People have been urged not to light any fires outdoors at the moment, with Coillte's communications manager saying it is highly dangerous.
Speaking on RTÉ's Drivetime, Pat Neville said there is a status red weather warning for forest fires at the moment and it is illegal to burn vegetation outdoors at present.
He said there were a number of large fires around the country in Kildare, Laois, Galway, Mayo and Leitrim over the weekend.
There was also a large fire on the Cooley Peninsula in Co Louth, which emergency services said may have started with a camp fire.
Mr Neville said that in their experience, nearly all forest and wildfire in the country have man-made sources of ignition.
He said as it is very dry, with high temperatures, even small fires can get out of control.
He added that if people see fires, they should contact the emergency services and should not approach a fire.
Dublin Fire Brigade has also urged people not to light disposable barbecues or open fires outdoors.
Don't assume that if the grass is green it's safer for a BBQ than any other vegetation at the moment.
— Dublin Fire Brigade (@DubFireBrigade) June 1, 2020
There could be layers of dead grass underneath which could lead to rapid fire spread
Let's protect our green areas 👍
🥩No BBQs
🔥No open fires
Thanks 👌#HoldFirm pic.twitter.com/BQweAYYFrO
Temperatures reached 26.9C in Newport Furnace in Co Mayo this afternoon, the hottest seen in the country so far this year.
Meanwhile, Irish Water has warned it is increasingly likely a Water Conservation Order will be required due to the prolonged dry weather.
Seperately, Northern Ireland Fire and Rescue Service has said that it has responded to 448 incidents since Friday morning, with 171 involving grass and wildfire.
In a statement NIFRS said it has been an "exceptionally busy spring period for fire crews who have worked hard in tough conditions to extinguish these wildfires."
They said that due to the recent hot weather, grass and gorse is extremely dry and appealed to members of the public not to light small fires or disposable barbecues as these can lead to significant wildfire incidents and damage to the countryside.
