Times Series from the ECMWF
Greenwich Mean Time:
12:00 UTC = 13:00 BST
Sea Level Pressure in hPa
The surface chart (also known as surface synoptic chart) presents the distribution of
the atmospheric pressure observed at any given station on the earth's surface
reduced to sea level.
You can read the positions of the controlling weather features (highs, lows, ridges or
troughs) from the distribution of the isobars (lines of equal sea level pressure).
The isobars define the pressure field. The pressure field is the dominating player in
the weather system.
Additionally, this map helps you to identify synoptic-scale waves and gives you a first
estimate on meso-scale fronts.
Introduction to seasonal forecasting:
The production of seasonal forecasts, also known as seasonal climate forecasts, has undergone a huge transformation in the last few decades: from a purely academic and research exercise in the early '90s to the current situation where several meteorological forecast services, throughout the world, conduct routine operational seasonal forecasting activities. Such activities are devoted to providing estimates of statistics of weather on monthly and seasonal time scales, which places them somewhere between conventional weather forecasts and climate predictions.
In that sense, even though seasonal forecasts share some methods and tools with weather forecasting, they are part of a different paradigm which requires treating them in a different way. Instead of trying to answer to the question "how is the weather going to look like on a particular location in an specific day?", seasonal forecasts will tell us how likely it is that the coming season will be wetter, drier, warmer or colder than 'usual' for that time of year. This kind of long term predictions are feasible due to the behaviour of some of the Earth system components which evolve more slowly than the atmosphere (e.g. the ocean, the cryosphere) and in a predictable fashion, so their influence on the atmosphere can add a noticeable signal.