It is just one degree. One point along the temperature gradient. One point in time as the temperature rises or falls. Above, and all water falls as rain, soaks into the ground, runs along the surface until it finds a crack or crevice or opening of some sort, and then follows the pull of gravity down into the earth. Some flows on to creeks that fill streams that fill rivers, some that soaks in seeps back out of the ground on the banks to feed the streams and creeks. It is clear and flowing, moving.
Below that point, all water falls as snow or ice pellets or sleet or some other form of solid water, and it drops, lands, and stays there. Solid, accumulating, piling up. Deeper and deeper. Unless the winds grabs and moves it to another place, still above the surface of the earth, so stop and stay somewhere else.
Raining raining raining bam snowing snowing snowing. The earth goes from dark, saturated, absorbing all water and and much of the light to BAM white, bright, resisting the snow that piles up above ground and reflects back bright light from the sky. One day, all is brown and tan and grey and black and the next, it is bright glistening shining white. Everything is like that, but we seldom see the change points quite so obviously. A word changes the way you think about an issue, a person. A moment, a single event, a single act, changes forever the course of a day, a life, a civilization. To see those moments and accept and adapt and adjust is a gift, a talent, a skill, and on that can hinge ones happiness or ones very survival.