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General Weather Evolution for the Next Days over the Ocean and Europe
Europe: Analysis & Forecast maps
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Synoptic evolution over Europe and the Atlantic Ocean
Update: 21 September 2026
A 1032 hPa high-pressure system, currently centred over south-western England, will move towards our region tomorrow, Tuesday. It will bring generally calm and mild conditions, although night-time and early-morning fog is likely to develop in places.
On Wednesday, a small low-pressure system is expected to form over Norway. Its associated cold front will cross the Benelux during the following night, bringing some rain as it passes.
This disturbance will then give way to a new 1025 hPa high-pressure centre over our area. On Friday, the high will shift towards the eastern Alps, allowing warmer air from eastern France to spread into our region.
Another frontal system will reach us at the beginning of the weekend, but in a very weakened form, owing to the presence of a 1022 hPa high-pressure core over the English Channel.
On Sunday, this high-pressure centre is forecast to move towards the Carpathians, where it should reach around 1025 hPa. Situated on its western flank, we will then once again be affected by a surge of warm air from southern France, extending the prevailing spell of calm and mild weather.
Probable weather evolution over Europe Likely trend (based on mid-tropospheric anomaly patterns)
https://www.bmcb.be/trend-europe-europa/
Synoptic Trend from 29 September to 5 October 2026
Data updated on 20 September 2026
At the beginning of the period, a broad area of high pressure is expected to extend from the western Mediterranean deep into Russia. This pressure pattern would favour the advection towards Belgium of continental air that is warm for the time of year, originating in particular from southern France and northern Italy.
As the period progresses, however, this air mass could gradually become somewhat more unstable and unsettled, while temperatures edge lower. Nevertheless, conditions would remain generally mild for the time of year as October begins.
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National Thermal Indicator
MULTIMODEL BMCB
(These forecasts are generally updated daily)
Temperature trend — Update of 21 September 2026
Belgium’s national thermal index is expected to fluctuate between 0 and +1 until 24 September, corresponding to seasonally normal daytime temperatures generally ranging from 16 to 23 °C. A more noticeable drop is expected on 24 September, when maximum temperatures will fall to 14–20 °C across the country.
The nights will remain cool, with minimum temperatures of –1 to 7 °C in the Ardennes, compared with 7 to 13 °C across the lowlands and along the coast.
From 27 September, the thermal index will rise markedly, reaching values between +3 and +6. This should broadly correspond to maximum temperatures of 21–27 °C.
A gradual decline is then expected, bringing daytime temperatures back towards 17–24 °C across the country during the weekend of 3–4 October.
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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 21 September 2026
A late taste of summer at the gateway to October
Following a few often misty mornings, Belgium is heading into a largely dry, calm and bright spell of weather. Until Thursday, sunshine will alternate with occasional cloud, while temperatures remain close to seasonal levels at first. From Friday onwards, the mildness will become much more pronounced, with a particularly pleasant weekend and notably warm conditions on Sunday.
This gentle weather pattern is likely to continue into early October. A few isolated showers or light spells of rain may develop around Wednesday 30 September and Thursday 1 October, but the overall trend remains one of very mild, at times unusually warm weather for the time of year. For now, autumn seems content to wait in the wings.
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)