Smiths Triumph’s Jake Dixon topped the Motorpoint British Supersport free practice sessions, after handling the tricky conditions expertly.
Dixon ended the first session in second behind Irwin but the second session later in the afternoon was far quicker, with Dixon posting a 1’37.829.
Just shy of a second behind Dixon was Gearlink Kawasaki’s Glenn Irwin with Profile Triumph’s Sam Hornsey a further two and a half seconds back in third.
Gearlink Kawasaki’s Luke Hedger ended the combined sessions fourth quickest ahead of Supersport rookie Joe Francis and Supersport veteran Ben Wilson.
South African Bjorn Estment was the quickest of the EVO riders in seventh, 4.1 seconds behind Dixon’s pace.
Floridian James Rispoli was eighth quickest in the miserable conditions, with Appleyard Macadam’s Danny Webb and the recently crowned British Supersport champion, Luke Stapleford, rounding out the top ten.