A YELLOW weather warning for fog has been issued, with visibility expected to fall bellow 100 metres.

Fog is expected to become increasingly widespread throughout Gwent tonight and overnight into Thursday, according to the Met Office.

Slower journey times are possible alongside potential flight delays.

The warning comes into place at 7pm today and will expire at 11am tomorrow.

The chief forecaster's assessment reads: "Fog patches are likely to form during the early part of Wednesday evening, becoming more widespread overnight with the visibility falling below 100 metres in places.

"Fog will thin slowly later on Thursday morning, although some patches may persist into the afternoon in the west of the warning area."