Every value carries the date of the data itself (not of the download) and a link to its source. Each source has a maximum age matching how often it really updates.
Data and trust
Different data arrive at very different speeds:
Disaster alerts (GDACS): every few minutes.
Weather forecasts (Open-Meteo): several times a day.
Weekly Nino SST (NOAA CPC): once a week.
Satellite images: daily, one or more days behind.
ERA5 observed rain for Samui: about 5 days behind.
Monthly indices (ONI, RONI, SOI, MEI): once a month, and a 3-month mean is centred on a month that ended weeks ago.
So "as of 2026-07-15" on the ONI is normal (that is the centre of June-August), while "as of" two weeks ago on a weather forecast is a problem. The app compares each value with its source's maximum age and marks it stale when it is too old.