Winter '12 / '13 - White Christmas

White Christmas in the US is defined as 1" on-the-ground on 25-DEC.  The criteria are different in other countries.

The probability of an event is determined by dividing the number of times something happened in the past by the number of times it could have happened.

If there was a white Christmas five times over 20 years...the probability is 25% in any given year.

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Folklore predictions...
- A green Christmas; a white Easter.

- If there's thunder during Christmas week...
The Winter will be anything but meek.

- The nearer the New Moon to Christmas Day...the harder the Winter.
[ed:  New moon 13-DEC-12]

- If Christmas day be bright and clear
There’ll be two winters in the year.

- Thunder in December presages fine weather.

- Like in December like all the year long.