Around 40 schoolchildren are awaiting rescue after their bus slid off a road near Crymych in Pembrokeshire.
The pupils, from Ysgol y Preseli, were on their way home after their school closed early due to bad weather.
It happened between Maenclochog and Mynachlogddu. There are no reported injuries.
A spokesperson for Pembrokeshire County Council said: "The pupils are staying onboard while waiting for a relief bus to collect them and continue their journey."
On Monday, 16 children and three adults had a lucky escape when a schoolbus slid off the road and became trapped on an embankment in the village of Llanfach, near Abercarn.
More top news
You've been sending us pictures of your children dressed up for World Book Day.
A brother is facing jail for killing his step-sister when she fell off a motorbike he was 'racing' in his car in December 2013.
The Prestatyn Scala cinema that closed after campaigners fought a lengthy battle to save it is now set to re-open under new management.