storm pattern

[engrsalah]

i have daily rain fall data for last 30 years. in which i extract maximum daily data in each year. now how to find 24 hour rain fall pattern.or simply how to find 24 hr storm pattern for hydro graph generation.

 

[psmart]

Daily rainfall data (i.e. 1 reading for every 24-hours) is not sufficient to create a 24-hour rainfall distribution. To create a 24-hour distribution would typically need depth observations at 5-10 minute intervals. Based on that data you could derive a set of IDF curves, which could in turn be used to generate a 24-hour synthetic rainfall distribution.

Peter Smart
HydroCAD Software

http://www.hydrocad.net

 

[engrsalah]

is huff distribution is applicable for here in pakistan?

 

[psmart]

Not likely. Do you have any IDF data?

Peter Smart
HydroCAD Software

http://www.hydrocad.net

 

[psmart]

Have you tried a Google search? I'm seeing some potentially useful hits.

Peter Smart
HydroCAD Software

http://www.hydrocad.net

 

[engrsalah]

no i have not any IDF data.
and yes i thoroughly search in google. but not succeeded.

 

[psmart]

I'm getting plenty of likely candidates when I search for "pakistan idf rainfall"

https://www.google.com/search?q=pakistan+idf+rainfall

Peter Smart
HydroCAD Software

http://www.hydrocad.net

 

[elev8848]

Hi Engr Salah,
1) Is your data recorded for reach 24 hour?
2) Is the rainfall similar to any nearby Cities where IDF curve is available?
3) Are you trying to create a storm hyetograph?
3) Is the hydrograph needed for river basin or small urban catchment?
Thanks

 

[engrsalah]

elev8848
1) Is your data recorded for reach 24 hour? yes it is 24 hr data.
2) Is the rainfall similar to any nearby Cities where IDF curve is available? i dont certain about this. however it is difficult to exists
3) Are you trying to create a storm hyetograph? yes. actually i am trying to find 1000 year return period. for which i want to distribute it and create hydro-graph.
3) Is the hydrograph needed for river basin or small urban catchment? yes it is needed for river basin.
Thanks

 

[cadsync]

Hello Engr Salah,

Do you have access to sub-daily satellite rainfall data over Pakistan?
I've been able to use Tropical Rainfall Measuring Mission (TRMM) rainfall estimates to generate IDF curves here in Africa (Nigeria).
TRMM has 3 hourly rainfall estimates, so just do a google search and see if you have such that covers Pakistan, else you will have to look into ways of "downscaling" the 24hr IDF intensity to lower durations using the "simple scaling" method.

Regards

Out of the mire...a spectacle of perfection. #TheLotusConstruct