That leaves a space between the pot and the snow which can heat up sufficiently to melt a thin aluminium pan or warp a steel one.
It also leads to a phenomenon often described as “burnt snow” which is an odd scorched flavour to the water.
To solve this problem I tended to keep one water bottle purely for “sacrificial” water.
By heating this water and then dropping packed snowballs into it there was always liquid at the bottom of the pan to circulate the heat and melt the snow.
This led to the common description of this constant practice being “making snowball soup”.
In the evening we returned to the lake to set up a few night lines under the ice and to see if we might see the Aurora.