The YEP reported earlier today that a yellow warning had been issued for Leeds with up to nine hours of snow forecast.
This has now been upgraded to an amber warning with 12 hours of snow fall now expected and 'heavy snow' for seven hours in the Leeds area.
The yellow warning for snow runs from 3am until 3pm on Friday and the amber warning runs from 4am until 11am.
The Met Office amber warning says: "A spell of heavy snow is likely over parts of northern England on Friday morning.
"Travel delays on roads are likely, stranding some vehicles and passengers.
"Some delays and cancellations to rail and air travel are likely.
"There is a possibility that some rural communities could become temporarily cut off. Power cuts may also occur."
And it will be icy, with temperatures not climbing above freezing until 11am. Met Office forecasters say the wind-chill will make it feel like -5C throughout the morning.
The rest of today is expected to be clear but cold with winds picking up this evening before temperatures fall sharply overnight.
Ex-NASA engineer reveals quickest way to defrost windscreensFull Met Office forecast for Leeds:
It will be a cold and crisp start, with a widespread frost. A fine and largely sunny day then follows, with the strong winds gradually easing. However it will remain cold. Maximum temperature 4C.
Clear skies, and light winds will lead to temperatures quickly falling after dusk. A very cold night is then expected, with a widespread sharp frost. Minimum temperature -5 C.
Cold, bright start. However cloud soon thickens from the southwest, with rain and snow spreading northeast. Snow accumulations are expected across the hills, and perhaps also to some lower levels. Maximum temperature 5C.
Outlook for Saturday to Monday:
Cold, icy early Saturday, before further rain spreads northeast, clearing to less cold but breezy conditions. Unsettled and milder Sunday and Monday, with sunshine and blustery showers.