Yr.No API has two different precip fields for each single hour: precip for this single hour or for the next 6 hours starting with this one (in API it's .next_1_hours.details.precipitation_amount and .next_6_hours.details.precipitation_amount).
Precip in KWGT was very wrong for me, so I compared data from Kustom with actual API response and precisely number by number function wf(rain, 0, h) is showing precip for 6 hours instead of for 1 hour, which is just the data from the wrong fields in JSON