Singapore weather

Two different kinds of number sit on this page and it is worth keeping them apart. An observation is a measurement that has already happened: the air temperature, humidity, wind speed and rainfall are readings taken across a station network and published with the minute they were taken. A forecast is a statement about what has not happened yet, and it carries a validity window rather than a timestamp.

The island high is the warmest station currently reporting, not an average. How many stations that is varies: the feed returns whichever were reporting when the page loaded, which is sometimes a dozen and sometimes one, and the count is shown. When several report during a shower over one part of the island the spread between them can be a few degrees, so a single islandwide temperature would be a fiction — which is why the low is shown beside it and the station is named. Humidity and wind are means across the reporting stations, and those are labelled as means.

One value on the panel is neither an observation nor a forecast. Feels like is the heat index published by the United States National Weather Service, applied to the measured temperature and humidity by this page. It is a formula with a stated valid range, it is labelled as computed, and below the bottom of its range the panel shows the measured temperature instead of extrapolating a number the formula was never meant to produce.