The recorded low was just under 5 degrees Fahrenheit, China Daily reported.
In Laizhou Bay, where the Yellow River meets the sea, more than 1,000 ships were frozen into coastal sea ice, the newspaper said.
Since late November, China has been enduring one of its chilliest winters in almost 30 years, the CMA said. The average temperature has been 25 degrees, 7 degrees below freezing.
The CMA said temperatures are expected to rise in the north over the next few days. But the forecast in southern China is for rain, freezing rain and snow in various combinations.
Bad weather has already made many highway difficult.
Yao Xuefeng, a truck driver, was stuck in a massive traffic jam in Jiangxi province in the southeast after a crash.
"I didn't expect such a situation, so I've brought no warm coats or food. All I can do now is wait," Yao told China Daily.