Wintry showers that are set to stay all day have started this rush hour.
The Met Office said the snow will occasionally turn to hail or sleet. There will be bright spells, but it will be mainly cloudy with a very cold breeze.
There are currently no school closures, but heavy traffic is causing delays on the motorways.
There are long delays of 50 minutes, on the M62 eastbound from J22 at Rishworth Moor to J27 at Gildersome.
Traffic is also heavy on the M1 northbound at J39 at Durkar.