To celebrate Science Week, the RTÉ Weather team are sharing some fun facts about - you guessed it - the weather! In the video above, Michelle Dillon introduces us to the polar jet stream.
As Audrey McGrath previously explained, Ireland is located near the polar front - the boundary between the cold air in the north and the warm tropical air to the south.
High above the polar front, we have the polar jet stream, which is a ribbon of very fast flowing air that can reach speeds of up to 300 kilometres per hour.
Situated between nine and twelve kilometres in altitude, the jet stream is thousands of miles long and hundreds of miles wide.
Aircraft can take advantage of the jet stream to make the flight from America to Ireland go that little bit quicker! However, it can also involve a little turbulence at times.