Hmmmm. Well, in my opinion aerating and thatching are never necessary, so I would say, "yes."

Where do you live?

What kind of grass are you putting down?

Spring is not the best time of year to seed new grass. Fall is the best time because the summer weed seeds are not germinating at the same time. When you spring seed and water for the new grass, you're germinating every summer weed seed there is. The second reason spring is not the best time is that the new grass roots will not be developed enough to resist the summer heat.

But if you are going to seed anyway, do it now before the snow. Snow won't hurt the seed. Frost seeding is a real thing and it works.

Do not fertilize now. Wait until Memorial Day. If you fertilize without any grass then you're wasting the fertilizer. If you fertilize grass coming out of dormancy the fertilizer will force the grass to overproduce and you'll be mowing 2x or 3x per week to keep up. Established grass is going to grow like crazy anyway - it doesn't need fertilizer until very late spring.

Seed now. The earlier the better. Aeration has little, if any, advantage to seeding. Depending on the thatching processed used, there may be some advantage to be gained for moisture retention, but it's Spring and that shouldn't be a problem. If this is a reno or a really thin and bare (say 50%) existing lawn, you can add a starter fertilizer now if you have the time or after the snow melts if the seed hasn't had time to start germinating. You don't want to walk on new/germinating grass, so best to do both at the same time if possible. As dchall mentioned, if you are overseeding an established lawn, I'd skip the fertilizer until late May.