Met Éireann has issued a Status Yellow snow and ice warning for the entire country.
It comes into effect at 10pm on Wednesday and will remain valid until 12pm on Thursday.
Irish Water have been branded a "disgrace" and "not fit for purpose" following revelations raw sewage is seeping from manholes in a Longford housing estate out onto a main road.
They warn that "blustery squally showers of hail, sleet and snow with icy stretches on untreated surfaces will lead to hazardous driving conditions on Wednesday night and Thursday morning."
They also say that some thunder and lightning is expected too.
Met Éireann's outlook beyond that says that it will be drier for Friday and Saturday before turning wet for a time later this weekend.
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