"It's always a privilege and honour for soldiers to march through the towns and cities of Wales - the places where family, loved ones and friends can welcome them.
"Saturday will be no different and the parade in Caernarfon will be another special day for The Royal Welsh."
The parade will march from the barracks in the town to Castle Square - where the troops will be inspected at 11am.
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The heaviest bursts are expected in the south and east, with some western areas either remaining dry or becoming dry by dawn.
Many places will start dry, but rain in the southeast will spread to most for a time overnight.
The family of Isaac Nash who went missing after being swept out to sea last summer have presented a cheque for £10,000 to the RNLI.