SPECIAL WARNING
General Weather Evolution for the Next Days over the Ocean and Europe
Europe: Analysis & Forecast maps
LIVE IMAGERY — CLOUDS • PRECIPITATION • TEMPERATURE • WIND
Synoptic evolution over Europe — 16 September 2026
The cooler airflow moving across our regions this Wednesday remains temporarily unstable. Conditions should stabilise on Thursday, however, before a moderately active cold front crosses the Benelux on Thursday evening.
Behind this front, a fairly mild and generally stable west to south-westerly flow will become established. Within this flow, a weak disturbance will cross the Benelux on Saturday, without significantly altering the broader weather pattern.
On Sunday, an anticyclonic centre of around 1030 hPa will develop to the west of Brittany. It will strengthen slightly to 1031–1032 hPa at the beginning of next week, while shifting towards England and the North Sea.
This evolution will gradually shape the weather across our regions. Initially, the high-pressure system will direct relatively mild air from the west to north-west. The flow will then veer towards the north and north-east, before turning easterly around the middle of next week as the anticyclonic centre moves over north-western Germany.
Thus, after a succession of weak disturbances, the atmospheric circulation appears set to evolve towards a more stable pattern, with a marked change in the direction of the incoming air masses over the coming days.
Probable weather evolution over Europe Likely trend (based on mid-tropospheric anomaly patterns)
https://www.bmcb.be/trend-europe-europa/
Synoptic Outlook from 23 to 29 September 2026
Data updated on 15 September 2026
From 23 to 29 September, our regions, like much of Western Europe, are expected to remain under the persistent influence of a broad area of high pressure, generally centred between southern Britain and the Benelux countries.
This weather pattern will favour very stable air masses, with temperatures remaining fairly mild and at times even distinctly warm for the time of year across our regions.
Yet this apparent atmospheric tranquillity will have its downside. Winds are likely to remain light, limiting the renewal of the air and encouraging the development of mist and fog during the night and morning. Fog should therefore be frequent, particularly across the lowlands and valleys, before gradually lifting as sunshine becomes stronger.
Overall, the period should be characterised by calm conditions, often bright and sunny once the morning mist has cleared, and by an unusually high degree of atmospheric stability for the end of September.
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National Thermal Indicator
MULTIMODEL BMCB
(These forecasts are generally updated daily)
Temperature evolution — Update of 16 September 2026
Following the decline observed today, the Belgian national thermal index will gradually return towards neutral territory on Thursday. This will bring temperatures back close to the seasonal average, with maximum values generally ranging between 15 and 20 °C.
Thereafter, the index is expected to rise slightly and fluctuate between +1 and +3 through the end of the month. This should result initially in daytime temperatures, around 3 p.m., of approximately 16 to 22 °C.
A further rise then appears likely around 22-23 September, with temperatures potentially reaching 19 to 26 °C more widely. The second half of September should therefore remain generally mild, despite sometimes noticeable day-to-day fluctuations.
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Forecast for the coming days
Multimodel BMCB ( OPERATIONAL + ENSEMBLES ICON-GFS-ECMWF-AIFS-GCGFS )
Forecast of the range of temperatures, precipitations + general type of weather in Belgium
(These forecasts are usually updated daily)
Belgium — Weather Evolution
Update of 16 September 2026
According to the BMCB Multimodel — ICON, AIFS and ECMWF
Belgium: a very mild end to September in sight
After several unsettled days with occasional rain, conditions should gradually become more stable from the beginning of next week. Brighter spells will become more frequent, rainfall will become increasingly scarce and temperatures will rise again.
From 24 to 29 September, the BMCB models indicate a generally dry and very mild period, although a few spells of rain may still occur towards the end of the period. Fog may develop locally during calmer nights.
The end of September could therefore bring a particularly mild spell of weather, despite some unsettled conditions over the coming days.
SOURCE: METEOCONSULT
BENELUX:
Weather Outlook for 3-4 weeks
Weather Outlook – Update of 11 September 2026
28 September to 4 October: a dry week
Across northern Europe, the prevailing pattern could remain dominated by stable high pressure. This would favour settled and dry conditions in our region, with cool, occasionally misty mornings followed by pleasantly mild and bright afternoons.
5 to 11 October: little change in sight
At this stage, the signal remains remarkably consistent. Our region is likely to remain under the influence of strong high pressure firmly established over northern Europe. As a result, settled and dry autumn weather appears the most likely scenario, with some morning fog and a succession of fine days.
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Weather Outlook for 3 months
El Niño: what effects will it have on Europe?
Update of September 14, 2026
El Niño is expected to continue influencing the global climate background through autumn and into the beginning of winter. Its impact on Europe, however, remains largely indirect and highly variable. El Niño alone therefore cannot determine what kind of weather we will experience across our regions.
The key factor will be the evolution of the atmospheric circulation over the North Atlantic, together with the position and development of the main pressure systems — anticyclones and depressions — that govern Europe’s weather.
October — persistently mild and relatively dry
Mild conditions should remain dominant, with temperatures potentially around 1 °C above the seasonal average.
The return of more frequent Atlantic disturbances could still be delayed. Anticyclonic conditions may therefore remain important, favouring settled, often dry and at times very mild weather.
October could consequently remain drier than normal, prolonging the effects of the rainfall deficit inherited from the summer.
November — more Atlantic disturbances, but still mild
A change in the weather pattern could then develop, with a more clearly oceanic circulation becoming established. Atlantic disturbances would become more frequent, bringing rainfall totals back towards normal, or perhaps slightly above normal levels.
Such a development would be favourable for the gradual recharge of soil moisture and water reserves.
The mild conditions would nevertheless persist, with temperatures potentially remaining around 1 °C above normal.
December — a very mild and wet start to winter
At this stage, there is no convincing signal pointing towards a cold start to winter. On the contrary, the trend suggests continued mild conditions, with temperatures remaining around 1 °C above seasonal normals.
Brief cold outbreaks would of course remain possible, but they could be short-lived and insufficient to produce a lasting change in the overall weather regime.
Rainfall is expected to be near normal to slightly above normal, within a circulation pattern that could remain relatively oceanic.
In summary
At the present range of the forecast, the most likely scenario for our regions would therefore be a generally mild autumn: still rather dry in October, increasingly unsettled and wetter in November, followed by a mild and relatively wet start to winter in December.
Nevertheless, caution remains essential at this timescale. In Europe, the influence of El Niño is never mechanical. A change in atmospheric circulation over the North Atlantic can radically alter the character of the season within only a few weeks.
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from ICON (replace location left above )
from ECMWF (replace location left above)