It's Cooler in Washington

Biking the Trinity Trail today from Gateway Park to the Stockyards I came upon a section of the trail that had little inspirational messages chalked onto the pavement. Blurbs like "Love, Live, Learn" or "Encourage the Person Next to You."

This must have been for some race or walk charity type thing. When the trail went by a church I came to the last of the messages, that being that "You Made It!"

Only one of the chalked messages seemed out of whack, though it made perfectly good sense to me, that being the one you see in the photo, "It's cooler in Washington." I don't know what meaning of the word cooler the writer is intending. Either would be right. I suspect in this case cooler is likely a temperature comment.