Calculate precipitation from WRF model output From WRF output file,     

I find 3 variables related to the precipitation (unit: mm)

1. Precipitation    


variable name: pr     
unit:$kg/(m^{2}s^1)$     
variable: RAINC+RAINNC     
comments: $dt(RAINC+RAINNC)/DT$


2. Max hourly precipitation rate    


variable name: prhmax     
unit:$kg/(m^{2}s^1)$     
variable: RAINC, RAINNC or RAINMAX1Hclwrf   
comments: $MAX(dtsum()/DT)$


3. Convective precipitation    


variable name: prc     
unit:$kg/(m^{2}s^1)$     
variable: RAINC 
comments: $d_t(RAINC)/DT $       


My task:      


  Summarize the amount of days which precipitation > 0.254 mm       


What variable should I use for further analysis?   

Any advice would be appreciated.
Use (1) Precipitation, as it is the sum of convective and non-convective precipitation, integrate it over one day, voilà.

converting [$kg/(m^2 s)$] (precip):
$$ precip [kg/(m^2 s)] \cdot dt [s] \cdot \frac{1}{ \rho_w [kg/(m^3)]} \cdot 1000 [mm/m] = total\_precip [mm]$$

where $\rho_w$ is the density of water.

Practically the last two factors cancel.