According to the the latest weather report, tomorrow's temperature will be as low as -30 degrees Celsius, and the wind chill will be -40 degrees Celsius., so I take out a heavy down feather Therefore, I will wear several layers of clothes. According to the the latest weather report, tomorrow's temperature will be as low as -30 degrees Celsius, and the wind chill will be -40 degrees Celsius. Therefore, I will wear several layers of clothes.

I changed the sentences to be broken down in two sentences to make it easier to read. Also, I'm assuming that you want to wear several layers of clothing to be warm tomorrow.

According to the the latest weather report, tomorrow's temperature will be as low as -30 degrees Celsius, and the wind chill will be -40 degrees Celsius., so I take out a heavy down featherwill wear some heavy clothes. According to the the latest weather report, tomorrow's temperature will be as low as -30 degrees Celsius, and the wind chill will be -40 degrees Celsius., so I will wear some heavy clothes.

According to the the latest weather report, tomorrow's temperature will be as low as -30 degrees CelsiusC°, and the wind chill will be -40 degrees Celsius., so I take out a heavy down featherC°, so I will wear thick down clothesing. According to the latest weather report, tomorrow's temperature will be as low as -30 C°, and the wind chill will be -40 C°, so I will wear thick down clothing.

C° - is usually used, easier to read.