TITLE:
Analysis of a Large-Scale Strong Convective Weather under a Weak Water Vapor Condition in Shanxi, China in Spring
AUTHORS:
Jingyu Hao, Guixiang Zhao, Jie Zhu, Yang Wang, Yanzhi Ma, Yuanyuan Guo
KEYWORDS:
Strong Convection, Mesoscale Boundary Layer Front, Potential Vorticity, Environmental Characteristics, Maintenance and Evolution
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.11 No.7,
July
20,
2023
ABSTRACT: This article uses NCEP 1° × 1° grid point reanalysis
data, conventional meteorological
observation data, FY2G satellite TBB data, radar combined reflectivity
data, ground-encrypted automatic station observation data, etc., through the synoptic diagnostic analysis method for a
comprehensive analysis of a large-scale underreporting of a strong
convective weather process under weak water vapor conditions on the 13th April
2017. The results show that the severe convective weather process is affected
by the short-wave disturbance in the northwesterly airflow, triggered by the
uplift of the westerly trough, the mid-low shear line and the mesoscale front
of the boundary layer in the dry northwest. The jet stream is also an important system for the
development of this strong convective weather. In the case of weak water vapor
and energy conditions, if there is strong
dynamic uplift, vertical wind shear and large temperature differences, strong convection can still occur; the convection
occurrence area corresponds to the high
potential vorticity abnormal area. The movement speed and direction of
the cloud cluster are also consistent with the movement of the high potential
vorticity anomaly area; the potential vorticity anomaly will cause the cyclonic
circulation to increase, and the upward movement will also increase, which is
conducive to the development of strong convective weather. According to the position of the dew point front in the β
mesoscale, the ground cold pool corresponds to the small value area of the convective
cloud cluster TBB. The front of the cold pool is accompanied by a mesoscale
ground convergence line, and the uplift is strengthened, which is conducive to
the development and forward movement of thunderstorms; the outflow of the cold
pool is guided by 700 hPa. When the wind
direction is the same, the movement speed will increase, and the stronger
the outflow, the faster the movement speed.