COSMO (Consortium for Small-scale Modeling)
27 times per day, from 00:00, 03:00, 06:00, 09:00, 12:00, 15:00, 18:00, 21:00 UTC
Greenwich Mean Time:
12:00 UTC = 12:00 GMT
0.0625° x 0.0625°
Precipitation in mm (or litres per square metres)
The precipitation map - updated every 6 hours - shows the modeled precipitation in mm.
The precipitation areas are encircled
by isohyets - lines with equal amounts of precipitation. However, modeling precipitation is
still not very reliable. If you compare the modeled results with observed values you will
realize that the model is nothing better than a first order approach. Yet this chart is of some
use for forecasters.
Note: Based on international convention meteorologists use the metric system. 100 mm of
precipitation is equivalent to roughly 4 inches.
The COSMO-Model is a nonhydrostatic limited-area atmospheric prediction model. It has been designed for both operational numerical weather prediction (NWP) and various scientific applications on the meso-β and meso-γ scale. The COSMO-Model is based on the primitive thermo-hydrodynamical equations describing compressible flow in a moist atmosphere. The model equations are formulated in rotated geographical coordinates and a generalized terrain following height coordinate. A variety of physical processes are taken into account by parameterization schemes.
The basic version of the COSMO-Model (formerly known as Lokal Modell (LM)) has been developed at the Deutscher Wetterdienst (DWD). The COSMO-Model and the triangular mesh global gridpoint model GME form – together with the corresponding data assimilation schemes – the NWP-system at DWD, which is run operationally since end of 1999. The subsequent developments related to the model have been organized within COSMO, the Consortium for Small-Scale Modelling. COSMO aims at the improvement, maintenance and operational application of the non-hydrostatic limited-area modelling system, which is now consequently called the COSMO-Model.
Numerical weather prediction uses current weather conditions as input into mathematical models of the atmosphere to predict the weather. Although the first efforts to accomplish this were done in the 1920s, it wasn't until the advent of the computer and computer simulation that it was feasible to do in real-time. Manipulating the huge datasets and performing the complex calculations necessary to do this on a resolution fine enough to make the results useful requires the use of some of the most powerful supercomputers in the world. A number of forecast models, both global and regional in scale, are run to help create forecasts for nations worldwide. Use of model ensemble forecasts helps to define the forecast uncertainty and extend weather forecasting farther into the future than would otherwise be possible.
Wikipedia, Numerical weather prediction, http://en.wikipedia.org/wiki/Numerical_weather_prediction
(as of Feb. 9, 2010, 20:50 UTC).