The daily electricity consumption, daily peak loads, daily valley loads and the meteorological data of Henan, Hubei, Hunan and Jiangxi from May to September 2011 to 2015 are used to investigate the effect of the sunny hot weather on electric loads. The results show that the hot weather lasted more than 3 days influences the increase of electric loads obviously, especially in Hubei. The temperature has distinct significance to the growth of electric loads, when the air temperature is greater than or equal to the temperature threshold of Accumulated Temperature Effect. The initial sensitive value of daily average temperature, daily maximum temperature and daily minimum temperature is 31 ℃, 36 ℃ and 27 ℃ respectively in Hunan, and the strong sensitive value is 32 ℃, 39 ℃ and 29 ℃. The multiple regression forecasting model of electric meteorological loads based on the accumulated temperature effects is tested from May to September in 2016 The results show that the average relative errors of four provinces are confined to 5%, which has good reference value to the electric power dispatching of the central China while correcting the forecast results properly according to specific weather conditions.