今春河南省为何大风频发

Core Viewpoint - The article discusses the unusual frequency of strong winds in Henan Province during April, attributed to climatic factors such as the La Niña phenomenon and abnormal cold air activity [3][4][5]. Group 1: Weather Patterns - Henan Province has experienced strong winds exceeding level 10, with occurrences 2.9 times higher than the average of the past five years [3]. - The La Niña phenomenon, although weakening, has contributed to unstable weather patterns, leading to strong winter winds and delayed precipitation [4]. - The Siberian high pressure has been unusually strong, facilitating the southward movement of cold air, resulting in frequent strong winds in North China [5]. Group 2: Wind Speed and Impact - The strongest winds were recorded between April 11 and 13, with gusts reaching levels 10 to 12, and some areas experiencing winds as high as 15 levels, with a maximum speed of 46.8 meters per second [6]. - The article provides a scale of wind levels, indicating the potential damage and effects associated with different wind speeds, emphasizing the dangers of winds above level 6 [7]. Group 3: Agricultural Risks - As of May 4, 51% of monitoring stations in Henan reported drought conditions, with soil moisture deficiency worsening, particularly in five cities where over 70% of stations indicated low moisture [8]. - A warning was issued regarding the risk of dry hot winds affecting wheat during its grain-filling period, with temperatures expected to exceed 35°C from May 11 to 13 [8].