Weather in New York is hot and humid in the summer, and cold and dry in the winter. Your dorm will be hot and humid when the heat is on, and cold and dry when the heat is off. See also shoulder seasons.
Wikipedia describes the New York climate here.
Weather forecasts for 10027
- New York Times
- Weather Underground
- National Weather Service
- National Weather Service Technical Discussion
The last one is really interesting when there's a big snowstorm or any other major event in the forecast, since the NWS forecasters talk about their uncertainty and the way the models have been behaving. It helps put incorrect forecasts in perspective, and the jargon is entertaining.
For those who really want a comprehensive forecast, Weather Underground or the National Weather Service are good because they include both the digital forecast (exact temperatures) and the more scientific forecast descriptions with temperature ranges, not to mention the discussion described above.
For long-range forecasts, Weather.com predicts up to 10 days out, and Accuweather.com predicts up to 15 days out. They are both almost never correct.