"Winter is my favourite season in Vermont. It's beautiful and unlike anything I experienced growing up in Auckland. It's not a damp cold like we have in New Zealand.
"The coldest I've ever been was in Auckland during winter in the days before we had proper heating. I've never been so cold, chilblains-cold."
Playing Joan, described as "chain-smoking" and "booze-swilling", and apoplectic when things don't go her way at a family wake, should help fuel Harrow's passions, since she's isn't a character approached lightly.
She's a firebrand who unleashes fury "with the help of a $300 bottle of Johnny Walker" adding to her temperament.
"It's a great role for a woman of my age," she says. "Joan is fabulous. As soon as I read it I wanted to play the role. She's so forthright and so brutally honest.
"And I love the fact that she knows one of my favourite speeches from Shakespeare's Twelfth Night.
"Having turned 71 last year, it's a delight to find a part like Joan: an aging actress described as having chronic arthritis and a gammy knee and who also swears a lot.
"That's me."
Harrow cannot be described as a diva. She's been acting since the late 1960s, working throughout the world with some of the best actors and directors in the business. Her son Tim is the result of a union to one of them, Sam Neill, with whom she starred in Omen III: The Final Conflict. But except when a role demands it, conflict isn't her forte.
"The only time I've been called a diva was when I was making my first film in Rome in 1973 with Glenda Jackson," she recalls. "They called her 'the Ball Breaker' and me la Diva'.
"You know, I don't think I've ever met a diva and I really don't know what people mean by that term. Often it's used in a derogatory manner but I think of a diva as a fabulous opera singer who behaves in an imperial manner, like Maria Callas. I've never done that. Others might have a different opinion."
Harrow is certain she will love playing Joan when the show opens in Auckland. "I hope they have empathy for her. If you don't like foul language then some might find her offensive, but I hope they'll be able to see past that and into the woman.
I find her extremely funny and heartbreaking."
Victor Rodger's At the Wake plays at Auckland's Herald Theatre November 25 to December 6.