A low pressure system is moving north of the UK towards Iceland, bringing unsettled conditions (though with no intense rainfall) especially in Scotland and Northern England.
During the the night some rainfall is expected on Western Scotland and northern England (mainly Pennines), with moderate rain on the mountanous areas, bright conditions elsewhere. During the afternoon, showers are expected in Wales, Scotland and northern England, with bright conditions on the east, and from the evening some showers are expected also in the south east.
Some snow it’s expected still on the highlands during Wednesday evening.
The minimum temperatures will decrease especially in England due to bright conditions (0-5 °C mostly everywhere), with negative values (-1,-3 °C) in Wales, highlands and northern England. During the day, milder temperatures are expected especially on southern England (10-13 °C) and Wales (8-13°C), instead still cold in northern England and Scotland (4-10 °C).
Finally, the winds will be southerly and light mostly everywhere, with moderate winds in the evening in eastern England.
Synoptic chart valid for 31/10/2018. Met Office.