Answer:option A is correct; cold front.
Explanation:
A cold weather front is defined as the changeover region where a cold air mass is replacing a warmer air mass.
From the question which says that the weather forecast was; ''
Increasing cloudiness and warm today with the possibility of showers by this evening. Turning much colder tonight. Winds southwesterly becoming gusty and shifting to northwesterly by tonight.''
When the cold front is passing, winds become gusty; there is a sudden drop in temperature, and heavy rain, sometimes with hail, thunder, and lightning. Lifted warm air ahead of the front produces cumulus or cumulonimbus clouds and thunderstorms.