What will the weather be like in the coming months in France? If it is impossible to make a forecast, let alone a reliable one, over such a period, it is possible to partially identify a trend. Météo France has published them for the months of October, November and December.
These trends are expressed as a percentage. These are therefore probabilities that a scenario will occur, but in no way a certainty. They are calculated for very large geographical areas of at least 1,000 km on each side, or a little more than the size of France. They are therefore very global and do not take into account the local weather at all. This is a sort of large-scale average. Furthermore, they are more reliable regarding temperatures than precipitation.
A scenario seems to emerge for precipitation
For example, during an overall warmer quarter, it may locally have been colder over the same period. In the same way, in a quarter predicted to be drier than normal, flooding may well occur in places, without this reversing the average result. Finally, since we are dealing with probabilities, there is always a possibility that the scenario that is most likely to occur may not occur at all.
These limits of seasonal trends having been established, it is possible to look at what Météo France anticipates, without taking it for an absolute truth. Concerning precipitation, France could be split in two, not along a North-South axis, but North-West – South-East. West of a line from the English Channel to Hérault, there is a 50% chance that the sky will be drier than usual and that there will be less rain than the seasonal norm. The chances are then shared equally, at 25%, whether it rains as much or more than the standards. In the east of the country, no scenario takes over.
For temperatures, no scenario has half the probabilities. Two of them share the same percentage of 40%: three months warmer than average and three months consistent with normal. A period colder than average has the least chance of occurring with only 20%.
In the shorter term, the month of September should end with a very slight temperature deficit across the whole of France. It would be a first for a month to be cooler than the norm since January 2022.
