A couple of temperatures from the log book for mid-December 05:
Thistlegorm - 24c
Abu Nuhas - 25c
Bluff point (Small Gubal) - 22c
Kingston wreck - 24c
Ras Mo - 24c
Still pretty warm underwater in December: even for a nesh girl (5mm + hood was fine for me). The rib ride back to the boat from bluff point was a bit chilly though! I found getting dekitted in the wind was the worst aspect (hasn't put me off going to the Brothers this year for Xmas!

)
Enjoy!