1) Yes, very important.Weather people interested in such professions as gardeners, drivers, builders, sailors, pilots. Using this information, they can understand what the weather will be in the next few days.
2) People often listen to daily weather forecast once a day or several times a week. No, people can also get it in the Internet.
3) All day and night, weathermen are collecting information from ships, planes, weather stations, and space stations.
4) When a barometer shows high pressure in summer the weather will be hot and sunny. When a barometer shows high pressure in winter the weather will be cold and frosty.
5) My parents usually watch TV, and brothers and sisters watch online
6) (просят рассказать были ли у вас неприятности из-за неверного прогноза погоды)