The former Republic of Ireland goalkeeper joined North End in October but will now make the switch to Roy Hodgson’s Eagles, who are currently 14th in the top flight.
Kiely has previously worked under Hodgson at West Brom.
In a statement on their official website, Preston said: “In an interim period Academy goalkeeping coach Jack Cudworth will move up to work with the first team goalkeepers at the club, whilst manager Alex Neil decides on the long term plan in that area of the coaching staff.
“The club would like to thank Dean for his contribution in his time with the club and wish him all the best in his future career.”
Cardiff remain unhappy with Derby's decision to postpone Sunday's Sky Bet Championship game at Pride Park.
Dundee United boss Csaba Laszlo has been left hoping for St Mirren to slip up in the race to seal promotion to the Ladbrokes Premiership.
Crewe will consider starting Chris Dagnall when they host Forest Green on Tuesday.