北京小寒后冷空气频繁，明日北风劲吹，双休日再降温

Group 1 - The article discusses the weather conditions during the "Minor Cold" solar term, indicating it is one of the coldest periods in Beijing, with frequent cold air and temperatures dropping significantly [1][3] - The highest temperature recorded on January 4 was 6.5℃, while the lowest was -7.9℃, highlighting the cold weather extremes [6] - The forecast predicts a maximum temperature of around 7℃ during the day and a minimum of -5℃ at night, emphasizing the need for precautions against cold weather [3][7] Group 2 - The article mentions that the weather will be clear with a slight south wind, making it suitable for outdoor activities during the day, but warns of rapid temperature drops at night [3][6] - It notes that the upcoming week will see fluctuating temperatures due to frequent cold air activities, with daytime highs only reaching 4-5℃ and nighttime lows between -7 and -4℃ [10][12] - The article advises the public to pay attention to temperature changes and dress appropriately to prevent cold-related health issues, particularly for vulnerable groups [16][15]