Is my Lennox Y2081 wiring compatible with the Nest?

[Tlcrain]

Here is my current wires being used :

C   Y1   W1   W2   G   R

Can I use a Nest?

[laurentbourg]

This looks like a 2 stage heating, 1 stage cooling. Please confirm. If that is the case, then yes you can use the Nest learning thermostat 3rd generation.