Statistical Characteristics of Tropical Cyclone Gale and Its Accompanying Weather in Southeast China

The China Meteorological Administration (CMA) tropical cyclone best track data and hour-by-hour precipitation data from 2010 to 2016 were used in a statistical analysis of surface gales and their accompanying weather in southeastern China under the influence of tropical cyclones (TCs), and the results show that: (1) In this region, TC gale is primarily dispersed along the coastline, with decreasing frequency from coast to inland; TC gale is dominated by the northeast wind direction, and the gale occurs primarily before the typhoon landfall. Strong wind speeds of magnitude 12 and higher are scattered within 300 km of the TC center; (2) TCs of tropical storm (TS) and typhoon (TY) intensity caused the most gales, while strong wind speeds of magnitude 16 and above are mainly found in the severe typhoon (STY) and super typhoon (Super TY) intensity classes. Gale induced by slow TC appears primarily on the right front side, while gale caused by quick TC appears primarily on the right rear side. The mean onshore wind speed of TC gales is slightly greater than the offshore wind speed, despite the fact that the station frequency of onshore wind is greater than that of offshore wind when the wind speed is between level 12 and level 16, and when the wind speed is above level 16, offshore wind is much greater than that of onshore wind; (3) The percentage of TC gales that are precipitation-accompanied accounts for roughly 89.8% of the total number of TC gales; these gales are primarily caused by northeasterly winds, peaking in August. About 10.2% of the TC’s gales are dry, with the majority occurring at the TC’s periphery with weak northerly and southeasterly winds, primarily in May and December. TC gales with wind speeds above level 12 are almost always accompanied by precipitation, while there are few samples of TC gales with wind speeds above 12 without precipitation; (4) TC gales accompanied by strong convective weather account for approximately 23.8% of the total TC gale, with northeasterly winds dominating, the average wind speed is larger than the non-strong convective TC gale; strong convective weather with short-term heavy precipitation and thunderstorms, with the majority of which is short-term heavy precipitation (approximately 79.5% of this type of TC gale), mainly distributed in the northeast quadrant near the TC center, while thunderstorm TC gale mainly appears in the periphery of TC (approximately 28.0% of this type of TC gale), of which there are relatively few in the southeast quadrant. (5) TC gale with both short-term heavy precipitation and thunderstorms accounts for only 1.8% of the total TC gale and 7.5% of strong convective TC gale, indicating that thunderstorms are not common in TC gale with short-term heavy precipitation.