If it's cold outside then the thermostat on your air conditioner won't allow the air conditioner to come on and run.
So when the temperature gets to the setting on the thermostat then the air condition will run.
I never run my air conditioner though until it's at least 85 F outside or if it's very humid then I might run the air conditioner to remove the humidity.
I would say that if it's 65 or 70 F outside that would be too cool of an outdoor temperature to run the air conditioner and you'd likely be freezing.
If possible just open the windows for some fresh air on those nice spring days and save the air conditioner for when it gets into the 80 F and above range.