After struggling for months, I finally have a resolution to the intermittent issues with the modeled snow depth maps.  In my testing I have been getting consistent results now instead of it sometimes working, sometimes not.  I also added some styling to make the tiles blur together a bit - I think it looks better than the very blocky look that it had before.

I would be interested to hear any feedback on the changes.  As always, if you find issues, please let me know.  Many of the map services change with great frequency which sometimes cause problems which I don't necessarily catch if it is a function I don't use often.