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Theoretical background on pwsFWI: Difference between revisions
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<math>P_{Sat}\ {{=}}\ {A} \times {e}^{\frac{{B}\times{T}} {({C}\ +\ {T})} }</math>
Where A = 6.112, B= 17.62 and C= 243.12 are the coefficients of the August-Roche-Magnus equation as found in the Guide to Meteorological Instruments and Methods <ref>[https://www.wmo.int/pages/prog/www/IMOP/CIMO-Guide.html Guide to Meteorological Instruments and Methods of Observation (WMO-No. 8, CIMO Guide)], In Chapter 4. Measurement Of Humidity, Annex 4.B. Formulae For The Computation Of Measures Of Humidity.</ref>
With this estimator for P<sub>Sat</sub> we can work straight on to an FWI for personal weather stations (which from here on I will call pwsFWI or rough pwsFWI).
<math>{pwsFWI}\ {{=}}\ {VPD} \times {Windspeed}</math>
The VPD must be seen as the largest driving factor in evaporation and as such in the drying of the fuel(s). For the Meteorological variables in the calculation per day, the daily high or total (T, Wind, Rain) or daily low (RH) values are taken.
== Some reasoning ==
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