The Background
Throughout the centuries, fortune-tellers, soothsayers and weather forecasters of dubious credentials, have produced literature purporting to be a forecast for the season ahead, be it summer or winter. By the law of averages, some of these predictions have proved correct,  but these purveyors of uncertain truths are only famous for 15 minutes.

Source of all Rumours
The current furore about the 'cold winter to come'  appears to emanate from the British 'Met Office' and a 'News Release' on 26th September entitled 'Emergency Planners on Amber Alert'.   One must question the wisdom and sensitivity involved in such an emotive headline, especially in the context of regular terrorist alerts and the prospect of avian 'flu mutation. The tabloid newspapers, and their counterparts within the television industry, have seized upon the headline, and certain passages of text, to produce stories that could easily frighten those most vulnerable in society.

The Facts
In reality, the article produced at the  'Met Office' of the United Kingdom, found at the following address, www.met-office.gov.uk/corporate/pressoffice/2005/pr20050926.html is a fairly sober representation of an experimental forecast based on the North Atlantic Oscillation. This, in general terms, is the strength of the circulation of the atmosphere across the northern hemisphere. In 'positive' years, of which there have been many in the last 2 decades, the pressure gradient during the winter months in the Atlantic Ocean between Iceland and the Azores is strong. In other words, the difference between pressure readings in Iceland, where low pressure prevails, and those taken in The Azores,  where high pressure prevails, is greatest in years of 'Positive North Atlantic Oscillation'.  The result is a strong westerly airstream across the Atlantic with mild temperatures and copious amounts of rain affecting much of western and northern Europe; with high pressure over southern and eastern Europe producing a deficit of rainfall, as well as deficient snowfall for the Alps and Sierra Nevada. Temperatures, however, are generally above average, especially on Mediterranean coasts where radiative cooling is less marked due to the presence of the still relatively warm sea.

The Season  Ahead.......maybe
The winter of 2005/2006 is expected to have a 'Negative North Atlantic Oscillation'  resulting in less pressure gradient between Iceland and The Azores, and therefore a weaker cross-Atlantic flow. Theoretically, this should allow greater than average radiative cooling for the European land mass, especially northern Europe, where the winter sun is ineffectual.   The high pressure over Europe will act as a block, deflecting weaker than usual low pressure systems both to the north and to the south.  The  systems  heading towards the Mediterranean should produce wetter than average conditions in most southern European countries, and for many places the increase of cloud, and the temporary incursions of cold air,  as depressions move away east, should result in below average temperatures.

Possible Impact on the Weather in Malaga.
Rain in Malaga during the winter months usually arrives from 2 sources, mainly from the west or northwest on active cold fronts, sometimes preceded by high-level thunderstorms spreading north from Morocco; or by cold air above the relatively warm sea producing showers.  The former source may produce more rain than normal if depressions, and associated fronts, frequently move east from the Atlantic and cross Iberia at low latitudes. The latter  source may also produce more frequent, and heavier, showers than usual if the air in the Mediterranean basin is colder than normal.

A Wind from......
The main factor in determining whether Malaga benefits from either of the rain sources is the wind direction. The shelter from the north,  provided by the mountains, protects the Costa del Sol from much of the rain that arrives from that direction. These also act as a barrier to the low temperatures found on the plateau of interior Spain. In fact, the foehn effect of the strong northwest wind frequently raises temperatures well above the average in the winter months.  If the winter was to be cold over Europe, and the emphasis is on if, then February may be the coldest month of the 3, relative to normal,  as high pressure builds westwards from Siberia. This is hinted at by the experimental forecast for the winter months.  If that does prove to be the case, then cold air may be drawn well south over the Mediterranean and allow the centres of low pressure to be situated near the north african coast. The result would be brisk easterly winds for the Malaga area, an abundance of heavy showers, but with temperatures influenced by sea air and therefore, despite extensive cloud cover, not too low.

Summary
To summarise: the British 'Met Office' predict a 66% chance that a 'Negative North Atlantic Oscillation' will occur this winter and result in below average temperatures over much of Europe.   The impact of such an event along the Costa del Sol is uncertain,  but it would probably result in more windy conditions than normal, a small decrease in sunshine amounts, an increase in rainfall, but perhaps not until February, and temperature levels similar to those of previous years. It must be emphasised that this is not a forecast, but rather a 'what if' based on a computer-modelled hypothesis.  Real forecasts can be, and should be, accurate for 2 or 3 days ahead; fairly accurate, or a reasonable guide up to 5 days ahead , and sometimes of use in general terms up to 10 days ahead. Beyond that time, so many factors are at work in the atmosphere,  on the land and under the seas, that  accurate forecasts are impossible, and those that claim otherwise are doing the science of meteorology an injustice.