The Met Office has issued a yellow weather warning for fog for the East Midlands.
The warning is in force from 8pm tonight (Monday) to 12pm on Tuesday and warns that visibility may fall below 100m in some places.
It adds: "Given the time of year only a slow improvement to conditions is expected on Tuesday morning though cloud arriving from the west may help lift the fog.
"Slower journey times are likely with delays possible to bus and train services. Some delays or cancellations to flights are also possible."