On the basis of comprehensive analysis on weather background and main influencing system of rainstorm formation,using NCEP reanalysis data,rainfall data of Shaoyang ground regional automatic station,a new generation o...On the basis of comprehensive analysis on weather background and main influencing system of rainstorm formation,using NCEP reanalysis data,rainfall data of Shaoyang ground regional automatic station,a new generation of Doppler weather radar product information,etc.,high-altitude weather situation and physical formation mechanism of local double-cyclone type of rainstorm process with easterly wave in Shaoyang area on August 14,2016 were analyzed in detail,to find out prophase signal features which had indicating significance for rainstorm forecast. The results showed that:(1) the position of zonal subtropical high pressure in east-west direction was the necessary condition for the formation of easterly wave.(2) The rainstorm formation was closely related to double tropical depressions acting in the south of subtropical high pressure,and westward movement of easterly wave over 500 hPa and low-pressure inverted trough at low layer were main impact systems of the rainstorm.(3) Continuous flow of water vapor from the South China Sea to northwest was the source of water vapor required by this rainstorm.(4) Numerical prediction model products had certain guiding significance for forecasting the heavy precipitation,with important reference value.(5) Doppler radar products had strong forecasting ability in the nowcasting of rainstorm falling zone,which was an important measure of correcting forecast errors.展开更多
基金Supported by Forecasters' Special Project of Hunan Meteorological Bureau(XQKJ16C008)
文摘On the basis of comprehensive analysis on weather background and main influencing system of rainstorm formation,using NCEP reanalysis data,rainfall data of Shaoyang ground regional automatic station,a new generation of Doppler weather radar product information,etc.,high-altitude weather situation and physical formation mechanism of local double-cyclone type of rainstorm process with easterly wave in Shaoyang area on August 14,2016 were analyzed in detail,to find out prophase signal features which had indicating significance for rainstorm forecast. The results showed that:(1) the position of zonal subtropical high pressure in east-west direction was the necessary condition for the formation of easterly wave.(2) The rainstorm formation was closely related to double tropical depressions acting in the south of subtropical high pressure,and westward movement of easterly wave over 500 hPa and low-pressure inverted trough at low layer were main impact systems of the rainstorm.(3) Continuous flow of water vapor from the South China Sea to northwest was the source of water vapor required by this rainstorm.(4) Numerical prediction model products had certain guiding significance for forecasting the heavy precipitation,with important reference value.(5) Doppler radar products had strong forecasting ability in the nowcasting of rainstorm falling zone,which was an important measure of correcting forecast errors.
