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# pcp\_ave

The average or mean total monthly precipitation is calculated as

$$
R\_{mon}=\frac{∑*{d=1}^N\*R*{day,mon}}{yrs}
$$

where $$R\_{mon}$$ is the mean monthly precipitation (mm H2O), $$R\_{day,mon}$$ is the daily precipitation for day $$d$$ in month $$mon$$ (mm H2O), $$N$$ is the total number of records in month $$mon$$ used to calculate the average, and $$yrs$$ is the number of years of daily precipitation records used in calculation.