Alec Kerr's list hits this century! Of 'Summer Days' (2000) by Phoenix, Alec says, "A country-tinged song from the English-singing alternative French band that is as upbeat as a warm summer day."
Next up is 'Feels Life Summer Again' (2002) by The Wallflowers. "Jakob Dylan, the driving force behind The Wallflowers, will never be his father Bob Dylan, but he's a talented writer of crisp, clever pop songs. Plus he can sing better, too." You can hear a snippet here.