I was just thinking about buying gloves today. Would it be overkill to wear gloves under mittens?
Agreed that if you are looking for warmth, go for mittens over gloves. They are also easier to use with hand warmers.
I love my Gordini ski mittens.
I already own a pair of down mittens, but I didn’t think I’d need to use them when it’s “only” 35 or so outside. I just bought a pair of glove liners, which I’ll try out under the down mittens. Hopefully the combination will keep me toasty.
@VeryHappy - So not polar vortex cold ; ). For current weather conditions, I love my “weatherproof” gloves. They are fleece lined on the inside and then have a water/wind proof exterior. I used them today on my walk and it was in the teens and my hands were very comfortable. Unfortunately they’ve been discontinued so probably not helpful 
I think I have skinny fingers, and that’s why my hands get particularly cold – actually, painful.
For the most extreme answer, I know skiers with circulation problems who wear battery heated mittens and gloves. Outdoor Research gear gets rave reviews and they have a lifetime guarantee. The down side is the price.
Yeah, I saw them – they’re like $160!!!
Get a box of Hot Hands from Amazon or Home depot https://hothands.com/ and activate (“shake”) them 10 minutes or so before you plan to walk the dog. Then put them in your mittens. Toasty warm for HOURS.
I have my eyes on these old-timey 4-ply boiled wool mittens by Dachstein:
https://www.sweaterchalet.com/quality-woolens/mittens-gloves/
When hiking, I layer my hands too. Usually I have a wool base layer shirt with a thumb hole. Then Smartwool glove liners under a wool mitten or under a Thinsulate mitten.
And, I carry these with me, just in case. Hand warmers.
I was also going to suggest the hand warmers. Costco sells a big box (40? 80?) for under $20. SO worth it. H and I will share a pair - he will go for a walk and then a couple hours later they are still good for me to walk with!
I also agree with the gloves under a mitten.
When I lived in NJ, I loved my Ugg gloves. The shearling kept me warmer than other types of gloves. And I always had a big box of hand warmers from Costco. Would stick the hand warmers inside my boots too.
Brrr—have never seen box of Costco hand warmers. I can see how those could be handy!
LOL @Midwest67- look at the post above yours 
Not saying this to be bossy but just pointing out IF you have a membership to Costco the box they have is SO much cheaper- they are the same concept - shake and they heat up - the heat usually lasts 8 hours.
I think they usually go on sale at least once a winter - 80 packs!
https://www.costco.com/little-hotties-hand-warmers%2c-80-pairs.product.100415857.html
The problem with buying a ginormous box is that they have a shelf lie and eventually dont seem to work. I bought it once, and the box lasted a few years. Took a bunch, like normal, on a ski trip and they were past their prime, shall we say.
Well it depends how often you use them. 80 packs is nothing for a midwest winter where you go out daily walking a dog or to exercise! OP mentioned out walking her dog which could certainly happen frequently!
Just invest in a good pair of gloves/mittens. Cheaper in the long run and better for the environment.
I agree with @doschicos. Good thick mittens, or of you need to use your fingers, good quality ski gloves. Also make sure the rest of you is really warm. Your fingers will stay comfortable longer if your core is warm.
@abasket- Where VH lives she could use the hand warmers frequently in the winter. But 80 pr is a lot. Do you use them every day?
I had a bunch left over and ended up giving them to a massage therapy student who was doing home massages and looking for an alternative to hot stones!
I think 80 pairs is too many for me. I walk the dog every other day (DH and I alternate days) and where we live (in CT) there are some days when it’s not that cold. As I mentioned, I ordered the glove liners, which I’ll try with my down mittens. I might buy a couple of pairs of the hot hands to use on very very cold days. Thanks, everyone.