The weather lovers' thread, volume III

The AEMET climate atlas for the 1991-2020 period brings together annual averages of rainfall, temperature and solar radiation across Spain, along with a joint atlas covering Spain and Portugal. For daily tracking, there are rain and lightning radars, satellites and wind maps open to the public.

Meteorology is part data science and part constant observation. The Spanish 1991-2020 climate atlas, produced by **AEMET**, sets the reference averages: rainfall, temperature and solar radiation for each area. It is the basis for knowing whether a year is wet or dry, cold or warm, beyond anyone's personal impression.

## The climate atlas as a reference
The **1991-2020** period is the standard used by weather services to calculate temperature and rainfall averages. In Spain, **AEMET** publishes this atlas alongside a joint Iberian climate atlas with Portugal, allowing both territories to be compared using the same data series. Without that common reference, talk of a "normal" July or a "mild" winter hangs in the air.

Annual averages of rainy days in Europe, and the averages of thunderstorm or snow days, are calculated over long series. These figures change little from one year to the next, but they help explain why some regions concentrate storms while others barely see snow.

## Radars and satellites for day-to-day tracking
For immediate tracking, rain and lightning radars show in real time where rain is falling or where electrical discharges are occurring. The **Meteosat** satellite provides cloud images over Spain and Europe, and wind direction and estimulante ilegal maps complete the picture. These are open tools, at no cost to the user.

**AEMET**'s general forecast maps cover Spain, while the European ones extend the scale. With all this, anyone can check the forecast without relying on a single source.

## What doesn't change with the volume
Popular meteorology is living through an age of maps and links, but the substance remains the same: data with a date, a unit and a territory. An average of thunderstorm or snow days only means something if you say which period and which station it refers to. The **1991-2020** atlas is, for now, the most solid reference for doing so.