The geographical environment of Jiaocheng District
The main river with hydrological conditions is Huotong River, with a main stream length of 126 kilometers (68 kilometers within the territory), a basin of 2244 square kilometers (517.5 square kilometers within the territory), and tributaries such as Chixi; Qidu River is as long as 58 kilometers, with a basin of 334 square kilometers. The main lake, East Lake, covers an area of 3 square kilometers; the artificial lake Jinhan Reservoir covers an area of 72 hectares. Climatic conditions: The annual average temperature is 19.0℃; the average temperature in January is 9.6℃, and the average temperature in July is 28.7℃; the extreme maximum temperature is 38.5℃, the extreme minimum temperature is -2.4℃; the accumulated temperature ≥10℃ is 6111℃. The annual precipitation is 2013.8 mm, and the frost-free period is 317 days. Spring: Beginning in mid-February, except for high-altitude areas, frost ends everywhere and the temperature rises in waves. The prevailing wind direction during the season gradually changes from north to south, and the number of rainy days increases. Around the vernal equinox, cold air passes through, and strong winds from the northeast occur for a short period of time. The temperature is lower than 12°C, and it is mostly rainy weather. April and May are the rainy season, with temperatures rising to above 20°C and rainy days increasing to more than 20 days. However, cold air still occasionally hits the south, and "May cold" (lasts for 3 days, temperature ≤20℃) often occurs at this time. Summer: The rainy season ends, and the monthly average temperature rises to above 25°C. After entering July, it sometimes reaches above 35°C, and the weather is hot. During the season, there are mostly southeasterly or southwesterly winds, frequent typhoons, and localized thundershowers or typhoon rains. The temperature is high, the sun is abundant, and the evaporation is large. It is a relatively dry and hot period of the year. Autumn: At this time, the summer monsoon turns to winter monsoon, the temperature gradually drops, the rainfall decreases significantly, and the weather is sunny and refreshing. In some years, the subtropical high pressure is strong and small strands of cold air cannot move south easily, resulting in "autumn tiger" weather. In late September, strong cold air passed through, causing "autumn cold" (temperature ≤ 20°C). After November, the first frost has been seen in inland mountainous areas. Winter: The temperature drops sharply and frost becomes more common. Ice and snow appeared in a few places inland, and rain was scarce. January is the coldest month, with the average monthly temperature below 10°C regardless of whether it is in mountainous areas or along the coast.