Understanding the GFS 'Height of 0 degree isotherm' chart

Hi guys. Tonight I decided to write about a chart that is crucial to forecast where precipitation will fall as snow. And since we're closing in rather quickly to winter, it will help substantially with your forecasts.

The above is the 0 degree isotherm chart produced by today's 12z GFS run.
Basically, the chart shows the height (in meters) in which the temperature is at 0C. The chart is fairly straight forward, and is especially useful for predicting the snow level on mountains.
The key on the side of the chart is colour coded. It measures the height in meters. The chart goes up to 6000m, and down to -500m. As a general rule you will find that the isotherm will need to be at 200-300m for snow to fall at sea level.

So as an example: This current chart tells us that snow will not be falling in the UK, even over the highest peaks of Mt. Everest. It does however tell us that the 0 degree isotherm is very low over Siberia, it's at 0m and therefore any precipitation is likely to be snow rather than rain.

That's all there is to it. One of the more simple charts produced by the GFS.

Thanks,
~Jordan.