Flood risk is the biggest immediate concern weatherwise, given that the ground is already saturated from persistent rainfall in recent days.
With snow likely later today and rainfall of 20 to 25mm expected to fall overnight, river levels could rise significantly.
Met Eireann is warning that this could lead to surface and river flooding.
As a result, a status yellow rainfall warning has been issued for Donegal, all of Connacht, Cavan, Monaghan, Longford, Louth, Offaly, Westmeath, Meath, Clare and Tipperary. The warning applies from 8.00pm on Sunday to 8.00am on Monday.
Today will however feel calmer than in recent weeks, with gusty northwest winds easing and backing southeast by evening. Early rain will ease in the afternoon, with sunny spells and scattered showers, though wintry showers and heavy rain will return by evening.
Today's temperatures will be around 7°C but it will feel much cooler.
As overnight sleet turns to rain, temperatures will climb to 10°C or 11°C, with winds veering from southeast to southwest by morning.
Monday will see a return to strong, southwest to westerly winds, though they should ease by Monday evening, with temperatures dropping to 1°C to 2°C during Monday night.
Tuesday will be very cold with fresh southwest to west wind and wintry showers, worst in coastal areas.
Wednesday will not be quite as cold, with wintry showers giving way to rain overnight, with mild but wet weather on Thursday.
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