NRCS2-Rain Event Lookup Table
The NRCS2-Rain table (added in HydroCAD 10.2-4b), provides the latest NRCS rainfall database based on Atlas-14 Volume 10, and implements new rainfall distributions including NOAA10 (N10), NV, SW, TX, CA, and HI.
NRCS2-Rain is based primarily on the NRCS WinTR-55 v2 release, and generally supersedes the previous NRCS-Rain table.
The intent of this
table is to accurately represent the rainfall data published by NRCS at this
time. If updated data becomes available from NRCS, we will endeavor to
provide that information by way of a new lookup table, rather than making
changes to the original NRCS2-Rain table.
If
new rainfall data is published by individual states, that information will
generally be incorporated by the addition of a separate lookup table, such as
NJ-2023-Rain.
If you have local rainfall data
that differs from the values in the lookup table, feel free to edit your event
definitions accordingly.
Rainfall Usage by State
This table summarizes the rainfall distributions used for each state in the NRCS2-Rain event lookup table. As always, check your local stormwater regulations for exact requirements, which may differ from the NRCS recommendations discussed on this page.
| Distributions | States Used |
| Type-I | AK |
| Type-IA | AK OR WA |
| Type-II | CA ID MO MT OR PR WA WY |
| Type-III | (none) |
| CA_1/2/3/4/5/6 | CA |
| HI_1/2/3/4/5/6 | HI |
| MSE_1/2/3/4/5/6 | AL AR CO FL GA IA KS LA MI MN MS NE OK SD WI |
| ND_2/3/4 | ND |
| Nevada_NB/S/W (NV) | NV |
| NOAA_A/B/C/D | DC DE MD IL IN KY MD NC NJ OH PA SC TN VA WV |
| NOAA10_A/B/C/D (N10) | CT MA ME NH NY RI VT |
| NRCC_A/B/C/D | (none) |
| PR_VI_1/2/3/4 | PR VI |
| SW_1/2/3/4/5 | AZ NM UT |
| TX_A/B/C/D | TX |