summery

from WordNet (r) 3.0 (2006)

summery
    adj 1: belonging to or characteristic of or occurring in summer;
           "summery weather"; "summery dresses" [ant: {autumnal},
           {vernal}, {wintery}, {wintry}]

from The Collaborative International Dictionary of English v.0.48

Summery \Sum"mer*y\, a.
   Of or pertaining to summer; like summer; as, a summery day.
   [1913 Webster]

from Moby Thesaurus II by Grady Ward, 1.0

86 Moby Thesaurus words for "summery":
      aestival, arctic, autumn, autumnal, beryl-green, berylline,
      blood-hot, blood-warm, blue-green, bluish-green, boreal, brumal,
      calid, canicular, chartreuse, chloranemic, chlorine, chlorotic,
      citrine, citrinous, emerald, equatorial, equinoctial, foliaged,
      genial, glaucescent, glaucous, glaucous-green, grassy, green,
      green as grass, green-blue, greenish, greenish-blue,
      greenish-yellow, greensick, hibernal, hiemal, holly, ivy,
      ivy-green, leafy, leaved, luke, lukewarm, midsummer, midwinter,
      mild, olivaceous, olive, olive-green, out of season, porraceous,
      room-temperature, seasonal, smaragdine, solstitial, spring,
      springlike, subtropical, summer, summerlike, summerly, sunny,
      sunshiny, temperate, tepid, thermal, thermic, toasty, tropical,
      unfrozen, verdant, verdurous, vernal, vernant, vert, virescent,
      warm, warm as toast, warmish, winter, winterlike, wintery, wintry,
      yellowish-green