Just had a look at accuweather H & seen where the real feel of minus 10 is forecast. Early today, I was hanging out washing, after the sun came out, & would say it felt like -1 / -3, mainly because of the stiff breeze coming straight from the mountains.
With gusts of 70mph + forecast tonight, I guess that a lower temp is possible before sunrise. Think I'll have to find the thermals again!