In order to clarify the synoptic meteorology and low-level circulation characteristics of orographic precipitation in northeastern Tibetan Plateau (referred as TP), numerical simulation of a precipitation case that happened in Qilian Mountains on August 12–13, 2019 was conducted using the Weather Research and Forecasting (WRF) model in this paper. The results show that WRF model can roughly capture the timing and location of the orographic precipitation. During the period, a weak trough and a weak ridge were found behind a large-scale trough at 500 hPa at the initial and continuation phases primarily due to the effect of complicated topography to provide a beneficial circulation background at high altitudes. The extinction of this circulation pattern and northwesterly after the large-scale trough leaded to the extinction of the precipitation.

中文翻译：

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青藏高原东北祁连山地形降水环流特征数值模拟


为明确青藏高原东北部地形降水的天气气象和低层环流特征，本文采用天气研究与预报（WRF）模式对2019年8月12—13日祁连山发生的一起降水事件进行了数值模拟。结果表明，WRF 模型可以大致捕捉地形降水的时间和位置。在此期间，在初期和延续期，在 500 hPa 的大范围槽后发现了弱槽和弱脊，这主要是由于复杂的地形影响，在高海拔地区提供了有益的环流背景。这种环流模式的消亡和大范围槽之后的西北走向导致了降水的消亡。