北京正月初一至初四，最高温重回10℃以上

Group 1 - The article wishes everyone a prosperous New Year and emphasizes the importance of staying warm during the cold weather [1][2] - The weather forecast for Beijing indicates a rise in temperature during the day, with a high of around 8℃, but a significant drop at night to about -6℃ [1][8] - The weather conditions are suitable for outdoor activities during the day, but precautions should be taken to avoid catching a cold due to the large temperature difference between indoor and outdoor environments [1][11] Group 2 - The weather forecast for the upcoming days shows predominantly sunny conditions, with temperatures expected to rise above 10℃ from February 17 to 20, making it suitable for holiday outings [11][14] - A cold front is expected to bring stronger winds and a drop in temperature starting from February 21, with wind gusts reaching up to 7 levels [11][15] - Public health advisories highlight the need for hydration and caution regarding fire and electrical safety due to dry weather conditions [14]