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This site aims at providing output of weather prediction models of the highest possible quality.

Frequently asked questions (FAQs)

Frequently asked questions (FAQs)

What makes different from other weather sites?

Weather forecasts are generated based on so-called weather models. These are computer models that are run by national weather services and a limited number of private companies. Most weather forecast websites and apps display the output of one such weather model, which might not always be the most accurate one for a given place and time. Others let you choose among a large number of models, making it difficult for the user to pick the best one. We combine the best of both aspects, choosing the best weather model based on our knowledge among many for each place and time. At the same time, we focus on an aesthetic and simple user interface.

Which models are used by

We choose what we think is the best model for a given place and time from the following list of models:
NameResolution / kmInitialization hours (UTC)Integration time (hours)
ICON130, 6, 12, 18180 (we use 120)
ICON-EU70, 6, 12, 18120
AROME1.30, 6, 12, 1842 for 0 and 12 UTC runs, 36 otherwise
RDPS100, 6, 12, 1884
HRDPS2.50, 6, 12, 1836
HRRR-CONUS3hourly (we use it every three hours) 48 for 0, 6, 12, 18 UTC runs; 18 otherwise
We constantly look for new models to include.

How does know what the best weather model for a given place is?

We don't always know for sure. However, as a general rule of thumb, the model with the highest horizontal resolution is the most accurate model. This is because models with a smaller distance between grid points can capture more weather features. There might be cases where we deviate from this rule though.
Furthermore, models with higher resolution are usually regional models (in contrast to global models, which simulate the weather over the whole globe), that only run out for a couple of days. That is why we switch to the next-coarser model once the most accurate model's forecast span is reached.

For which regions forecasts are available on

We provide weather forecasts for the whole world.

What is the cloud cover?

The cloud cover indicates how much of the sky is covered by clouds. 0 % indicates a clear sky, whereas at 100 % cloud cover, the whole sky is covered by clouds.

What is the dewpoint?

The dewpoint is a measure for how moist the air is. It can never be larger than the temperature. If the so-called spread, which is the difference between the temperature and the dewpoint, is smaller than two degrees, fog can be expected.

How does the map work?

The map displays the forecasted precipitation amount within one hour. One of the models ICON, ICON-EU, ICON-D2 and AROME is chosen automatically, depending on the position of the map.
Radar is not yet included.

Theoretical aspects

We also work on a textbook on theoretical meteorology (in German), which you can freely download here.