I had heard this complaint from the other grad students when I was visiting here, but it's hard to understand how important the sun is for your well being until you've lived without it for months at a time.
[1]: For reference, Cleveland, Columbus, and Cincinnati consistently rank in the top 10 cloudiest cities in the US. (http://www.currentresults.com/Weather-Extremes/US/cloudiest-...)
For some of us, sun and light make a huge difference. And yes, the sun does come out in Seattle, and when it does it's especially beautiful, but in a way that's like saying that you're hitting yourself on the head because it feels so good when you stop. (But I still miss Seattle.)
And no, SAD lights or Vitamin D don't cut it when you're used to seeing the sun on a semi-regular basis.
http://www.nytimes.com/2015/05/03/style/los-angeles-and-its-...
At least when it snows in NYC, the snow often sticks around long enough to be enjoyed.