I generally find music in general to be very seasonal, so your mileage may vary, but here's a a few for each.
Spring: Shad - TSOL (hip-hop) Asobi Seksu - Citrus (poppy shoegaze) Belle & Sebastian - The Life Pursuit (indie pop) Caitlin Rose - Own Side Now (folk/country) Florrie - Experiments (pop) (hi icon) Sam Cooke - Live At The Harlem Square Theater (r&b)
Summer: Arcade Fire - The Suburbs (obvious) Cloud Nothings - Attack On Memory (rock) Joel Plaskett Emergency - Ashtray Rock (folk rock) (hi again icon) Reflections Eternal (hip hop) Anamanaguchi - Dawn Metropolis
Fall: Robyn Hitchcock - Jewels For Sophia Happy End - Kazemachi Roman Yellow Magic Orchestra - BGM (electronic) Beirut - The Rip Tide (indie)
Winter: Leonard Cohen - New Skin For The Old Ceremony (folk) Portishead - Third (eerie pop?) Shabazz Palaces (hip hop) Aoki Takamasa + Tujiko Noriko - 28 (down tempo electropop?)
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"It's a magical world, Hobbes ol' buddy...let's go exploring!" - Calvin http://img.imgcake.com/calvinfinalpngpy.png
Going through my albums, I'm simply reminded of the season in which I listened to that album most, rather than what season the sound of the album actually represents.
For some stuff that hasn't been listed that I feel captures the essence pretty well...
Fall: Death Cab for Cutie - We Have The Facts And We're Voting Yes Frightened Rabbit - The Midnight Organ Fight Modest Mouse - ...pretty much their entire discography
Winter: The Weakerthans - Reunion Tour
Spring: The Applies In Stereo - New Magnetic Wonder The New Pornographers - Pretty much their entire discography too Tokyo Police Club - Elephant Shell Los Campesinos! - Hold On Now, Youngster...
Summer: Surfer Blood - Astrocoast Ra Ra Riot - The Orchard The Pixies - Doolittle Los Campesinos! - We Are Beautiful, We Are Doomed
Probably worth noting that I'm pretty heavily influenced by when I first listen to an album. I made the mistake of listening to Best Coast and Wavves nearly exclusively for a December and now, as much as I know they sound at least as summer-y as Surfer Blood, they just can't escape the mental association.
On a separate note, I feel that there are a lot of albums that straddle the transition between Summer and Fall; the end of the dog days (at least in the NW United States) is a very distinct period from all other seasons and is I would identify as uniquely notable among seasonal transitions.