The air is a totally neutral temperature (70's) with just enough humidity to saturate the air with the smell of green, but still feel good to breathe. The sky is dimming a bit and the birds are singing their evensongs, and the overcast sky paints everything in pale blues. But the key is the cottonwoods.
We have two cottonwoods across the street, and both are in full fluff right now. When I walked down the drive a moment ago, the air was completely filled with white puffs. Filled, like they were soap bubbles. Some were heaped along the street or tangled in flowers or grass, and some were dancing every so slowly on the street as passing breaths of wind pulled them into slow-motion tornadoes, but the majority of them just hung there, barely passing, and the entire world slowed to a standstill. A bit like the scene in Insurrection when Anij slows time to a stop.
It's nights like this that make you believe in faeries.