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>From: mljacobs <address@hidden> >Organization: UCAR/Unidata >Keywords: 200309102217.h8AMHeLd023414 >Hello, >I was wondering if there is a way to get a rainfall rate from using the >difference in 1-hour precip. in GEMPAK. The files are updated every 6 min. >Resulting in the amount of rainfall in 6 minutes. I have the level III radar >data from NCDC. >Am I going about this the right way or do you have another suggestion? >Thanks for your time >Matt Jacobs (KU) > Matt, The NIDS Level III products are 16 value images and not actual data values. The 16 values therefore represent a range of precipitation values, so trying to do mathematical differencing is not likely to be accurate. The products are generated from the PUP using Z to R relationships assuming a droplet size distribution), so you can use the reflectivity product (again these are 16 binned data values) as an approximation to instantaneous rainfall rate. Otherwise, you would have to do a Z to R conversion from level 2 data values. Steve Chiswell