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# 2:1.1.1.2 Antecedent Soil Moisture Condition

SCS defines three antecedent moisture conditions: I—dry (wilting point), II—average moisture, and III—wet (field capacity). The moisture condition I curve number is the lowest value the daily curve number can assume in dry conditions. The curve numbers for moisture conditions I and III are calculated with the equations:

$$CN\_1=CN\_2-\frac{20\*(100-CN\_2)}{(100-CN\_2+exp\[2.533-0.0636\*(100-CN\_2)])}$$                                                                                  2:1.1.4

$$CN\_3=CN\_2*exp\[0.00673*(100-CN\_2)]$$                                                                                             2:1.1.5

where $$CN\_1$$ is the moisture condition I curve number, $$CN\_2$$ is the moisture condition II curve number, and $$CN\_3$$ is the moisture condition III curve number.