board says it has seen a high number of emergency admissions, and its A&E departments are extremely busy and under pressure.
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Windy with possible gales in exposure.
We've been to meet brother and sister Theo and Robin who go to one of Wales's newest schools to see what a typical day is like for them.
It will remain breezy with further blustery and at times thundery showers.