Abstract: Using hourly precipitation data originated from digital information processing of recording paper data from 53 national weather stations during 1971-2003 and rainfall observation data from automatic weather stations during 2004-2014 in Liaoning province,the spatial-temporal characteristics of April -October short-time strong precipitation (STSP) in Liaoning province were investigated.The results show that the spatial distribution of the STSP frequencies during the period from 1971 to 2014 is consistent with the spatial distribution of the total annual precipitation,both are larger in the east and lower in the west of Liaoning province and have a close corresponding relation with the terrain of Liaoning province and the wind direction of the southwest low-level jet.More specifically,the annual frequencies of STSP which have well correspondence with a waterlogging-drought change in Liaoning province dramatically vary between 1.5 and 3.5 during 1971-2014.The STSP concentrates in July and August in Liaoning province and is dominantly distributed in Dandong.Furthermore,the frequency of ten-day STSP firstly increases and then decreases during June to August and its peak value appears in last July.At the same time,the change trend of STSP frequency varies among different areas.Moreover,the diurnal variation of STSP frequency has the feature of territoriality,under the influence of the terrain and the diurnal change of the low-level jet and is not obvious in the north and the westernmost of Liaoning province.The STSP tends to occur over the period from the middle of the night to the morning in the south of Liaoning province while it occurs more frequently in the afternoon in the rest of Liaoning province.

Key words: Short-time strong precipitation, Terrain, Low-level jet