Monday will be a very warm day, with a mix of cloud and sunny spells. Rain and drizzle will dominate Connacht and Ulster before good spells of sunshine become more widespread from the south through the afternoon. While it should stay dry for most, a few sharp thundery showers are possible in the south and east with highs of 22C to 27C in general. 

It will stay mild, dry and clear on Monday night with some fog patches and temperatures of 12C to 17C. 

Tuesday will stay dry, with long spells of sunshine. However, it will be cloudier at times with highs of 22C to 28C or 29C, with some parts of Cork City reaching 30C. It will be warmest in the south and east. 

It will be dry and mostly clear on Tuesday night with some light rain or drizzle in the northwest. Some southern and eastern areas will stay clear with temperatures not falling below 13C. 

Wednesday will be a rather cloudy morning, with a few spots of light rain or drizzle before it breaks up through the day with spells of sunshine and some showers in the northwest and west. Highs of 22C to 29C are set for the day, with the warmest in the southern half of the country. 

It will be a mix of cloud and clear spells on Wednesday night, staying dry for most with some showers possible for the northwest. Temperatures will not fall below 13C in the north and 18C/19C in the southwest. 

Met Éireann says Thursday will be a hot day with mostly dry and sunny conditions. A few showers may break out through the day, potentially heavy and thundery, especially in the northwest in the evening. Highs of 25C to 31C are set for the day before it starts to turn cloudy from the south overnight, with patchy rain and drizzle. Night-time temperatures will not fall below 15C. 

Friday will see a mix of cloud and sunshine with showery rain, heaviest and most persistent for the western half of the country. Highs of 19C to 25C are set, with the warmest conditions in the east. 

It comes as authorities in France have placed more than a third of the country under a red heat alert, cancelled some outdoor sports events and restricted alcohol consumption at the nationwide Fête de la Musique event amid a brutal heatwave forecast to push temperatures above 40C.

Level 1 or 2 heat alerts were issued on Sunday for about 53 million people, just over 75% of the population. A record 35 of the country’s 96 mainland departments were put on danger-to-life red alert, with another 45 under an orange warning.

France’s ecology minister, Mathieu Lefèvre, said on Sunday that 14 more departments would be on red alert on Monday. “We do not see temperatures falling before the end of the week,” he said, demanding “great prudence and a great many precautions”.

- Additional reporting from the Guardian