David BaleMuch of Norfolk has been hit by wintry snow showers today with more expected later tonight and into tomorrow morningDavid Bale

Much of Norfolk has been hit by wintry snow showers today with more expected later tonight and into tomorrow morning.

The Met Office has issued an early warning and said travel networks may be affected by snow tomorrow.

Up to 20cm of snow could fall in some parts of East Anglia, with gale-force winds causing drifts.

Forecasters at Weatherquest at the UEA said sleety showers were expected in Norfolk later today followed by longer periods of sleet and snow overnight.

Temperatures in Norfolk will remain quite cold at 3C today dropping to -1C overnight, and it will also be pretty windy.

East Anglia and the south east are likely to see further snow showers tomorrow, although conditions are expected to ease, before more snow on the weekend.

Road users are being urges not to travel in severe weather unless the journey is essential, and to check local and national weather forecasts before setting out.

Conditions are expected to be at their worst during the Friday morning rush hour.

BBC weather forecaster Philip Avery said the amount of snow forecast is similar to the amount that fell in 2003, trapping thousands of drivers on the M11 and M25.

He said: 'This is going to affect the M25, M26 and M11 in places. The Highways Agency, given the early warning, should be on the case... but it's the first dump of the season and we seem to struggle on these occasions.'

However the Met Office said it was too early to say whether there would be a white Christmas.

A Met Office spokesman said: 'Current indications show an ongoing battle between the colder air currently over the UK and milder air pushing in from the west. As a result the forecast for Christmas Day is still too close to call.'