Daughter and niece are planning to tour Europe this December/January (London incl.).
As we are from India, would appreciate help on kind of clothes and shoes they should pack.

Thanks

It's hard to say. The best approach (we visited London/Paris in Dec/Jan) is to pack layers of clothes (sweaters, Tshirts, vests, lightweight coat, scarf, gloves) so you can adjust. With luggage restrictions, this can be tough, but if you buy clothes that can be rinsed out, you will be able to extend your range of clothing options.

They will probably really feel the cold as they are coming from a warm climate. If they don't have a heavy coat, jumpers etc you can usually buy them cheaply here at charity shops.

It can be very warm inside shops, museums etc so best not to wear thermal underwear etc as you can't strip that off easily once inside. If you wear a warm coat, you can more easily take that off.

You will need waterproof shoes with nonslip soles (in case of ice or snow), a warm coat, scarf, warm hat, as well as trousers, jumper etc underneath. Also an umbrella of course. You can buy all these things in Europe/London if you need to.

Kay

Wool hat, wool scarf, wool gloves are a must. Make sure their hats cover the ears.

I know most people disagree with me here, but my preference (esp for youngish people) is a lightweight down jacket. Not those you see on Arctic expedition, but a light to medium weight. They are light, very warm, and quite water resistant. I find them very versatile. I have a black one that's princess cut, so it's slimming and not bulky at all. I have no trouble wearing it to nice restaurants.

Of course, gloves! How could I forget? And warm gloves with a wool or thermal lining, otherwise your hands will freeze.

Kay

definitely a sweater, coat, scarf, hat and gloves. its bitter cold in london. not much colder than new york, but the cold somehow creeps into your bones in london....

There's really just one word you need to know:

Primark.

At the extreme west of Oxford Street, a hundred yards east of Marble Arch tube station.

You arrive at Heathrow, and get a tube or prebooked car to your hotel. Since we're 4.5 hours behind you, that usually means you arrive at your hotel (off a 6 am flight from Bombay or Delhi) around lunchtime, so a room ought to be ready.

Unless you live somewhere cold, (in which case you wouldn't be asking this question), the likelihood is cold-weather clothes aren't easily bought where you live. London sells little else - and, contrary to the absurd myths that buffoon ex Trade Minster of yours, Kamal Nath, is always churning out, it's all made in South Asia or China. Little in India of course (you just don't make cold-weather clothing) - but loads in far cheaper Bangladesh

So once in the hotel (and so far, your journey's all been climate-controlled) go to Primark. Judge for yourself how cold it really feels. Then gorge on the right amount (for you) of the cheapest cold-weather clothing you'll find anywhere.

If you're going straight home afterwards, you won't need it again unless you fancy a trip to the mountains. So buying anything "flattering" is silly.

Don't overegg it. There are Primarks all over, and for a week or two you don't need too much. Why buy glove inner liners when God invented pockets to put your hands into, for example? And how do you know other people's cold-aversion is yours? FWIW, I simply never wear gloves, and I'm out in the fields 2 hours or more a day. Throughout the winter

Nor do most of the several million South Asians who live here and don't go into North American conniptions about a bit of rain.

Judge for yourself before single handedly keeping China's or Bangladesh's garment industry in business

Winter in UK can be anything from "mild" to "freezing"...and this is the problem.
Below freezing water is dust and ice, but in UK it is often just above that and the main problem is the all pervasive damp - protect yourself against this with quilted and water resistant coats/anoracks - probably best to buy them when you arrive as they will be more appropriate to local conditions and cheaper even.
just bring one "warm" piece of clothing (a fleece?)to survive the first 12 hours until you can buy something.

I agree with Khunwilko it is the damp which most foreigners find difficult. People from much colder places like Canada and Norway all say that the damp makes it feel very cold although the temperatures may be up to 10 or 14 Celsius in the daytime. Young people seem to be able to cope better.

If the weather is truly awful then you can be indoors a lot of the time whether it is the tube and bus, shops and visitor attractions so you can warm up. Despite what Americans on this forum say heating levels are reasonable in the 20s Celsius. Layers are the answer and scarves together with hats and gloves help to keep the dampness and chills out.

Good walking shoes, perhaps with socks are sensible because they will walk quite a lot whatever the weather they encounter. I have put the worst spin on the dampness they might be lucky and have fine dry weather but nobody can predict.

I have known lots of overseas students from South East Asia and they all complain that it is in the 2nd year of their studies that they find the winter weather gets them down.

We need to know exactly where in Europe they will visit, in addition to London. If they are visiting the far south they also may want summer clothes such as light cotton tops & skirts or trousers. If they are visiting the far north or mountain regions they will need extra bulky clothes.

As for London - personally when I lived there I found a winter coat too hot and never wore a hat - a raincoat was better, plus occasionally gloves &/or scarf. London doesn't usually get that cold, it is still hot on public transport and warm in most public buildings. Plus they may not spend much time outside. (I have always needed a winter coat in the rest of the UK, though.)

Both of my points I think add weight to the argument that layers are best.