The Met Office upgrades its earlier forecasts.
The warning is in force from 3 pm on Thursday 9 March until Friday at noon.
The warning states:
Snow is expected to develop over northern England on Thursday morning, becoming persistent through the afternoon and overnight into early Friday morning before slowly easing.
Residual impacts from snowfall are expected to persist through Friday morning. 10-20 cm of snow is expected to fall quite widely, with some places seeing 30-40 cm. Strong easterly winds are expected to accompany this snow, leading to blizzards and drifting of lying snow.