PACK the mac.
Don't be deceived by today's summery weather. It won't last the weekend.
Temperatures today, especially inland, will be very high for this time of year, up to 22 Celsius, and the day will be sunny.
Tomorrow will probably continue dry in most places, according to the Met Office, but it will be cooler because there will be a lot of cloud about, and the pressure will be falling.
This will result in rain spreading into most areas on Sunday, which will worsen on Monday, when the rain will be widespread.
Monday will be "a fairly miserable day," and temperatures will continue to fall, barely reaching normal by Tuesday.
The weather is unlikely to deter the crowds expected to descend on Galway for the Budweiser American Music Festival, which opened last night with Nanci Griffith. It continues tonight with blues guitarist Peter Green.
Over the weekend it will feature Chick Prophet along with Irish singer Eleanor McEvoy and, on Monday, Mary Black.
There will be plays, music and exhibitions in Newbridge, Co Kildare, at its Bealtaine Arts Festival, which is celebrating a recent grant of £400,000 from the Department of Arts, Culture and the Gaeltacht for an arts and cultural centre.
The two main sporting events over the weekend are both on Sunday.
The FAI Senior Cup Final between Derry City and Shelbourne takes place in Dalymount Park in Dublin. Pairc Ui Cuiv in Cork sees the National Football League final between Cork and Kerry.
On Monday famine marchers will brave the rain to raise money for Gorta and the Big Issues. Famine marches are taking place around Dublin, in Malahide, Dun Laoghaire, Oldcastle, Co Meath, Arklow and other venues.
There will also be an increase in people leaving the State for the weekend, compared with last year.
Traffic in and out of Dublin Airport will be up 12 per cent on last year, with 115,000 passengers. Shannon will see a 9 per cent increase, with 23,000 passengers, and Cork is up 5 per cent, to 13,700.
At least some of this may be explained by the introduction of new services. This weekend sees the start of Ryanair's flights to Brussels, Paris and Bristol, the inauguration of a Cityjet service to Paris and of a Finnair service to Helsinki/Stockholm.
The ferry companies are also very busy Stena Sealink will carry 5,000 cars and 28,000 passengers. Irish Ferries will carry 4,000 cars and 23,000 passengers to and from Britain, and 1,300 cars and 4,000 passengers on its Rosslare France route.