Evaluation of Three High-resolution Operational Weather Forecast Models for Precipitation in Guizhou Province During the Rainy Season 2023
Due to the complex terrain,precipitation in Guizhou is difficult to forecast accurately.A comprehensive evaluation of the forecast products of high-resolution regional models is one of the keys to improve the model forecast performance.Based on the hourly precipitation data from 1 560 stations in Guizhou Province during the rainy season(from 15 April to 15 October)in 2023,the forecast abilities of three high-resolution regional models(CMA-MESO,CMA-GD,CMA-SH)are evaluated in detail in terms of TS score,precipitation frequency,intensity and peak period of precipitation in Guizhou.The evaluation results of the models on the daily precipitation forecasts show that the regional mean daily precipitation and frequency in the rainy season are overestimated by all three models.The large-value center of the precipitation can be predicted by all models basically,but the location of the precipitation center is by east and north relative to the observation.The CMA-GD shows a higher TS in the forecasts of moderate rain to rainstorm,while CMA-MESO is the worst for all precipitation magnitudes in TS.The deviation time of precipitation and frequency forecast is different for each model based on the forecast evaluation of 6 h accumulated precipitation in the 60 selected heavy precipitation days.The negative precipitation deviations of CMA-MESO forecast are mostly seen in the afternoon,while the forecasts by CMA-GD and CMA-SH exhibit the largest positive deviations in the morning.Higher precipitation frequency is mostly observed in the northeastern part(daytime)and western part(nighttime)of Guizhou.CMA-GD performs better in forecasting the spatial and temporal variation of precipitation frequency,but the other two model forecasts have larger deviations.In terms of the precipitation peak time on heavy precipitation days,the models can forecast more accurately for northeastern Guizhou,while the forecast time of peak precipitation by the three models in the southeast of Guizhou is at night rather than in the daytime from observation.To sum up,CMA-GD forecast shows the best TS for daily precipitation on average and can correctly reproduce the diurnal variation of precipitation.Furthermore,the integrated evaluation method based on precipitation amount,frequency,intensity and diurnal variation is helpful for correctly understanding the biases of model forecasts with complex terrains.
NETL
NSTL
万方数据
