Forecasts for the next 36 hours
(chart)
(These forecasts are usually updated daily)
Weather Update – 17 December 2025 | 8 a.m.
BMCB Multimodel: ICOND2 – AROME HD – ALADIN
Precipitation – next 36 hours
Rainfall totals will remain generally limited, though with clear regional contrasts:
- North of the Scheldt: 0.5 to 9 L/m²
- Between the Scheldt and the Sambre–Meuse axis: 0 to 1 L/m²
- South of the Sambre–Meuse axis: 0 to 0.5 L/m²
Today: cloudy skies with brief brighter spells
Morning
The day begins under a cloudy to very cloudy sky, with occasional breaks developing at times.
A southerly to south-westerly breeze will be moderate, with gusts of 10 to 30 km/h, lighter over southern Belgian Luxembourg (5 to 15 km/h).
Afternoon
Cloud cover remains dominant, though some brighter intervals will emerge west of the Meuse.
The wind turns south-westerly, gusting 10 to 30 km/h.
Maximum temperatures will reach around 10°C along the coast, 8 to 11°C inland, and 6 to 7°C in the High Ardennes.
Evening
Clearer spells become more pronounced west of the Meuse, while the eastern parts of the country remain largely overcast.
The southerly wind freshens, with gusts of 20 to 40 km/h.
Night
The sky stays mostly very cloudy, though occasional breaks remain possible west of the Meuse.
The southerly wind strengthens further, peaking at 30 to 50 km/h, but remaining weaker over southern Belgian Luxembourg (20 to 30 km/h).
Minimum temperatures will hover around 7°C at the coast, 7 to 9°C inland, and 5 to 9°C south of the Sambre–Meuse axis.
Tomorrow: rain in the north, brighter spells in the south
Morning
Rain spreads across both Flanders, Antwerp and western Hainaut. Elsewhere, skies remain cloudy, with a chance of brighter spells, except in the High Ardennes.
Southerly winds will be brisk, with gusts of 30 to 50 km/h.
Afternoon
Rain continues in West Flanders, while elsewhere clearer spells broaden, particularly across Limburg, the Liège region, and south of the Sambre–Meuse axis.
Southerly winds strengthen further, with gusts of 35 to 55 km/h.
Maximum temperatures will reach 11°C along the coast, 9 to 14°C inland, and 6 to 8°C in the High Ardennes.
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National Thermal Indicator
(Chart)
MULTIMODEL BMCB
(These forecasts are generally updated daily)
Weather Update – 16 December 2025 | 11 AM
The latest trends paint a climate still hesitating between mildness and chill. Until 21 December, the national thermal index is expected to fluctuate between +6 and +2, resulting in daytime temperatures that vary according to weather phases.
During the mildest periods, the mercury may still rise to 8–14°C, evoking fleeting reminiscences of late autumn. Conversely, cooler episodes will limit highs to 4–10°C, signaling a gradual transition toward a colder season.
From 23 December onward, the thermal signal will evolve more distinctly. The national index will slowly drop below 0, fluctuating between 0 and –3 until the end of the month. Maximum temperatures will be 1–7°C on the least cold days and –1 to +5°C on the coldest days.
In this context, night and morning frosts will become increasingly frequent and widespread, gradually establishing a more decisively wintery atmosphere across the country as the end-of-year festivities approach.
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General Weather Evolution for the Next Days
Europe: Analysis & Forecast maps (6=>? days)
Weather Update – 16 December 2025 | 12 PM
A breath of mild air continues to flow over our regions, carried from the Pyrenees and the Bay of Biscay. This southern airflow will generally bring mild weather, although a few weakened disturbances may locally disrupt conditions towards the end of the week.
At the same time, an oceanic low of 976 hPa will move towards Brittany (997 hPa) over the weekend, bringing light precipitation that could reach our areas.
At the start of next week, this low will shift to the western Mediterranean basin, while a strong high-pressure system extends from Ukraine (1028 hPa) to Finland and the Baltic States (1032–1036 hPa). This movement will trigger a change in the airflow over our regions, from south/southeast to east/northeast.
The continental air advected in this flow will initially remain relatively mild over the weekend, but will gradually cool and become drier at the start of next week, heralding a more stable, wintery weather pattern across our territories.
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Forecast for the coming days
(Chart)
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)
Weather Update – 16 December 2025 | 1 PM
Summary of Late December Weather – BMCB Multimodel (ICON, AIFS, ECMWF)
The latest models depict a varied week, in which December’s mild temperatures gradually give way to colder, winter-like conditions.
Thursday, 18 December
- Precipitation: 0-10 L/m² | Min/Max: 4-10° / 8-14°
- Very mild temperatures. Some light rain showers in the west, largely dry with clear spells inland. Wind from S to SW, gusts 45-65 km/h. Rain will spread across the country during the following night.
Friday, 19 December
- Precipitation: 1-10 L/m² | Min/Max: 3-9° / 7-13°
- Still very mild. Rain mainly in the center and east, while the northwest enjoys bright spells. Nighttime fog formation likely over western and central regions.
Saturday, 20 December
- Precipitation: 0.5-8 L/m² | Min/Max: 0-6° / 4-10°
- Morning fog in the west and center. Residual showers in the Ardennes, otherwise dry under a heavily clouded sky. Local rain and fog possible overnight.
Sunday, 21 December
- Precipitation: 0-10 L/m² | Min/Max: 2-8° / 6-12°
- Mild temperatures. Very cloudy with occasional light showers and brief clear spells. Rain may persist locally overnight.
Monday, 22 December
- Precipitation: 0-1 L/m² | Min/Max: 0-6° / 2-8°
- Seasonal temperatures. Sunny weather.
Probable Trend for the Holiday Period
- Tuesday, 23 December: dry, seasonal temperatures (-1 to 5° / 1 to 7°)
- Wednesday, 24 December: very light precipitation, wet snow possible in the High Ardennes
- Thursday, 25 December: generally dry, cool temperatures (-2 to +4° / 0 to 6°)
- 26–30 December: alternating light rain or localized snow in the High Ardennes, cool temperatures, minima often below 0°, maxima between 0 and 7°
Overall, late December will feel wintery, with frequent morning frost, often cloudy skies, and occasional snowflakes in the Ardennes, a clear sign that winter is approaching.
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Forecast anomalies at 500 hPa
(mid-troposphere = 5,000–6,000 m altitude)
( charts )
Update – 17 December 2025 | 7 AM
Medium- and long-range atmospheric circulation analysis
The end of December and the first half of January are expected to remain dominated by a broad high-pressure area, extending from the Atlantic Ocean to Scandinavia.
This pattern will keep our regions under a northeasterly flow, gradually introducing cooler, more continental air.
At a later stage, indications point to an increase in low-pressure activity over the nearby Atlantic. This would allow milder maritime air to move towards the British Isles and France, suggesting a possible shift towards a more unsettled weather regime in those areas.
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METEOCONSULT
BENELUX:
Weather Outlook for 3-4 weeks
Update – 5 December 2025
🗓 Period from 19 to 28 December — Christmas Week
Recent atmospheric modelling points to a calmer, high-pressure-dominated pattern during Christmas week. Under winter anticyclones, fog and low clouds are likely to be widespread, occasionally limiting sunshine. Temperatures would gradually decrease but remain slightly above seasonal norms.
🗓 Week from 29 December to 4 January — New Year Week
The high-pressure system may shift northward, introducing a more continental and progressively colder airflow. The weather would stay calm and dry, with frequent morning fog and low clouds, but with more afternoon bright spells. Temperatures would return to near-seasonal values, especially south of the Sambre–Meuse line.
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Weather Outlook for 3 months
Update 13-12-25 – 3:00 PM
Late winter outlook 2026
January 2026: unsettled and generally mild
Temperatures
A nationwide temperature anomaly close to +1.0°C is expected. Disturbed oceanic flows will frequently bring mild conditions, punctuated by brief cold-air incursions.
The probability of temperatures near or above average is around 80%.
Precipitation
A slight rainfall surplus (+10%) is likely due to frequent Atlantic disturbances within a prevailing west to south-westerly flow.
January could therefore become the wettest month of the 2025–2026 winter.
Overall pattern
A dynamic Atlantic circulation would favour a steady succession of Atlantic weather systems.
February 2026: slightly drier, still mild
Temperatures
A temperature surplus of around +1.0°C is expected to persist. Southerly to south-easterly flows may dominate between Atlantic lows and more anticyclonic conditions over central Europe.
Overall mild conditions, with occasional colder continental spells.
Precipitation
A slight precipitation deficit (-10%) is expected as weather systems become less active under the influence of continental high pressure.
Overall pattern
An alternation between anticyclonic phases and weak disturbances arriving from the west or south.
Short cold and dry periods may occur in between.
March 2026: finally a seasonally normal month?
Temperatures
Values close to seasonal averages, alternating between colder spells and milder, more unstable periods.
Precipitation
Rainfall amounts generally close to climatological normals.
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Update to BMCB Multimodel – since 1 October 2025
from ICON (replace location left above )
from ECMWF (replace location left above)