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154 sqmi Slate Creek at Wellington, KS

Continuous HEC-HMS Nexrad Radar  Rainfall-Runoff with Forecast Comparisons in Real-Time
With Radar Hourly Ratio Adjustments
and Snowmelt Provided by GetRealtime

Jan 1, 2019 to ... currently running.



































The Witchita ICT radar was down for 3 weeks beginning Feb 4, 2019 as part of their Service Life Extension Program:  https://www.weather.gov/ict/RadarPedestalReplacement

The VNX radar 53 miles away instead of ICT 21 miles for that period and has been returned to ICT.


Current NOAA N0R radar lite gif above with Slate Creek Basin overlay.  Below is zoomed N0Q hi-res radar, Wundergages, and adjusted N0Q at watersheds.  Note that the raw N0Q radar here almost always shows "ground clutter" because of being so close to the radar site. Ground clutter (0.05" to 0.1" a day) is just another simple matter that rain gage adjustment removes.  No rain at the rain gages for the hour then no radar rain.  Beginning Oct 26, 2020 the MRMS radar product A2M is used with out rain gage adjustment.  There isn't a heated gage in the area apparently so I'll try the A2M but results for other locations in the past were pretty bad.  We will see how it does here.


GetRealtime can automate gage adjusted radar rainfall and snowmelt for HEC-HMS model and shell HMS and retrieve the HMS output in realtime.  I am NOT experienced with HMS setups for use in real-time for continuous modeling so this is probably more of how my GetRealtime runoff compares to the USGS gage than a very well performed HMS setup comparison.  This study does show that HMS can be used by more experienced HMS modelers so I'll leave that part up to you.


The Slate Creek basin was subdivided into 3 basins and both GRT (GetRealTime) and HMS used the same channel info for Muskingum-Cunge routings.  HMS does not seem to route very well and is probably due to my operater screw ups.  Again, this study shows HOW to operate HEC-HMS in realtime and not very much on how to setup HMS.  I gave it my best shot.  My GRT uses my continuous soil moisture adjsted SCS Curve Number method.  HMS uses just the standard SCS Curve Number of 64 for the 3 subbasins with simple 0.03" leaf loss and monthly ET values for doing HEC stuff to the losses what ever that is.  My GRT model uses the same monthly ET values but distribued on an hourly basis over the year (ET is computed w and w/o gaged Solar for display only here but could have also been used.



Last model run info from database as text each run (GetFromAccessNOW.exe):     




Current automated graphs and radar (updated when runoff)


Radar ratio adjusted rainfall and Wundergages (pink is second source referred to)  :

Stage from GRT green, USGS gage pink, & HMS (3rd source HMS is orange):

Subbasin runoff (2nd source is pink, 3rd is orange):

Wundergages and radar ratio adjustment:

Meteorlogical data from Wundergages for snowmelt and evapotranspiration used by GRT:

Snowpack and soil moisture info used by GRT:


Pearson III Annual Peak Flow Probability Distribution:



Past runoff comparisons for the 3 subs and routed basin runoff:










Radar A2M Snow Precip and Snowmelt Runoff with Un-heated Rain Gage Delayed Melting:


Important Note:  Nothing on this page is intended as interpretation of any legal authority such as water rights and supply. This page is intended solely as a demonstration of techniques in flood potential monitoring. The reader assumes all risk for any damages whatsoever in connection with the access, use, quality, or performance of the supplied data just so you know.  




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Copyright 2019 Carson, Reproduction permitted with attribution.
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