As a habitual park goer, it's not an overstatement to say the daily evolution of the seasons is quite evident providing an entirely new set of vistas and experiences for each visit to Central Park...no matter how many times you might've already been there.
I'd wager Spring is by far the best season. In March, daffodils and other flowers begin appearing scattered about poking their heads through late snow when necessary. Moderate temperatures begin luring NY'ers out of dreary, cramped apartments; park attendance especially swelling after the first Sunday in April and DST.
The fountains get filled and drinking fountains turned on while new buds on trees/bushes cast a fresh light-green coating across the horizons. By mid-May, flowering trees are beautiful; the highest concentrations around Tavern on the Green, Cherry Hill, the eastern park look behind the art museum, the eastern bridle path along the reservoir, and in Conservatory Gardens - a definite must.
If you can't stand the heat, head for the park! Vegetations are at their lushest providing cool shade during summer months, but it's the massive amounts of people which become the main attraction. The park is abuzz with activities everywhere, though quiet moments are still available whether amidst the crowds or in solitude. Street performers, as well as the Summer Stage concert series and performances at Delacorte Theatre, provide daily entertainment beyond obvious people watching opportunities. Ferocious night time thunderstorms, conjured up by the most wicked humidity, can cause the ground to produce steam which yields a ghastly, eerie ambiance to the natural magical mystery.
Mild fall temperatures generously extend summer-like activities with trees offering little seasonal hints. They're not many Maples and others with vibrant fall foliage, but many shades of yellows/browns paint an entirely different landscape whether leaves are still clinging to trees or carpeting the ground. Judge for yourself, but there always seems to be a sense of desperation in the air the last Saturday of October as people fully indulge before losing the hour of park daylight come Sunday with the time change.
Enjoyable weather has usually stuck around until the week of Thanksgiving and Mother Nature drops the bottom out of temperatures. While not as great in numbers, you'll note the serious park patrons still walking dogs, jogging/biking and seeking refuge in this Edenistic escape...just more bundled up.
Central Park is not to be missed in winter! Bare tree limbs no longer conceal the towring rows of buildings surrounding the space; even more evident after 5:00 p.m. when all the lights come on. Take a walk with someone special; snuggled up for warmth...imaginary mistletoe hanging off any/everywhere! When there's snow/ice, proceed with caution walking across the frozen lakes. I see people doing it every year - yet someone always falls through!
And then, counting the days until Spring...