The Met Office has issued a yellow alert for the majority of the county – but not for Portsmouth and the surrounding towns.
It comes into force at 5pm today and remains in place until 11am tomorrow.
Commuters are being warned that there is potential for travel disruptions due to the fog.
On its website the Met Office says: ‘Fog patches will form during the evening and then become more widespread overnight – perhaps leading to some travel disruption.
‘Slower journey times with delays to bus and train services possible. There is a chance of delays or cancellations to flights.
‘Fog patches will reform during Thursday afternoon, particularly in river valleys and near lakes, and may become…