Description:

The equivalent potential temperature map - updated every 6 hours - shows the modelled equivalent potential temperature at the 850hPa level. The equivalent potential temperature is commonly referred to as Theta-e (θe). θe is the temperature of a parcel of air after it was lifted until it became saturated with water vapour (adibatically). When this parcel becomes saturated and condensation begins, the process of condensation releases latent heat into the surrounding air. This latent heat further warms the air making the air even more buoyant. We refer to this as a moist adiabatic or saturated adiabatic process. Moist adiabatic expansion increases the instability of the parcel. If this process of moist adiabatic expansion continues, all of the water may condense out of the rising parcel and precipitate out, yielding a dry parcel, and is dropped adiabatically to an atmospheric pressure of 1000 hPa. The potential temperature of that new dry parcel is called the equivalent potential temperature (θe) of the original moist parcel
In meteorology θe is used to indicate areas with unstable and thus positively buoyant air. The θe of an air parcel increases with increasing temperature and increasing dewpoint as for the latter more latent heat that can be released. Therefore, in a region with adequate instability, areas of relatively high θe (called θe ridges) are often the burst points for thermodynamically induced thunderstorms and MCS's. θe ridges can often be found in those areas experiencing the greatest warm air advection and moisture advection. (source: the weather prediction Keep in mind that if a strong cap is in place, convective storms will not occur even if θe is high.
As different origins of airmasses largely determine their own θe, one can use this parameter as a marker. Fronts are easily seen as steep gradients in θe. The boundary layer θe shows where fronts are located near the surface, while 700 hPa θe shows where they are near the 3000 m level. In winter it occurs often that warm fronts do not penetrate into the heavy, cold airmass near the surface.

CFS:

The CFS model is different to any other operational weather forecasting model you will see on Weatheronline.
Developed at the Environmental Modelling Center at NCEP (National Centers for Environment Prediction) in the USA, the CFS became operational in August 2004.
The systems works by taking reanalysis data (NCEP Reanalysis 2) and ocean conditions from GODAS (Global Ocean data Assimilation). Both of these data sets are for the previous day, and so you should be aware that before initialisation the data is already one day old.
Four runs of the model are then made, each with slightly differing starting conditions, and from these a prediction is made.
Caution should be employed when using the forecasts made by the CFS. However, it is useful when monitored daily in assessing forecasts for the coming months, the confidence levels in these forecasts and in an assessment of how such long range models perform.
A description of the CFS is given in the following manuscript.
S. Saha, S. Nadiga, C. Thiaw, J. Wang, W. Wang, Q. Zhang, H. M. van den Dool, H.-L. Pan, S. Moorthi, D. Behringer, D. Stokes, M. Pena, S. Lord, G. White, W. Ebisuzaki, P. Peng, P. Xie , 2006 : The NCEP Climate Forecast System. Journal of Climate, Vol. 19, No. 15, pages 3483.3517.
http://cfs.ncep.noaa.gov/

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.

CFS: The NCEP Climate Forecast System (CFS)