DISCLAIMER This software is provided 'as is,' without support, and the National Weather Service (NWS) can not be resposible for any adverse effects caused by the use of this software outside the NWS.
The following evaporation information used by WSFO Topeka for the state of Kansas utilized an Evaporation Program developed by the NWS office in Sioux Falls, South Dakota (FSD) which is available for FTP below. Other information was obtained from NOAA Technical Memorandum NWS CR-56 "The Prediction of Daily Drying Rates" and from the CRH Agricultural ROML.
The monthly average radition values used in the AG program as applied to Kansas ---
Jan - 270 May - 730 Sep - 540 Feb - 380 Jun - 760 Oct - 415 Mar - 515 Jul - 725 Nov - 305 Apr - 645 Aug - 645 Dec - 250
To calculate S in the HILL EQUATION,
S = I * Pwhere
I = the monthly average radiation
P = the percent of sunshine expected for the day
The Evaporation Program was written in the Quick BASIC programming language.
Click Here to Download the Evaporation Program.