A long cold winter?

What will this winter be like? A much discussed question during the autumn months. Also one which is very difficult to answer. We seem to have passed this years Northern Hemisphere snow and ice cover minimum. As shown in the first figure, this seems to have happened around the end of August.

If we have a look at yesterdays snow cover we can see that already the winter snows have started to appear in Alaska and North East Siberia. If we compare with the snow cover on the same date in 2010 and 2009, we can see that this year we are already a fair bit ahead. There seems to be some evidence to suggest that early snow cover is more likely to lead to Northern Blocking, and thus a cold winter for Britain. Winter is obviously a long way off, and a lot can change between now and then, but things seem to have got off to good start.

12th September 2011

12th September 2010

12th September 2009