How to judge the daily temperature difference by isobar

The essence of comparing the daily temperature difference between the two places in the isobar diagram is to investigate the weather conditions in the two places. If it is in a low-pressure center, it is mostly rainy and the temperature difference between day and night is small; If it is a high-pressure center, it is mostly sunny, and the temperature difference between day and night is large. If it is located in a trough with low pressure, it is necessary to judge whether a cold front or a warm front is formed, whether it is before or after the front. Generally, there is rain and snow after the cold front, that is, rainy weather with small temperature difference; It is usually sunny before the cold front, and the temperature difference is large. If it's a warm front, it's rainy before the front, with a small temperature difference, and sunny after the front, with a large temperature difference. The high pressure center and ridge must be sunny. As long as we judge the weather conditions in the two places, we can get the answer.