It's May 1st which means it's Bealtaine or Beltane in the Celtic Nations.
According to the Irish calendar, summer begins on May 1st and ends on July 31st. This relates specifically to the ancient Celtic Festivals of old when the first of May or Mayday began with the celebration of Bealtaine (pronounced phonetically as "Bee-yowl-tan-eh"), which officially marked the beginning of summertime.
Directly translated Bealtaine means "mouth of fire" coming from the Irish Gaelic Béal (mouth) and tine (fire) referring to the Sun as its light and heat rise further and further towards the Summer Solstice.
For our ancestors, this early summer season initiated the release of the cattle to the summer pastures. It was important that certain rituals were performed to protect them before the journey and so they were driven between two fires where the smoke not only eliminated any parasites on their hides, but was seen to offer protection from illness and theft.
In tandem, the drovers and the whole community followed suit, calling in a healthy growing season for them as well. Those in the northwest would make pilgrimage to the great Beltany Stone Circle in Co. Donegal, which is aligned with the rising sun at Bealtaine as it appears to "sit" on the peak of the only carved stone.