If someone gives you a snow job, it means they are saying something which is insincere or untrue. Sorry, but used car salesmen are notorious for doing this! The pattern is “give [someone] a snow job.”
– I knew the used car salesman was giving me a snow job about that old Ford, so I didn’t buy it
– Don’t give me a snow job! Just tell me where you went last night!
I hope you can stay warm on this snowy day and don’t let anyone give you a snow job!