How can I describe a low temperature that doesn't actually feel cold?

Last night, I walked home from my bus stop (in Belgium). Since it was around 11 PM, it was quite cold, probably only about 4-5 °C. However, it didn't actually feel cold at all, and I didn't feel like I had to rush to get home for the cold. In fact, I didn't have headwear on, but I didn't get cold ears. It was about the same temperature as this morning, but the difference is that this morning felt a lot colder, probably due to the wind and drizzle.

I tried to describe it in English on Twitter, but I couldn't actually find a proper word to decribe it. I considered "a warm cold" or "a cozy cold", but I thought these were too poetic, more like something you'd use in a fairy tale than in a tweet to a handful of followers.

How can you describe that temperature without it becoming confusing or poetic?

In American English, we describe cold weather in a positive sense as crisp. As if the cold air hitting your face has a pleasant "breaking" to it.

A Google search for "define crisp" yields this definition, among others:

(of the weather) cool, fresh, and invigorating.

That sounds 'a bit brisk' to me.

brisk

(Of wind or the weather) cold but pleasantly invigorating:

• A cold, brisk wind fills the square on a grey Saturday afternoon.
• Though the wind was brisk and chilly, the sun was bright and warm.
• The September night was chilly, with a brisk wind picking up, but neither seemed to notice.

Here in the UK it's often (though not always) used as a form of humorous understatement, for example on the coldest day of the year you might say "oooh, it's a bit brisk out, isn't it?" c.f. "Nice weather for ducks!"

If it's less cold than you expected then it's mild. As in, "we had a mild winter".

mild

(Of weather) moderately warm, especially less cold than expected:

Tropical continental air is very dry and tends to bring very warm weather during the summer and unseasonably mild weather during the winter.

Plants suffer most when warm / mild weather is suddenly replaced with cold.

October has come round again and the weather is still mild, with the cold snap we had last weekend coming as a shock.

It sounds reet parky!

Example usage: https://www.flickr.com/photos/heandfi/4141559844/

mplungjan's Fresh is a very good suggestion, but have you considered calling it cool rather than
"{adjective} cold"?

Describes the low temperature and implies no discomfort (or you would have used something more harsh than cool)