Does it always rain in Belgium? In some weeks that may seem to be the case, but in the last decade Belgium actually counted between 180 and 212 rain days a year. And in none of these years, the annual rainfall surpassed the thousand millimeters. Rainfall peaked in 2016, at roughly 940 millimeters. In 2015 however, rainfall had only been 737 millimeters – the lowest rainfall in the period considered here.

 Belgium’s maritime climate   

Belgium has a temperate maritime climate, with cool summers and moderate winters. In the 2006-2016 period, the average temperature in the country was between 9.7 and 11.9 degrees Celsius. 2014 was the warmest year in the past decade, with an average temperature of nearly 12 degrees.

The Belgian winter  

Next to a large number of rain days, Belgium’s average winter usually counts a number of frost days as well, when temperatures drop below zero. In 2010, there were nearly 75 such days. By comparison, 2014 had just ten frost days. That year, there was just one ice day, defined as a day in which the maximum temperature during the day is below the freezing point as well. In 2016, there were two ice days in Belgium.

Does it always rain in Belgium? Well, there is some truth in each stereotype! Although it certainly does not rain every day, there is a lot of rainfall in Belgium. In 2016, it rained 190 out of 366 days, or over half of the days. And this was by no means a record: in 2012, it rained 212 days, or nearly 60 percent of all days. That year, the rainfall was nearly 1,000 millimeters. In 2016, although there were fewer rain days, rainfall was still over 940 millimeters.

 Fortunately the sun sometimes shines too  

Having read this, one might be forgiven for thinking the climate in Belgium is rather bad. Fortunately, Belgians have ample time to enjoy the sun as well. In 2016 for example, there were nearly 1,600 hours of sunshine. This was significantly more than in 2007 and 2008 for instance, when there were less than 1,500 hours. In recent years, 2011 was the sunniest year, with almost 1,800 hours of sunshine.

Average temperature around 10 degrees Celsius  

All year round, the average temperature in Belgium is around 10 degrees Celsius in the last decade. In 2016, the average reached 10.7 degrees, a slight decrease compared to the two previous years, when the average temperature was 11.9 (2014) and 11.3 (2015) respectively.

Belgium Maximum 5-day Rainfall: 25-year Return Level data was reported at 7.903 mm in 2050. Belgium Maximum 5-day Rainfall: 25-year Return Level data is updated yearly, averaging 7.903 mm from Dec 2050 (Median) to 2050, with 1 observations. The data reached an all-time high of 7.903 mm in 2050 and a record low of 7.903 mm in 2050. Belgium Maximum 5-day Rainfall: 25-year Return Level data remains active status in CEIC and is reported by World Bank. The data is categorized under Global Database’s Belgium – Table BE.World Bank.WDI: Environmental: Climate Risk. A 25-year return level of the 5-day cumulative precipitation is the maximum precipitation sum over any 5-day period that can be expected once in an average 25-year period.;World Bank, Climate Change Knowledge Portal (https://climateknowledgeportal.worldbank.org);;

The climatological network contains about 200 stations spread over the whole country. It consists of voluntary observers recruited by the RMI, professional observers of Skeyes (civil aviation) or the Air Force (military aviation) and civil servants of the state, communities or private companies. The observers measure the amount of rain fallen in the last 24 hours in the pluviometer of the RMI every morning at 8 o‘clock. In more than half of the stations the extreme air temperatures are also recorded by reading the maximum and minimum temperature in a standardized weather shelter. The observers send their observations either on a daily or on a monthly basis to RMI. This product is not publicly available yet.

GTS data from Belgium for 2007,
data are extracted from the original WMO bulletins for a subset of WMO FM12 code,
data have been collected and processed at the Department of Meteorology and Geophysics,
no data quality control at the Department of Meteorology and Geophysics, University of Vienna at all,
24h-accumulation performed at the University of Hohenheim and University of Vienna,
for further details see file: jdc_data_description.pdf in entry "jdc_obsdata_info_1".

We present annual maximum precipitation data from 10-min pluviograph stations of the Royal Meteorological Institute of Belgium. This includes the 110-year time series (1898-2007) of Uccle, Brussels (Demarée, 2003), and 17 other pluviograph series, but for a much shorter period (1967-2004). Some of these series display long periods with missing data, whereas the Uccle series is complete. All the series were recorded with a Hellmann-Fuess pluviograph.

We constructed annual maximum d-hourly precipitation for rainfall durations d = 10min, 20min, 30min, 1h, 2h, 3h, 6h, 12h, 24h, 48h, and 72h. The annual maximum data was analysed in Vannitsem & Naveau (2007), Van de Vyver (2012; 2015a,b; 2018), and in Van de Vyver et al. (2021).

The files include:

• "AM.PP.BELGIUM.RData": for each of the 18 stations, the annual maximum rainfall depths (mm) are listed in a matrix (rows: year, columns: rainfall duration). The data is also accompanied by the geographic coordinates (longitude/latitude/altitude).
• "MAP.STATIONS.pdf": elevation map (m) of Belgium, together with the location of the 10-min pluviograph stations.
• "INFO.STATIONS.pdf": table with the geographic coordinates (longitude/latitude/altitude).

References

• Demarée, G. R., 2003: Le pluviographe centenaire du plateau d'Uccle: son histoire, ses données et ses applications. La Houille Blanche, 4, 1-8.
• Vannitsem, S., and P. Naveau, 2007: Spatial dependences among precipitation maxima over Belgium. Nonlin. Processes Geophys., 14 (5), 621-630, doi:10.5194/npg-14-621-2007.
• Van de Vyver, H., 2012: Spatial regression models for extreme precipitation in Belgium. Water Resour. Res., 48 (9), W09549, doi:10.1029/2011WR011707.
• Van de Vyver, H., 2015a: On the estimation of continuous 24-h precipitation maxima. Stoch. Environ. Res. Risk. Assess., 29 (3), 653-663, doi:10.1007/s00477-014-0912-5.
• Van de Vyver, H., 2015b: Bayesian estimation of rainfall intensity-duration-frequency relationships. J. Hydrol., 529 (3), 1451-1463, doi:10.1016/j.jhydrol.2015.08.036.
• Van de Vyver, H., 2018: A multiscaling-based intensity-duration-frequency model for extreme precipitation. Hydrol. Process., 32 (11), 1635-1647, doi:10.1002/hyp.11516.
• Van de Vyver, H., B. Van Schaeybroeck, R. De Troch, L. De Cruz, R. Hamdi, C. Villanueva-Birriel, P. Marbaix, J.-P. van Ypersele, H. Wouters, S. Vanden Broucke, N.P.M. van Lipzig, S. Doutreloup, C. Wyard, C. Scholzen, X. Fettweis, S. Caluwaerts and P. Termonia, 2021: Evaluation framework for sub-daily rainfall extremes simulated by regional climate models. J. Appl. Meteorol. Climatol., 60 (10), 1423-1442, doi: 10.1175/JAMC-D-21-0004.1.

This repository contains the crowdsourced data from the Leuven.cool project, a citizen science network of around 110 low-cost weather stations (Fine Offset WH2600) distributed across Leuven, Belgium. The current repository contains the raw, unprocessed measurements, as received from the sensors. Data has a 16-second resolution. The dataset contains a total of 1,019,965,287 observations, covering the period from June 2019 to March 2025.

The processed, quality-controlled and bias-corrected dataset is published in this resource: Beele, Eva; Reyniers, Maarten; Aerts, Raf; Somers, Ben, 2022, "Replication Data for: Quality control and correction method for air temperature data from a citizen science weather station network in Leuven, Belgium", https://doi.org/10.48804/SSRN3F

The following columns are available in the RAWDATA*csv files:

Data is grouped into files, each covering a three-month period (calendar quarters). It is recommended to use the timestamp of the measurement's reception by the server (DATEUTC) as the valid timestamp. Missing values are represented as NULL.

The file STATIONS.csv contains metadata about the stations, with the following columns:

。（停止更新）最大5天降雨量：25年回报水平数据按年更新，12-01-2050至12-01-2050期间平均值为7.903毫米，共1份观测结果。该数据的历史最高值出现于12-01-2050，达7.903毫米，而历史最低值则出现于12-01-2050，为7.903毫米。CEIC提供的（停止更新）最大5天降雨量：25年回报水平数据处于定期更新的状态，数据来源于World Bank，数据归类于全球数据库的比利时 – Table BE.World Bank.WDI: Environmental: Climate Risk。

In recent decades, atmospheric concentrations of greenhouse gases and aerosols have increased mainly as a result of human activities. That increase leads to increased temperatures on Earth, which entails climate disruption. This indicator assesses the extent to which changes occur in the occurrence of periods of extreme precipitation in Belgium. After all, periods of extreme precipitation can lead to flooding, while long dry periods lead to the desiccation of ecosystems and the degradation of water resources.

Standardised Precipitation-Evapotranspiration Index在2021达0.632NA，相较于2020的-1.333NA有所增长。Standardised Precipitation-Evapotranspiration Index数据按每年更新，1960至2021期间平均值为-0.102NA，共62份观测结果。该数据的历史最高值出现于1965，达2.502NA，而历史最低值则出现于1976，为-2.195NA。CEIC提供的Standardised Precipitation-Evapotranspiration Index数据处于定期更新的状态，数据来源于World Bank，数据归类于Global Database的比利时 – Table BE.World Bank.WDI: Environmental: Climate Risk。