Third release candidate for v2026.10.1. Bug fixes only, both found by @Megalos comparing the hourly calculation with Open-Meteo on a real installation. If you are on rc1 or rc2, update.
Fixes
- A night without rain can no longer give water back to the bucket. rc1 summed the hours of a window with their sign. A calm humid night prices a hair below zero for each hour (about -0.015 mm, for some fourteen hours a day in October), and once the day's sunny hours were in the window, each of those hours lowered the running total: the live bucket climbed back by a few hundredths of a millimetre every evening. An hour that evaporates nothing is worth zero again, as in beta 4 and as FAO-56's worked example prints it. A test now states the rule: the total of a growing window never falls. (#866)
- Evapotranspiration is back to where the hourly equation puts it. The same signed sum took about a tenth off the day on humid autumn days, which is where the 16% gap with Open-Meteo reported in #879 mostly came from. Fed with Open-Meteo's own hourly inputs, the equation now follows their values hour by hour. If you were on rc1 or rc2 and are on the hourly calculation, your zones will water a little more than they did on those two.
- Open-Meteo's hourly sun is no longer an hour late. Open-Meteo stamps its radiation with the end of the hour it averages, and we read it as the hour starting at the stamp. This only affected installations with no radiation sensor, using Open-Meteo's own sun history or forecast for the hourly equation. (#879)
What is not in this release
A few percent of difference with Open-Meteo remains on days like the one in #879. It comes from how the hours are rebuilt from readings taken every hour or so, where Open-Meteo's figures are means over the whole hour. The proper fix, pricing the hourly equation from Open-Meteo's own hourly history for sensor groups it feeds, is a new way of collecting the data and not a correction, so it is planned for the stable after v2026.10.1.
Everything in rc1 and rc2 applies, except rc1's signed sum of the night hours, which this release takes back.
Trying it
Enable beta versions for Smart Irrigation in HACS, update, restart, and reload the browser. 1822 backend tests. 🙂