Modèle:

FMI (Hirlam Model from finnish meteorological institute)

Mise à jour:
4 times per day, from 08:00, 14:00, 20:00, and 00:00 UTC
Greenwich Mean Time:
12:00 UTC = 13:00 CET
Résolution:
0.068025° x 0.068025°
Paramètre:
Cloud cover (low,middle,high,total)
Description:
Clouds are vertically divided into three levels: low, middle, and high. Each level is defined by the range of levels at which each type of clouds typically appears.

Level Polar Region Temperate Region Tropical Region
High Clouds 10,000-25,000 ft
(3-8 km)
16,500-40,000 ft
(5-13 km)
20,000-60,000 ft
(6-18 km)
Middle Clouds 6,500-13,000 ft
(2-4 km)
6,500-23,000 ft
(2-7 km)
6,500-25,000 ft
(2-8 km)
Low Clouds Surface-6,500 ft
(0-2 km)
Surface-6,500 ft
(0-2 km)
Surface-6,500 ft
(0-2 km)


The types of clouds are:

High clouds: Cirrus (Ci), Cirrocumulus (Cc), and Cirrostratus (Cs). They are typically thin and white in appearance, but can appear in a magnificent array of colors when the sun is low on the horizon.

Middle clouds: Altocumulus (Ac), Altostratus (As). They are composed primarily of water droplets, however, they can also be composed of ice crystals when temperatures are low enough.

Low clouds: Cumulus (Cu), Stratocumulus (Sc), Stratus (St), and Cumulonimbus (Cb) are low clouds composed of water droplets.
FMI:
FMI
At the Finnish Meteorological Institute, results from several numerical weather prediction models are utilized. Most of all, these include products from the European Centre of Medium Range Forecasts (ECMWF), located in Reading in the United Kingdom. For shorter range forecasts, more detailed forecasts are produced in-house using a limited area models (LAMs) called HIRLAM and HARMONIE, which are being developed by FMI as an international co-operation programme with a number of European countries.
NWP:
La prévision numérique du temps (PNT) est une application de la météorologie et de l'informatique. Elle repose sur le choix d'équations mathématiques offrant une proche approximation du comportement de l'atmosphère réelle. Ces équations sont ensuite résolues, à l'aide d'un ordinateur, pour obtenir une simulation accélérée des états futurs de l'atmosphère. Le logiciel mettant en œuvre cette simulation est appelé un modèle de prévision numérique du temps.


Prévision numérique du temps. (2009, décembre 12). Wikipédia, l'encyclopédie libre. Page consultée le 20:48, février 9, 2010 à partir de http://fr.wikipedia.org/w/index.php?title=Pr%C3%A9vision_num%C3%A9rique_du_temps&oldid=47652746.