Where to go for 3 nights in Switzerland next week

There are 2 different possibilities that I would suggest:
Base in Lausanne which has easy train access. Lausanne has beautiful views of Lake Geneva and a lovely Old Town area.. Stay in the Port D'Ouchy area of Lausanne. You could take the train to Montreux to see the Chillon Castle, or train to the charming town of Vevey and go to Laederach Chocolates, or see the Unesco Site Lavaux Vineyards. Gruyeres is not too far either.
Or
Base in the Lauterbrunnen area and stay in Wengen for the views, or base in Interlaken which has easy train access to Wengen, Grindelwald and Lauterbunnen.
I would suggest staying in either Lucerne or Zurich the night before your flight, so you really only have 2 nights Dec. 16 and 17 to try a new area. .

Would your daughters like to have the option of some additional skiing days? If so, of the places you list, Wengen is the best choice.
Otherwise, somewhere along the lake between Montreux and Lausanne (I like Vevey), bearing in mind that it can be quite foggy at that time of the year.

I can see why the Swiss might not favor Lauterbrunnen for their own holidays—-the area is very touristy (popular with foreign tourists). In Mürren I feel like we are surrounded by more Brits, Americans, and Australians than Swiss people.

And you have beautiful mountains and such good skiing close by your home (Whistler), why look for more of that in your short time in Switzerland? *

I think your inclination toward visiting Suisse Romande (the French-speaking region) around Lac Leman is a good idea; perhaps you can find some fun Christmas activities (markets, concerts, lighting displays) and there is always the Chillon castle to explore. Just be mindful of Balso’s comment regarding fog in the lake area. Maybe your daughter will have some good suggestions for a town to stay in.

• And now a quick story: when I started taking my teenage sons to Whistler for skiing 30 years ago, we stayed at a small bed and breakfast named Swiss Cottage or something like that. The owners Willie and Louise were Swiss mountain guides and ski instructors. I asked Willie why they left Switzerland and moved to Whistler and he responded, “Because the skiing is much better here”.
  

In Lucerne you can easily go to the top of Mt. Rigi, and maybe see the sun? In Dec, 2019, we were there, the city was clouded in, but as the cogwheel train was climbing Rigi, absolutely socked in the fog, suddenly we rose above the clouds, and had the most spectacular blues skies framing fresh-snowed peaks. It was magical. I think there are cameras to determine how clear the summits are.

Bern has nice xmas markets, and staying your last night in Bern works for flying the next day, as the train just takes a little more than an hour to get to Zurich. The Zurich main train station has the largest indoor xmas markets in Europe, and I THINK the market is happening this year.
Best wishes for a wonderful trip and sharing time with your daughters!

All excellent suggestions! Thanks, everyone. I'll discuss with my daughters and go from there.

Back from my trip with my 21 yr old daughter and I want to share what we ended up doing . . .

Fri: Landed in the snow in Zurich, by the time we got off the train in the city, it was raining and a slushy walk to our hotel. A cozy night in Zurich Old Town. All good

Sat: train to Zermatt, passing through a very foggy Thun & Spiez area, but climbing up to Zermatt in the sunshine. Met with my older daughter to deal with family issues, but also raclette dinner

Sun: woke up to crystal clear Zermatt. Daughters skied, and I took about 4 gillion photos of the Matterhorn. Funny, this was NOT on my bucket list and I never thought I'd go to Zermatt, but I did and lucked into the most fabulous winter weather. Worth a visit if you know it's going to be clear.

Mon: travelled to Luzern where older daughter lives. Berner Oberland was fogged in, again. Arrived at Hotel Des Alpes in Luzern to panoramic Alp views. Took many photos before nightfall. Good thing! We stayed there 6 nights and it was fogged in the rest of the time. Temps were -2C at night and +3C in the day the whole time. Went to the Luzern Christmas market that night

Tue: the three of us took a boat to Weggis, and then went up Rigi to Mineralbad & Spa Rigi Kaltbad. Gorgeous views of the Alps above clouds. The spa was lovely and recommended. Daughter who lives in Switzerland said she definitely has to come back on a weekday rather than the weekends when she usually goes and it's crowded.

Wed: Swiss daughter back at work; we hung out in the Old Town, and walked around the medieval wall on the north side of the city (we've both been to Luzern twice before, but had never seen this up close). Relaxed at a gluhwein spot with a fire pit.

Thurs: Day trip to Montreux. It was pretty foggy there too. Explored Chateau de Chillon, which is a must-see for history buffs. I've done quite a few European castles, but here we were alone in the dungeons, on a dark winter day, with the lake lapping against the wall and it was genuinely CREEPY! I've never felt that before. Also, it was super interesting. Definitely got our steps in that day

Fri: dealing with COVID and family crap. But we had lovely fondue dinner outside our hotel along the river, which was amazing

Sat: weekend! The 3 of us wanted to be above the fog. Went to Stans, with the thought of going up the Stanserhorn (which 2 of us have done before). LOL, it's wrapped up until April. But there was some Swiss festival going on (we later found out it was pre-pre-pre-Fasnacht), We showed our Swiss covid passes to get in, and went to buy gluhwein, but they only had some hard alcohol punch, which was free, and many people were having fun dressed up in costumes. Big tubas and drum kits on wheels felt a little like I was in a Dr Seuss book. Maybe it was the punch. Anyway, after one drink, we hopped on the train to Engelberg, with the hopes of going up Titlis, but it was too late. I've been to Engelberg before and it's lovely and it was clear with sun on the mountaintops.

And there you go. Family issues dealt with, a little fun had. I have to say, I very much enjoyed riding the Swiss trains. Of all the stupid money I had to spend on this trip, the Swiss pass was the best deal

Thanks for your interesting report. Glad it turned out so well! Sounds like you were flexible and didn’t let some less than ideal weather spoil your trip.

Glad you had an enjoyable trip and thanks for the summary!