基于加密站资料的青藏高原强对流天气预报分析

Analysis of strong convective weather forecast over Qinghai-Tibetan Plateau based on data of encrypted station

利用常规气象观测、西宁多普勒雷达、加密自动站、NCAR1°×1°再分析等资料,对2016年8月18日清晨发生在青海省东北部的一次强对流天气进行分析。结果表明,副热带高压外围的西南暖湿气流与东移扩散南下的冷空气在青海省东北部交汇是此次强对流天气发生的主要成因;雷达回波表现为弓形回波,伴有持久的中气旋,最强回波可达65 dBz以上,顶高17 km以上,VIL在30~40 kg/m^2,是典型的超级单体特征;气压、温度、相对湿度均出现了不连续线,强降水发生时出现气压上升、相对湿度突升,温度突降特征,气压与湿度呈同位相变化,与温度的变化位相相反,强降水发生在辐合线的附近。

Using the conventional meteorological observation, Xining Doppler radar, automatic station, NCAR1°×1°, reanalysis data for use, a strong convective weather was analysised in the northeast of Qinghai province, on the morning of August 18,2016. The results showed that the southwest of subtropical high and cold air eastward southward in the northeast of Qinghai province intersection was the main cause of the convective weather;Radar echo was accompanied by persistent bow echo,mesocyclone, the strongest echo up to 65 dBz at the top, above 17 km, VIL was 30~40 kg/m^2, which was the typical feature of supercell;There are discontinuities in air pressure, temperature and relative humidity. When heavy precipitation occurs,there is a rise in pressure, a sudden rise in relative humidity, and a sudden drop in temperature. The pressure and humidity changed in the same phase, contrary to the temperature change phase, strong precipitation occurred in the vicinity of the convergence line.