The main number for the Yosemite National Park Service is 209 372 0200 but it is all automated and you will not get a live person.
The main # for the Aramark switchboard is 209 372 1001, they can not connect you to the National Park Service, Just Aramark services.
For road conditions call 209 372 0200, press 1, press 1
Any numbers that are 3 digit add 372-0 to the front of them. These are all 209 area code.