Open AccessAnalysis and forecasting of heavy-rainfall event by strong convection
Author(s) -
Lingkun Ran,
Yuepeng Zhou,
Wenxia Yang
Publication year - 2011
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.60.099201
Subject(s) - baroclinity , advection , convection , troposphere , precipitation , vorticity , atmospheric convection , climatology , wind shear , perturbation (astronomy) , severe weather , environmental science , atmospheric sciences , physics , meteorology , geology , vortex , wind speed , thermodynamics , storm , quantum mechanics
For the case of severe convection occurring in the southern region of North China on July 8, 2009, the three dynamical factors, namely, vertical component of convective vorticity vector, moist thermodynamic advection parameter and wave-activity density are diagnosed. The result shows that the anomalous-value regions of dynamical factors are located mainly in middle and lower troposphere over the strong precipitation area. Since the dynamical factors can effectively describe the synthetical characteristics of strong convective system, such as vertical shear of horizontal wind, advection of potential temperature, vorticity perturbation and baroclinicity of moist atmosphere, they correspond to the observation of 6-h accumulative rainfall in horizontal distribution patterns. Using the 6-h, 12-h, 18-h and 24-h forecasting dataset of U.S. NCEP/NCAR 0.5-Degree GFS, the dynamical factors are calculated to analyze their indications of precipitation forecasting during a longer period. The results show that during June 2 – Oct 1, 2009, the 6-h, 12-h, 18-h and 24-h forecasted dynamical factors each have an indication of strong precipitation. The moist thermodynamic advection parameter suggests that the precipitation is best among the three dynamical factors.