Update - 2.12pm: The Air Corps says it is tackling wildfires in six counties across the country.
Helicopters have dropped around 300,000 litres of water in Dublin, Wicklow, Limerick, Cork, Tipperary and Offaly.
Conditions at the Slieve Bloom mountains on the Laois-Offaly border are said to be very dangerous.
Drivers travelling on the M7 are being warned that visibility is poor due to thick smoke in the area.
Speaking to Midlands 103, retired District Manager with Coillte Richard Whelan says the fire is moving fast;
Mr Whelan said: "It's burning right through the forest, but also it's running up the trees, 40 to 50 feet and that is very dangerous and very hot conditions.
"Also, last night when I was up there, it was circling as well, so it is extremely dangerous for anybody to go in there."
Over the last 24 hours the Air Corps have been involved in aerial firefighting operations in Dublin, Wicklow, Limerick and Cork supporting the extremely hard working units on the ground. Stay safe this weekend. #strengthenthenation @DubFireBrigade pic.twitter.com/UuEOjeIXgy— Irish Air Corps (@IrishAirCorps) June 29, 2018
12.11pm: Here's what you can do to prevent forest fires as Coillte tackles blazes in three counties
Coillte is re-iterating its appeal for people to be extra vigilant about the dangers of wildfires as the dry weather continues into next week.
Coillte is fighting a number of fires nationwide today.
The State-owned commercial forestry company has fire patrols for every forest, have built fire breaks, and have specialised equipment in high-risk areas.
They have recommended five things to prevent forest fires.
9.47am: Dublin Fire Brigade believe FIVE fires in Dublin park last night were started maliciously
Dublin Fire Brigade has said five different fires in Dublin's Bushy Park last night may have been started maliciously.
Crews attended the scene in Terenure yesterday while also attending early morning gorse fires in Ticknock, Citywest and Glencullen.
A 'Condition Red' fire alert remains in place because vegetation is still very dry.
Dublin Fire Brigade is warning against lighting open fires or barbeques.
Over 2 hours, Rathfarnham stn firefighters have extinguished 5 different fires in Bushy Park tonight, believed to have been started maliciously. Red fire warning ⚠ still in place, vegetation is very dry #Dublin #fire pic.twitter.com/rPQCz0wd2E— Dublin Fire Brigade (@DubFireBrigade) July 4, 2018