LONDON, ENGLAND - DECEMBER 12:  A man walks his dog through the early morning frost in Regents Park on December 12, 2012 in London, England. Forecasters have warned that the UK could experience the coldest day of the year so far today, with temperatures dropping as low as -14C, bringing widespread ice, harsh frosts and freezing fog. Travel disruption is expected with warnings for heavy snow in some parts of the country.  (Photo by Dan Kitwood/Getty Images)