The fog that has started to form in the south of the warning area will become more widespread during Tuesday evening and night.

Fog is likely to become dense in places with visibility less than 100 metres, which may lead to some travel disruption and slower journey times. Fog will clear in the south and west of the area during Wednesday morning, but may persist until early afternoon in the north and east.

What to expect

Slower journey times with delays to bus and train services possible
There is a chance of delays or cancellations to flights

Regions and local authorities affected

Denbighshire
Flintshire
Monmouthshire
Powys
Wrexham