During the summer of 2025 (June-August), the Northern Hemisphere polar vortex exhibited a unipolar distribution pattern, with its main body located within the Arctic Circle and the center shifted toward the Eastern Hemisphere. The mid-to-high latitude circulation displayed a 4-wave pattern configuration, while the Eurasian continent experienced a “two troughs and one ridge” circulation pattern. From June to July, the western Pacific subtropical high was stronger than the climatological average and positioned further westward and southward than normal. A total of 14 tropical cyclones formed in western North Pacific and the South China Sea, representing an increase of 3 systems above the long-term average. Five of these tropical cyclones made landfall along China’s coastlines, among which Typhoon Danas followed a historically rare track, making initial landfall on the western coast of Taiwan Island before recurving westward to make a second landfall in Zhejiang. Additionally, 19 tropical cyclones developed in other tropical oceans. China’s offshore waters experienced 6 occurrences of gale-force wind events (Beaufort wind scale 8 or above), all induced by typhoon activities. Eleven significant wave events with wave height exceeding 2.0 m were recorded in offshore waters, and the most extreme wave event of the season occurred from 11 to 14 August, influenced by Typhoon Podul, with the maximum wave height reaching 9.0 m. Five notable sea fog events were observed in China’s northern sea areas, with 4 occurring in June and one in July. The sea surface temperature (SST) across China’s offshore waters was generally on the rise, with a significant warming trend in the northern sea areas. In August, the SST anomalies were 2-3 ℃ higher than the climatological mean in the same period.