February is the most overcast month of the year in New England. But on clear, sunny mornings like today, I can really see that the days are starting to get a little bit longer. The sun is rising earlier, and it will set a little bit later.
Daylength changes oscillate like a sin wave, so that there is very little change each day close to the solstices (in December and June), but several minutes of change each day close to the equinoxes (in March and September).
In 2010, the vernal equinox falls on March 20. I'm already counting the days until the first day of spring--and so is my little maple.