Based on conventional meteorological data and NCEP 1°×1° DEG reanalysis data, reasons for a regional rainstorm in Fuzhou, Jiangxi Province on May 27, 2013 was analyzed from the aspects of weather situat...Based on conventional meteorological data and NCEP 1°×1° DEG reanalysis data, reasons for a regional rainstorm in Fuzhou, Jiangxi Province on May 27, 2013 was analyzed from the aspects of weather situation, influencing systems, water vapor, dynamic and thermal instability. The results showed that the regional rainstorm happened in the warm area while the Jianghuai cyclone moved eastwards, and it was a short-dura- tion strong convective rainstorm. Jianghuai cyclone, 500 hPa trough, low vortex and southwesterly jet were the main influencing systems of the rain- storm. The precipitation was mainly the result of release of convective unstable energy in the lower troposphere. MPVl was negative in the lower troposphere and positive in the middle and upper troposphere. Moist potential vorticity in the upper troposphere moved downwards, which was ad- vantageous to the release of the unstable energy and then increased precipitation. The negative moist potential vorticity center in the lower tropo- sphere can reflect the position and intensity of the rainstorm, and the intensity and duration of precipitation were consistent with the increase of the negative MPVl. The distribution of MPV2 showed that as atmospheric baroclinicity increased, heavy rain always occurred in the lower troposphere where baroclinicity was strong. The areas with negative baroclincity in the lower troposphere matched with rainstorm center very well.展开更多
基金Supported by the Special Project for Forecasters of China Meteorological Administration(CMAYBY2014-035)
文摘Based on conventional meteorological data and NCEP 1°×1° DEG reanalysis data, reasons for a regional rainstorm in Fuzhou, Jiangxi Province on May 27, 2013 was analyzed from the aspects of weather situation, influencing systems, water vapor, dynamic and thermal instability. The results showed that the regional rainstorm happened in the warm area while the Jianghuai cyclone moved eastwards, and it was a short-dura- tion strong convective rainstorm. Jianghuai cyclone, 500 hPa trough, low vortex and southwesterly jet were the main influencing systems of the rain- storm. The precipitation was mainly the result of release of convective unstable energy in the lower troposphere. MPVl was negative in the lower troposphere and positive in the middle and upper troposphere. Moist potential vorticity in the upper troposphere moved downwards, which was ad- vantageous to the release of the unstable energy and then increased precipitation. The negative moist potential vorticity center in the lower tropo- sphere can reflect the position and intensity of the rainstorm, and the intensity and duration of precipitation were consistent with the increase of the negative MPVl. The distribution of MPV2 showed that as atmospheric baroclinicity increased, heavy rain always occurred in the lower troposphere where baroclinicity was strong. The areas with negative baroclincity in the lower troposphere matched with rainstorm center very well.
