Environmental health officers from Pembrokeshire County Council are investigating an outbreak of sickness and diarrhoea at Goodwick primary school in Fishguard.
A hundred and seventeen pupils out of a hundred and twenty six failed to turn up for class today.
Thirteen staff are also absent.
Parents have been told to keep their children home until they're clear of symptoms for 48 hours.
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It should continue to become drier and brighter from the west. However, a sharp shower is possible.
The heaviest bursts are expected in the south and east, with some western areas either remaining dry or becoming dry by dawn.