You can actually melt it using "testingCheatsEnabled True" cheat, but then you would need to bring it back, if you want. And it's also not hat fun.
I think there is a way to make markers of any spawner appear in map mode (some mod maybe?). That would make it a lot easier. Also, if it's an opportunity, it think there will actually be markers available.
Try shift and click on the ground. Click on Seasons and Set Snow Level to none. When you've found what you want use the same method to put the snow back to which ever level you had. I believe you need NRaas Tempest to do this.