Read the sentences.

the snowstorm lasted for hours. the wind and the snow mingled with the air.

what punctuation and/or conjunction can be used to combine them?
hours, and the wind

hours, the wind
hours; and the wind
hours and the wind

"hours, and the wind" is correct and uses what is called an oxford comma.
"hours, the wind" can be considered to be incorrect as it creates a run-on sentence.
"hours; and the wind" is technically correct however using the semi colon doesn't require the following "and" and can be considered to be superfluous"
"hours and the wind" can also be considered to be correct even though it doesn't use the oxford comma, however, some might consider it incorrect as the oxford comma is considered by many to be obsolete.