What classic, timeless but smart jacket/cardigan to wear with this dress?

[Oneearringlost]

What would go well with this dress, I need a skirt or jacket. Im 5'7 size 10.
It is for a smart but outdoor party in mid August. I have some classic flat shoes but am at a loss as to what to wear on top of the dress if it's chilly.
Thank you

Make sure you get your faux leather jacket out in plenty of time to check it hasn't peeled. I think one of those shawl type throws over it would be lovely but one that is sewn up at the front (god knows what the word is - a cape??? What is it 🤣🤣)

Princess Anne MOG style? …

🤔

(It’s true the jacket will need checking.)