Who says we can't have a cold winter after a 20 year period
(1987-2006) of predominantly mild winters, It's happened before.

Based on Central England Temperatures, from 1896 to 1916 there were no
winters with an average CET below 3.0c. The average winter
temperature from 1896 to 1916 was 4.4c

YEAR WINTER
1895 1.2 Excluded from avg
1896 4.4
1897 3.8
1898 5.4
1899 5.8
1900 3.1
1901 4.3
1902 3.2
1903 5.3
1904 3.6
1905 4.2
1906 4.4
1907 3.1
1908 4.1
1909 3.4
1910 4.2
1911 5.0
1912 5.1
1913 5.3
1914 5.2
1915 4.3
1916 5.5
1917 1.5 Excluded from avg

Average 4.4

Compared to the period 1987 to 2006, also there hasn't been a winter
with a CET below 3.0c. The average winter temperature from 1987 to
2006 has been 4.9c.

YEAR WINTER
1986 2.9 Excluded from avg
1987 3.5
1988 5.3
1989 6.5
1990 6.2
1991 3.0
1992 4.6
1993 4.7
1994 4.7
1995 5.9
1996 3.0
1997 4.0
1998 6.1
1999 5.4
2000 5.4
2001 4.5
2002 5.4
2003 4.7
2004 5.1
2005 5.2
2006 4.1

Average 4.9

Never say never.

Just because we haven't had a cold winter since 1986, does not mean we
will not have a cold winter again (even with climate change).

http://www.metoffice.gov.uk/research...HadCET_act.txt

Winter classed as Dec of previous year, Jan & Feb