I notice that the temperature value in the first 3 hour forecast is not constant over that period. For example, if I call the api at 12:05 then the 12:00-15:00 forecast may show 12C but if I call request the forecast again 40 minutes later then then value may be 14C. And again if I call request 60 mins later it may be up to 16C. The current time is still between 12:00-15:00 so I would have expected the value to be constant.
It is almost like the first period is not a forecast over the full three hours but rather a forecast from the time of the api call until the end of that period. Could that be the case?
Current forecast period may be corrected using current temperatures, that’s why it can change.