Abstract: The SWC-WARMS predictions of the 24h rainfall, related physical quantities initiated at 20:00 BST and the actual precipitation in Chengdu from June to September of 2014 are used to figure the traditional forecast skill scores for different precipitation levels and analyze the thresholds value of the heavy precipitation (over 25mm) physical quantities by using neighborhoods method to build the corresponding relations between high resolution mode and the sparse site. The inspection results are as follows: The model has a better effect on the appearing of rainfall; Threat Score (TS) of light rain is relatively high, followed by moderate rain, and then heavy rain; Meanwhile, mixed TS of storm rain and above is 11.6%, which has reference value to some extent. Analysis of corresponding physical quantities corresponding to heavy rain shows that SWC- WARMS has certain forecasting ability, but the forecast of magnitude and falling area are relatively poor; the thresholds of physical quantities of the first two precipitation cases all satisfy the conditions of storm rain and above.