12-Hour Storm Distribution

[FINK_RB_PE]

I am trying to find some information on the 12-hour storm event for the maximum possible flood for an emergency action plan. I am required to look at the 6, 12, and 24 hour storm. All of the programs I have only discuss the 6 and 24 hour event.

Also, just a general hydrology question. If the time of concentration is less than 6 hours won't the 24 hour storm produce a greater peak flow if the precipitation for the 24 hour storm is greater than the 12 hour event?

Any help would be appreciated.

 

[Dleg]

I don't know..... using TR-55 (official NRCS windows version), you only get the 24 hour storm option. Unless there is an option buried deep in the program. Ask around and dig up your local rainfall data - chances are if an "authority" is asking for the 6 hour storm data, it must be based on some rule somewhere, and that "authority" should be able to direct you to where to find the data.