I’ve messed up with the holiday I’ve booked

You didn’t have a choice? Doesn’t sound like you were forced into it. Everyone knows feb is winter!

When I went to Iceland over winter, I wore tights under jeans and it was fine!

It’ll be fine.

they’re cities and everywhere inside is heated.

i wouldn’t wear jeans though they’re shit in the cold.

layers layers layers.

OP, when I’ve needed specific clothes for holiday but won’t need them in the UK I’ve used Vinted. I got a whole wardrobe for a safari trip on there! 2 years ago I needed snow trousers for my son for a ski trip and got a pair for £14.

As a Canadian who grew up in freezing winters, a good pair of gloves and a good hat will help a lot.

Stick to plan, take warm clothes and have a good holiday. The frightening temps are probably night time, when you'll be asleep anyway. Daytime temps will be bearable. In any case Oslo has good museums that shouldn't be missed. It's probably a dry cold, too, not the damp UK cold. Yrs ago I remember someone from East Canada visiting my home town and finding it too cold, and it wasn't even a particularly cold winter, but she wasn't used to THAT kind of cold. I certainly wouldn't turn down the chance for a holiday in Oslo/Copenhagen in Feb.

It won’t be -30, Copenhagen is amazing. Oslo also great but more expensive from my memory. Both beautiful.

We went to Norway in February and cruised from Kirkenes down to Bergen and once we left Kirkenes we didn’t see any snow at all. Really disappointing because that’s what we went for! Please just bear in mind that ALL buildings, including your hotel, will be super heated. We actually found it unbearably hot, so yes, lots of layers. We found the super thin fleece type quarter zips the most helpful because you can layer without adding too much bulk.

Normal winter clothes with layers will be fine..do you not go out in cold weather at home ? It will be lovely.

I've been to the Nordics several times in the winter and it's fine. Cold but take plenty of layers and be prepared to wrap up well and you'll be fine.

I had a couple of pairs of these trousers. They're fleece lined and waterproof so they keep the cold, wet and wind out. They're not too expensive at £30.

https://www.regatta.com/womens-fenton-softshell-walking-trousers-navy/

You can wear a base layer legging underneath if it's really cold.

Make sure you don't have any gaps. Eg: knee length thermal socks to stop cold going up your legs, tuck your base layer into your waistband to prevent gaps round your middle, a long cuff glove that goes up your sleeve and a scarf/buff to stop cold going down your neck.

Brands like Thinsulate or Heat Holders for hats and gloves are good as they keep the heat in.

I took these patches as well:

https://www.amazon.co.uk/Master-Plast-Adhesive-Lasts-Hours/dp/B0074JJS3K

If you stick one on the small of your back, it's like walking around with a hot water bottle all day! They do help to keep you warm.

I've been to Copenhagen in February. We couldn't go on our planned boat trip round the harbour because it was frozen but otherwise we had a great time. I wore my walking boots but otherwise just normal winter coat, hat and gloves and was fine.

Lapland and Iceland are NOT the same as Copenhagen/Oslo!
There was no snow in Oslo when we went in the February - pretty sure there will not be in Copenhagen but we may just have been unlucky in Oslo.

I definately wouldnt do Jeans, as little cotton as possible.

Thermals and wool, make sure you have a hat that covers your ears, ski socks and good boots. If it did reach -30 is there anywhere you could hire a ski suit locally

We went to Finland last year and it reached -35, our hair and lashes froze but it didnt feel cold really with all the right clothing

Saying winters can get down to minus 30 in Oslo is like saying summers can get up to 40C in London - yes technically that has happened but it’s not the norm you need to prepare for.

I love both cities and you will have a great time. I’ve always wanted to do the big sledge run in Oslo in winter but we’ve only been there in March/April when the snow has gone. Are you taking the overnight ferry between Oslo and Copenhagen?

There are lots of great museums etc in both cities so plenty to do indoors if it is cold and grey. And cofffee and cardamom buns is always a good way to spend time!

Thermals under jogging bottoms are a good idea OP. If it snows and jeans get wet it will be pretty horrible. We picked up some cheap ski trousers and jackets second hand from ebay but we were sledging and stuff so a bit different. Merino wool is really warm and lovely but hugely expensive, I wouldn't bother for a short one off holiday in the south.

You will be fine, we've been to Tromso, Rovaniemi and Kiruna at that time of year (much further north) and although it got cold it didn't get that low even over night. I wouldn't worry at all, it might be minus 5 over night but I doubt it will be much lower than that.

For anything you don't think you'd wear again try sourcing on vinted and resell it when you get back. I would rather have proper clothes than try to make do with things you'll wear again but aren't properly suited to the weather

Pack a hot bottle! I went to Helsinki at this time once and it was -5. Never taken a hot water bottle in holiday before but it was the best thing I did. Nothing stops you carrying around in the day time either I guess.

Be prepared that food/drinks is extremely expensive so unless you can afford it, don't plan on stopping for coffee every couple of hours to warm up. I would have bankrupted myself!

It won't be that cold and it won't be dark either - the equinox is in March so it will only be a little bit darker than England at that time of year.
I took my mum to Copenhagen in December once and went to Oslo in Feb once and both were absolutely fine. Take a coat and good boots/hat/scarf.

As the old saying goes, there’s no such thing as bad weather just poor outfit choices.

You’re a whole holiday deep now. Invest in some decent cold weather gear & enjoy yourself.

I’ve been to Oslo in Feb. It’s really cold but you can still get out and about and the added bonus of the ski slope a short bus ride away. Lots of lovely cafes in the city to hang out in and warm meals at night it’s lovely. Just wrap up warm.

I’m quite used to those temperatures. You just need thermal hat, gloves, socks and under garments. It’s absolutely fine.

OP I go regulary to Norway in Feb as it's my wedding anniversary and we have a business there, we are up further though in the Artic circle. its fine, cold and beautiful but fine.
Look at merino under layers and socks warm but not sweaty, thick soled boots with tread ( acts as a layer between the cold floor) hat, gloves and scarf again merino.
I wear fitted thermal ski trousers over my base and a down filled jacket, layers are your friend as you can take them off as and when needed. I rarely get really cold whilst out and if indoors the Norwegian home/hotels/ cafes etc are toasty.

Oof jeans in cold weather even with thermals makes me feel cold and if there's any moisture not ideal. I wore thermal leggings and hiking boots with thick thermal socks when I went to Oslo in December, and a down puffer, was nice and warm.

There's plenty to do and because theyre cities you don't have to be outside long. I doubt theyd get that cold too tbh, its a rarity.

There are buses and subways so you hop between warm place to warm place. If you're wrapped up warm no reason not to enjoy a warm cinnamon bolle and coffee then hop on the bus to a museum etc. Or a quick ride on the metro to the nordmarka and see a snowy forest and the view for as long as you want to be out in the cold (Oslo).

My husband and I went to Copenhagen in Jan as students. We didn’t have any high tech warm wear. Yes it was cold outside but there was lots to do inside. Tivoli was shut ok but lots of other stuff to wander round. Don’t overthink it and def don’t cancel!