<p>Is there any equation I can use to determine curve number as a function of the antecedent precipitation? I am aware of three sets of curve numbers for dry, wet and normal conditions. I was looking at a numerical expression, where I can adjust the curve number based on current moisture conditions (expressed using antecedent precipitation as a proxy).</p>
<p>Adding some background on Curve Number:</p>
<p>Curve number is an empirical parameter used for determining the runoff. It depends upon the soil group, land cover and any treatment applied to the soil.</p>
<p>Here is the wikipedia article on Curve Number:
<a href="https://en.wikipedia.org/wiki/Runoff_curve_number" rel="nofollow noreferrer">https://en.wikipedia.org/wiki/Runoff_curve_number</a></p>

CC BY-SA 4.0
2023-05-20T09:46:12.720Z
Perhaps worth clarifying for most of us a quick link/idea of what curve numbers are?  Something used for flooding values??
JeopardyTempest
CC BY-SA 4.0
2023-05-25T20:32:20.527Z
@JeopardyTempest I edited my question and added some details. Thanks!
user1889930
CC BY-SA 4.0
2023-05-27T08:15:32.053Z
Runoff curve number is just a parameter depending in ground infill and ground clasification, so no relation with antecedent rainfall. If you have values of current moisture, or you can approx by precious precipitation, then you can work on the runoff equation. As more moisture, you will get more runoff flow, but CN is not changing due to the moisture.
David García Bodego
<climate-change><climate><hydrology><urban-climate>
Curve number adjustment based on antecedent rainfall
user1889930
# Curve number adjustment based on antecedent rainfall

(Asked by: username_0 on 2023-05-19)

Is there any equation I can use to determine curve number as a function of the antecedent precipitation? I am aware of three sets of curve numbers for dry, wet and normal conditions. I was looking at a numerical expression, where I can adjust the curve number based on current moisture conditions (expressed using antecedent precipitation as a proxy).

Adding some background on Curve Number:

Curve number is an empirical parameter used for determining the runoff. It depends upon the soil group, land cover and any treatment applied to the soil.

Here is the wikipedia article on Curve Number:
<https://en.wikipedia.org/wiki/Runoff_curve_number>

**Tags:** climate-change, climate, hydrology, urban-climate

> **Comments:**
> **username_1**: Perhaps worth clarifying for most of us a quick link/idea of what curve numbers are?  Something used for flooding values??  
> **username_0**: @username_1 I edited my question and added some details. Thanks!  
> **username_2**: Runoff curve number is just a parameter depending in ground infill and ground clasification, so no relation with antecedent rainfall. If you have values of current moisture, or you can approx by precious precipitation, then you can work on the runoff equation. As more moisture, you will get more runoff flow, but CN is not changing due to the moisture.  

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## 0 answers

