85th and 95th Percentile Rainfall

These layers represent the spatial distribution of the 85th and 95th percentile, 24-hour rainfall within the County of Los Angeles.

Rainfall gages throughout the County were selected based on spatial distribution and rainfall record length to determine the 85^th and 95^th  percentile, 24-hour rainfall.  The 85^th and 95^th percentile, 24-hour rainfall can be used to determine the stormwater quality design volume per DPW’s Low Impact Design Manual.

You can also check out this data on an interactive map located here: http://dpw.lacounty.gov/wrd/hydrologygis/ 

Data Downloads

Click here to download the LA County 95th_Percentile_Isohyet

Click here to download the LA County 85th_Percentile_Isohyet