The picker only shows cities that are enabled in the weather city list. After you choose at least two cities, the tool fetches today plus the next seven days for each city and lines them up by relative day, so each column keeps its own local date.
Weather data is requested through the same-origin backend proxy and comes from Open-Meteo daily records. The table shows temperature, precipitation, wind, WMO weather code labels, and Actual or Forecast badges; one city can fail without hiding the others, and forecasts remain reference data.
Common questions and answers about this topic.
Between 2 and 4 cities. Add them from the picker or tap a popular-city chip; remove any with the × on its chip. The selected cities are saved in the URL so you can bookmark or share the comparison.
Each day is tagged either Actual (already-recorded weather) or Forecast (an upcoming prediction). Forecasts are inherently uncertain and may change. Today may be either, depending on the data sync.
Each city is shown in its own local date and time zone, so "today" may land on a different calendar day across cities. The rows align by relative day (today, +1, +2 …) rather than by exact calendar date.
From Open-Meteo, synced daily. Temperatures, precipitation and wind are daily summaries; the icon and text come from the WMO weather code. Forecasts are for reference only.