We are in the middle of another very mild spell of weather. Currently my CET estimate stands at 12.62C which is 0.3C below Hadley.
Based on current output the CET could reach 12.95C by the 25th. After that the models currently show the warmth leaking away although it still stays above average until the end of the month. Currently my estimate for the finishing CET is 12.57C.
However, if the warmth did stick around until the end of the month then a CET of 13C is quite possible. This is not that unusual in recent times as we have seen 13C+ three times since 2000, the warmest being 13.3C in 2001. There is no realistic chance of beating that this year unless something remarkable happens.