Parameterization of convective clouds mesoscale convective systems, and convective-generated cirrus. Final report, September 15, 1990--October 31, 1993

Abstract Precipitating systems are analyzed during a dust event from 9 to 14 June 2006 over northern Africa. A common analysis is applied to satellite observations and two Meso-NH simulations: one convection permitting (grid spacing x = 2.5 km) and the other with parameterized convection (x = 20 km). The precipitating systems are identified as cloud objects and classified as deep convective clouds (DCCs) or other clouds according to their infrared signature. Large DCCs [hereafter named mesoscale convective systems (MCSs)] are tracked, characterized in terms of precipitation and thermodynamic profiles, and analyzed in southern West Africa (SWA), central Africa, and Ethiopia. Precipitation is mostly observed along 0°–15°N, with 71% of the total precipitation produced by all DCCs and 55% by long-lived MCSs. It shows a marked diurnal cycle with a peak in the evening, mainly due to long-lived MCSs, which are characterized by an increase in size, zonal speed, and duration from east to west, with the largest, fastest, and longest-lived ones found over SWA. This is due to an enhanced African easterly jet (AEJ) and monsoon flow leading to stronger shear and greater conditional instability. The simulation with parameterized convection fails to distribute precipitation correctly. The convection-permitting simulation captures most of the observed precipitation features, but lacks the increase in organization of the long-lived MCSs over SWA. Excess moisture in a too zonal AEJ flow suggests that the long-lived MCSs in SWA are poorly located with respect to African easterly waves. The convection-permitting model improves the representation of precipitation but without fully resolving the long-lived MCSs.

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WRF simulations of mesoscale convective systems at convection-allowing resolutions

10.31274/etd-180810-2826 ◽

2011 ◽

Author(s):

Jeffrey Dean Duda

Keyword(s):

Mesoscale Convective Systems ◽

Convective Systems ◽

Mesoscale Convective

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The role of the convective ?trigger function? in numerical forecasts of mesoscale convective systems

Meteorology and Atmospheric Physics ◽

10.1007/bf01025402 ◽

1992 ◽

Vol 49 (1-4) ◽

pp. 93-106 ◽

Cited By ~ 119

Author(s):

J. S. Kain ◽

J. M. Fritsch

Keyword(s):

Mesoscale Convective Systems ◽

Convective Systems ◽

Trigger Function ◽

Mesoscale Convective

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A five-year climatological lightning characteristics of linear mesoscale convective systems over North China

Atmospheric Research ◽

10.1016/j.atmosres.2021.105580 ◽

2021 ◽

Vol 256 ◽

pp. 105580

Author(s):

Dongxia Liu ◽

Mengyu Sun ◽

Debin Su ◽

Wenjing Xu ◽

Han Yu ◽

...

Keyword(s):

North China ◽

Mesoscale Convective Systems ◽

Convective Systems ◽

Mesoscale Convective

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An Observational Study of Mesoscale Convective Systems with Heavy Rainfall over the Korean Peninsula

Weather and Forecasting ◽

10.1175/waf912.1 ◽

2006 ◽

Vol 21 (2) ◽

pp. 125-148 ◽

Cited By ~ 33

Author(s):

Hyung Woo Kim ◽

Dong Kyou Lee

Keyword(s):

Observational Study ◽

Korean Peninsula ◽

Wind Shear ◽

Heavy Rainfall ◽

Vertical Wind Shear ◽

Vertical Wind ◽

Mesoscale Convective Systems ◽

Low Level ◽

Convective Systems ◽

Mesoscale Convective

Abstract A heavy rainfall event induced by mesoscale convective systems (MCSs) occurred over the middle Korean Peninsula from 25 to 27 July 1996. This heavy rainfall caused a large loss of life and property damage as a result of flash floods and landslides. An observational study was conducted using Weather Surveillance Radar-1988 Doppler (WSR-88D) data from 0930 UTC 26 July to 0303 UTC 27 July 1996. Dominant synoptic features in this case had many similarities to those in previous studies, such as the presence of a quasi-stationary frontal system, a weak upper-level trough, sufficient moisture transportation by a low-level jet from a tropical storm landfall, strong potential and convective instability, and strong vertical wind shear. The thermodynamic characteristics and wind shear presented favorable conditions for a heavy rainfall occurrence. The early convective cells in the MCSs initiated over the coastal area, facilitated by the mesoscale boundaries of the land–sea contrast, rain–no rain regions, saturated–unsaturated soils, and steep horizontal pressure and thermal gradients. Two MCSs passed through the heavy rainfall regions during the investigation period. The first MCS initiated at 1000 UTC 26 July and had the characteristics of a supercell storm with small amounts of precipitation, the appearance of a mesocyclone with tilting storm, a rear-inflow jet at the midlevel of the storm, and fast forward propagation. The second MCS initiated over the upstream area of the first MCS at 1800 UTC 26 July and had the characteristics of a multicell storm, such as a broken areal-type squall line, slow or quasi-stationary backward propagation, heavy rainfall in a concentrated area due to the merging of the convective storms, and a stagnated cluster system. These systems merged and stagnated because their movement was blocked by the Taebaek Mountain Range, and they continued to develop because of the vertical wind shear resulting from a low-level easterly inflow.

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