After an unseasonably warm September, temperatures will drop off over the coming days with cooler nights and early mornings to be expected.
Met Éireann says the coming days will be "noticeably cooler and unsettled" as nighttime temperatures fall to around 5C which is average for this time of year. Heavy showers and rain spells can also be expected.
Forecasters are predicting the cooler weather to set in from Sunday night with the week ahead feeling much more autumnal.
Alan O'Reilly from Carlow Weather says the change will be "a shock to the system" after the unusual warm spell we've been having.
"Temperatures are dropping down to 4C or 5C so it is certainly going to be much cooler at night and a much cooler start to the day as temperatures drop back," he said.
The start of the week will be much cooler and fresher with a mix of sunny spells and heavy showers across the country, with a risk of thunderstorms in parts.
Temperatures will return to around normal for this time of year with highs of 12C to 15C during the day, dropping to as low as 6C at night.
Met Éireann says Tuesday will be a wet day overall with heavy rain expected across the country and thundery downpours in parts.
Temperatures are expected to be around 11C to 14C, dropping to between 5C to 8C at night.
The middle of the week be much drier than the previous few days with strong sunny spells and a few scattered showers in northern parts.
Temperatures between 10C and 13C are to be expected, getting cooler at night with outbreaks of rain and blustery winds.