Snowfall

If it snows tomorrow, I will need to buy a pair of gloves.

I'll try but it's better to wait for the teachers' correction. Because I'm not always sure of my answers.

You could say:

-If it snows tomorrow, I will need to buy a pair of gloves.

Why not to just say:

-If it snows tomorrow, I'll buy a pair of gloves.

The word "Snow" itself can be used as a noun or a verb, so I used it above as a verb.

sundarnazsnowfalls

Snowfall is a noun, not a verb.

The snowfall in the mountains amounts to several meters each year.
A heavy snowfall can snarl traffic for hours.

Combining rainfall and snowfall, my city averages about a meter of precipitation each year.

I will need to buy a pair of gloves before the first snowfall of winter.