With plummeting temperatures and chilly winds blowing, Shenzhen meteorological authorities upgraded a yellow alert for cold weather to orange at 4 p.m. Thursday, forecasting further drops in temperature in the next few days.

Affected by a strong cold front, temperatures began to drop in Shenzhen on Dec. 16 and the overnight temperatures plummeted by 17.4 degrees Celsius.

Influenced by a continuous replenishment of a cold snap, the lowest temperature in the city will drop to below 5 degrees Celsius on Friday. The orange warning will remain in place for two to three days, forecasters said.

An orange alert indicates that either the lowest temperature will drop below 5 degrees Celsius or that the daily average temperature will persist below 10 degrees Celsius.

At around 9 a.m. Thursday, the lowest temperature on land across Shenzhen was 5.4 degrees Celsius, recorded at Tiezai Mountain in Xixiang Subdistrict, Bao’an District. In high-altitude areas, the lowest temperature was minus 0.9 degrees Celsius, recorded on Wutong Mountain in Luohu District. Among all temperature recording stations in the city, 217 stations recorded temperatures below 10 degrees Celsius, and eight stations below 5 degrees Celsius.

Citizens are advised to take precautions to stay warm, prevent carbon monoxide poisoning when using heaters, and control and prevent diseases. Shelters for avoiding the cold across the city are open for those who need it.

The good news is that the mercury will pick up next week. In the latter half of next week, it will be sunny and dry, with the highest temperatures to rise to 20 degrees Celsius and above.

In Guangdong, nine red and 53 orange warnings for cold weather had been issued as of around 4 p.m. Wednesday.

Nationally, the country’s meteorological administration continued to issue a yellow cold wave warning at 6 a.m. Thursday. The lowest daily temperatures in parts of the country from Tuesday to Friday, including Guangdong, were more than 5 degrees Celsius lower than the historic average for the period, it said.

China has a four-tier, color-coded weather warning system, with red representing the most severe weather, followed by orange, yellow, and blue.