I am a complete newb to optics and long range shooting. I recently gained access to some property where I can go out to about 500 yards and decided to try my hand.
Starting out the inexpensive rout, I put a Vortex Crossfire 3x9x40 on a Remington 700 in .308
Have the whole week of Christmas off and would like to zero it in. I figure I will start at 100yds and work my way out.
The question is, the temp here in SW Ohio will probably be in the low 30's during the day. Could the lower temp adversely affect the scope and would temperature affect zero when the weather warms up?
Thanks in advance for any advise.

Temperature affects air density, which will influence the point of impact. Colder temperatures mean greater air density, thus more bullet drag, and a lower point of impact. Also, the powder burn rate will likely be lower, again affecting POI. So, your zero will shift as temperature (more directly air density) changes. The scope should be fine operating in those conditions.

All good to know information. thanks

Let your rifle and ammo adjust to the outside temp before shooting and you'll be fine.