How does snow affect mud?

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Dear Tom,
I was wondering if you could tell me why, after snow melts, the mud has a “slimy” context. However, after it rains, it’s more of a packed together, “clumped” mud.
— Jenn Stemmet

Dear Jenn,
The variable consistency and appearance of mud has many explanations, but what you have noticed has to do with the temperature of the soil. Mud that remains after snow melts is probably only a thin unfrozen surface layer, and immediately below it, the soil is still frozen. The frozen soil prevents water in the surface layer of mud from percolating downward, and the mud will have a watery or slimy appearance. However, mud following rain lies above unfrozen soil. The water content of this mud is less because much of its water has filtered downward into unfrozen soil immediately beneath it. The mud will appear more consolidated.