The Welsh Ambulance Service says it is "very concerned at the handover delays that have been experienced recently".
It is "concerned that pressure across all hospitals in Wales has a direct impact on the ambulance response that is able to be provided to patients who call 999 for our help."
"Ambulance crews continue to provide clinical care for patients as they wait to be admitted into hospital and we provide ambulance clinicians, where possible, to care for patients in emergency departments to support the nursing and medical staff in hospitals."
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There will be some patchy rain but many areas will be dry for much of the time.