Three hour figures do not match hourly figures

[Andy_F]

Rainfall 3hr totals area same as hourly figures on Wednesday and Thursday. Hourly totals over three hours are therefore around three times that shown as three hour totals. Which is correct? If the hourly figures are correct I need to set up my flood boards.

[idefix37]

@Andy_F

When comparing 3-hour to 1-hour rain amount figures, keep in mind that these forecast panels only show rain amounts equal to or greater than 0.1 mm.
This can therefore lead to seemingly inconsistent amounts as explained here:
https://community.windy.com/topic/12851/rain-forecasts-issue?_=1711884397761

[Andy_F]

@idefix37
For example, on Thursday the 1 hour figures are
2am - 2.3mm
3am - 4mm
4am - 6mm
5am - 6mm
6am - 7mm
7am - 8mm
8am - 5mm
9am - 2.8mm
10am - 0.4mm

The three hour totals are
4am - 6mm
7am - 8mm
10am - 0.4mm

The three hour totals we can cope with, but the one hour totals would require setting up floodboards as the catchment cannot cope with that amount of rainfall over that period on already saturated ground. So it would be nice to know which values are correct.

[idefix37]

@Andy_F

In fact the 1-hour precipitations stand for the last 3 hours, as shown by the weather picker and said in the FAQ.
https://community.windy.com/topic/3361/description-of-weather-overlays?sort=oldest_to_newest
You can check it hour by hour on the Rain layer. So if you accumulate all precipitation in the 1-hour table you get an excessive total. I must admit it is confusing.
I think the accumulation of 3-hour rain is more correct.

@Suty
Please could you confirm my guess.