My surname is one of confusion to some of my fellow DODers across the waters, so let me school you.
It's prounced "Ray" - like the ray of sunshine that I am. Such is the history of the surname that it has spawned many the variation:
Rae fairly rare: Belfast area, Dublin etc. Scottish, a Borders name now widespread in Scotland. See Rea and Ray. SS.
Ray Quite numerous: Dublin, Down etc. English, denoting "king" - some confusion with Scottish Rae and Irish Rea, q.v.
>> Rea << (1) numerous: Belfast and E Ulster. Scottish, more usually Rae, associated with the Borders, but MacLysaght says it is sometimes abbreviation of Mac Crea, q.v. (2) fairly numerous: Limerick->> Cork<< -Tipperary, South East. Ir. Ó Riabhaigh, riabhach, striped, brindled. Often pronounced "ray" - see Castlerea. MIF & SI.
Reagh Very rare: Portrush (Antrim). Ir. Riabhach (striped). Epithet which displaced surname. See Rea.
Reay rare: Louth, Belfast etc. See Rea.
Rhea a form of Rea formerly in Donegal. The name does not appear in current telephone directories, but has been previously recorded.
Wray numerous: Derry-Tyrone and Ulster generally. English settlers from Yorkshire in 16 cent; a locative name, it may stand, in some cases, for Rea, q.v.
I don't actually mind how people pronounce it btw (Ree, Raya, whatver), just say it like you mean it, solider!