What's the saying about cloudy days on the fifteenth day of the first month?

On the Mid-Autumn Festival on the 15th day of the eighth lunar month, if the sky is covered by clouds (cloudy or rainy) and the Mid-Autumn Festival cannot be seen, then the 15th day of the first month of next year will be cloudy or snowy.

It is not unusual for the ancients to sum up the sentence "It snows and lights on August 15th in Yun Zheyue, and on the 15th day of the first month". There were no high-tech means and scientific instruments in ancient times, and people's experience came from the summary of life. Our ancestors were good at observing the weather, summing up experience, and also had a certain empirical basis for forecasting the weather. They summed up the rhythm of various weather phenomena, that is, when a weather appears, the corresponding weather may appear again in the next few days.

The time of this so-called weather rhythm is not uniform, with long and short. The most recognized weather rhythms in the records are 30 days, 60 days, 90 days, 120 days, 150 days, 180 days and 240 days. The time between Mid-Autumn Festival and Lantern Festival is exactly 150 days according to the lunar calendar, so our ancestors summed up this weather forecast as a proverb to warn the world. Of course, this statement has no scientific basis from the perspective of modern people, and it is an ancient popular folk saying with backward technology. However, according to ancient records, most of the meanings conveyed by this proverb have been verified. It is true that when the Mid-Autumn Festival is overcast, there will be snowy or cloudy weather on the Lantern Festival!