However, Pinchbeck said adaptations to homes and communities were needed immediately "regardless of what you think we should do in terms of reducing emissions".
In her first televised interview since taking up the post of chief executive at the Climate Change Committee, she said: "We're off track against where we should be - and that's things like flood defences, or are our houses built on flood plains?
"In the summer are our cities ready for extreme heat? These basic things."
Pinchbeck said the UK must plan for more extreme weather events like Saturday's storm, adding: "We have to prepare our infrastructure for it.
"We have to prepare the economy for it. We have to prepare our homes for it."
The government's own climate risk assessment, published in 2022, warned the impacts of a changing environment could cost the UK billions of pounds a year.