This winter season sounds very harsh, especially with the thick fog covering everything. Foggy days like this make the cold feel even stronger and create a gloomy atmosphere, almost like night during the daytime. The low temperature you mentioned explains why the air feels so damp and chilling. Winter fog is not only affects daily life and visibility but also brings many difficulties for birds and animals. Your kind message about the helping them by placing food outside is very thoughtful and important. May this cold season is pass safely for all everyone. Stay warm and take good care.