The MET office warning for snow begins at 00.05am on Friday and will remain in place until 11:59pm.

Motorists are being advised to expect disruption and to allow extra time for their journeys.

Outbreaks of sleet and snow are due to arrive in Co Fermanagh and Co Armagh on Thursday evening. Heavier rain will spread northwards on Thursday night, and will turn increasingly to snow later into Friday.

Heavy and persistent snowfall will develop across many other areas, with accumulations of 30cm or more likely across the hills in Co Antrim and Co Down.

Taking into account the strong to gale force winds, some atrocious conditions with drifting and blizzards are expected for many upland areas in particular.

Up to 10cm of snow is possible at low-level, with rain and sleet towards the east coast causing a risk of localised flooding.

"The public should be aware of the likelihood of a spell of difficult and disruptive wintry weather, with impacts on travel and, perhaps, on power supplies," a MET Office spokesperson said.

Regional Development Minister, Danny Kennedy, said: "We have 300 staff and around 130 gritters on standby to salt main roads to help drivers to cope with wintry conditions.

"However, motorists and public transport users should keep an eye on the forecast and be prepared for disruption to their daily commute, allowing plenty of time when planning a journey

"During such Met Office warnings it is advised to only travel if your journey is absolutely necessary," he added.

The Minister warned: "Even with the most careful and thorough planning, ice or snow-free roads can never be guaranteed. Motorists need to take extra care during wintry conditions.

"The best advice is in the Highway Code - drive with care even if roads have been salted, be prepared for road conditions changing over short distances and take care when overtaking gritters."

George Best Belfast City Airport is advising passengers to check the status of their flight before travelling.

Passengers are being advised to contact their airline or visit www.belfastcityairport.com where the latest flight information will be available.

Northern Ireland Electricity has warned of a possibility of damage to the electricity network, especially in exposed locations.

A statement from the major power firm said: "NIE has initiated an escalation plan and has emergency crews, engineers and call handlers on stand-by.

"We would like to remind customers that if they do lose electricity supplies they should contact the NIE Customer Helpline on 08457 643 643 or report the fault online at www.nie.co.uk."

MET Éireann has also issued a severe weather warning for snow and ice in the Ulster counties Cavan, Monaghan and Donegal.

The orange 'Be Prepared' warning is valid from Thursday at 9pm and lasts through to the early hours of Sunday morning,

A MET Éireann statement said: "Rain, sleet and snow mix will give some lying snow accumulations especially on hills but also at some lower levels. There will be blizzards and drifting in the strong winds."

There is also a rain warning in place for the rest of the country with widespread heavy showers expecting to cause spot flooding.