The road looks wet because of diffusion. See the attached link.
Harvard "Hot Road Mirage"
http://www.fas.harvard.edu/~scdiroff/lds/LightOptics/HotRoadMirage/HotRoadMirage.html
A distant patch of road can appear wet on a hot summer day due to the heat rising from the heat road surface. It refracts (move, bend, or deflect) the image of the road in a wavy manner creating the illusion of water.
Generally speaking a wet road is a slick road. Because water on the road surface brings up oils deposited by traffic over time the road becomes slick. I can only imagine that if it is a hot day this will only make it easier for the oils to float.
Because its a hot day init
hot ,wet,
Weathering is faster with temperature extremes such as very hot by day and very cold by night. Look at Bryce Canyon with its sharp angular landforms.
yes
Only a few of the rides get you wet, but go on a hot day so you can cool down!
Lions seek a shady location in the heat of the day.
a wet road also see hydroplaning
wet-bulb tempature
A wet road has less friction since the water acts as a lubricant.
Because on got day there is less moisture in air so, the clothes dry faster on a hot day than a cool day.