Every weather station reporting on Earth, with the observed air temperature at each one. These are measurements, not a forecast.
Each square is a single weather station, coloured by the air temperature it last reported. It is not an average of an area and not a model: tapping one gives the station’s name, the figure, and the minute it was measured.
Airport reports and national weather service reports, published by NOAA. Airport stations send roughly hourly; many national ones send every six hours, which is why a station can be on the map with a reading some hours old. The station’s own page always carries the observation time.
Because there are no thermometers out there. The network is airports and national services, so it follows where people are: thick over Europe and North America, thin over the Sahara, the Amazon and the Southern Ocean. The empty water is an honest gap, not a rendering fault.
This map shows air temperature only. Satellite ground temperature and sea surface temperature are held separately and can differ from the air above them by more than 20 °C, so they are never mixed into a square here.
The globe is drawn from our own coastline data, which is honest to a point and no further. Past that zoom the view hands over to a street map, so a close look at a station is drawn at a resolution that can support it.
Readings are collected every 15 minutes and the day’s board is settled in UTC. A station that has gone quiet keeps its place in the register and loses its colour rather than being given a guess.
It is a temperature map, which is a narrower thing. It shows what the air temperature IS at each station, measured, with the time it was measured. It carries no forecast, no rain, no wind and no cloud, and it never says what tomorrow will do.
Yes. /map?lat=35.69&lon=139.69 opens on Tokyo, and adding &zoom=3 opens closer. Those views are left out of search results on purpose, since there are endlessly many of them, but they share and bookmark normally.
Either it has not reported inside the window the map is drawing, or it is one of the stations in the register whose position we do not trust enough to plot. Both leave the square out rather than placing it approximately.
The map plots instruments, not settlements. A city appears when a station inside it reports; otherwise the nearest reporting station is usually the airport, and that is the figure its page uses, with the distance stated.
Every weather station reporting on Earth, 9,168 of them at this moment. The hottest is Omidieh/Aghajan Arpt at 113.0°F and the coldest Davis Lgb 46 Aws at −88.8°F. These are observed air temperatures. Nothing here is a forecast.
10,146 stations reporting in the last 24 hours of 11,064 this pipeline can place, newest reading 12:15 UTC.
267 of them are drawn in this first picture, one per grid cell, until the full field loads. Every station held has a stored position.
Coastline: Natural Earth 1:110m, public domain. Islands smaller than about 61 km across are not drawn, so a station can sit in what looks like open water. The station position is measured; the coastline is reference geometry and is not a temperature.
Place names: Natural Earth 1:50m, public domain. These are reference labels for orientation. A landmark carries no temperature: only the station marks do.
Place names and populations from GeoNames, CC BY 4.0. GeoNames provides the data as is, with no representation of accuracy, timeliness or completeness.
32 more are marked on the map. Open any square for its reading.