A high temperature warning has been issued for a dozen counties in the Republic of Ireland as some areas moved closer to officially being in a heatwave.National forecaster Met Éireann said temperatures could exceed 27C during the day with overnight temperatures staying above 15C.It said temperatures could be in the low 30s from Friday.The agency warned of water safety issues, heat stress and uncomfortable sleeping conditions as a result.The warning applies to Carlow, Kildare, Kilkenny, Laois, Limerick, Longford, Meath, Offaly, Tipperary, Waterford, Westmeath and Wexford.It will apply between 1pm on Friday and 7am on Sunday.It comes on top of a general warm weather advisory for the entire country which began on Wednesday and continues until Tuesday.The UV Index is also expected to be high t