A climate normal is an average over a 30-years period. The period 1981-2010 is the current reference period recommended by the World Meteorological Organization (WMO). Recent climate normals are available for any locations in Belgium and several parameters including air temperature, precipitations and solar radiation. Climate normals for the reference period 1981-2010 are available for air temperature, precipitation and derived parameters (e.g., annual number of summer days, annual number of precipitation days, etc.). For solar radiation, the reference period had to be adjusted to 1984-2013 because of data availability. These climate normals are available as maps and as table for each Belgian municipality.

The data consists in tables of estimated extreme precipitation quantities for precipitation durations ranging from 10 minutes to 30 days and return periods ranging from 2 to 200 years for each Belgian municipality.

Gridded observational data provides an estimate of the spatial distribution of a meteorological variable based on observations. While instrumental measurements are taken at irregularly distributed stations, gridded data represents the meteorological variable on a predefined regular grid. Gridded observational data is of strong benefit in disciplines applying distributed quantitative models to examine the influence of weather and climate. Gridded data are also very convenient to provide estimations for any specific location of interest for the user. Gridded observational data covering Belgium at a spatial resolution of 5 km (= 1360 pixels) are available for several variables (precipitations, air temperature, sunshine duration, solar radiation, relative humidity and wind speed) as well as different temporal resolutions (daily, monthly, seasonal, annual values as well as long-term climate averages). The gridded database starts in 1961 for most variables and is updated each day with the available observations of the previous day. All grids are then updated for archiving as soon as the data quality control is completed. In addition to the 5km x 5km grids, spatial averages for all each Belgian municipality are also available. This product is not publically available yet.

UV Index derived from spectral measurements with a Brewer UV spectrophotometer. This product is not publically available yet.

Since August 2019, users of the RMI smartphone app are able to send an observation of the meteorological conditions at a certain place and a certain time. The observations provide information about the weather conditions and potentially severe weather to the other users and to RMI. The collection of citizen weather reports is a valuable complement to the information obtained with the classical instruments like stations, radar and satellite. The data can be exploited for nowcasting, warnings and model verification, and eventually in assimilation. A general introduction of the data and their characteristics can be found in Reyniers et al. (2023). A basic quality control is implemented on the received observations via a plausibility check. This plausibility check determines whether an observation is plausible, suspicious or false, by comparing it to the INCA-BE nowcasting system using a simple thresholding scheme. INCA-BE is RMI's operational nowcasting system described in Reyniers et al. (2021). There is no strict spatial extent since there is no restriction at the input side: users can send observations from all over the globe. The bulk of the observations are received from within Belgium. Note that the plausibility check is not available for reports from outside Belgium.

RMI operates a network of 17 automatic weather stations in Belgium. These weather stations report meteorological paramaters such as air pressure, temperature, relative humidity, precipitation (quantity,duration), wind (speed, gust, direction), sunshine duration, shortwave solar radiation and infrared radiation every 10 minutes.

Hail products are derived from the observed vertical profiles of radar reflectivity and the NWP vertical profiles of temperature. Three types of products are generated. poh : probability of hail of any size (larger than 0.5 cm diameter)expressed in %. posh : probability of severe hail(larger than 2cm)expressed in %. mesh : maximum expected size of hailexpressed in mm of hailstone diameter. All products are generated every 5 minutes. This product is not publically available yet.

Weather Model 'Alaro' A numerical forecast model is a computer program that simulates the evolution of the atmosphere. Available parameters : Temperature, Max. temperature, Min. temperature, Dewpoint temperature, Wet-bulb potential temperature, Cloud cover (low, medium, high, tot.), U and V wind component, U, V and vertical velocity, Stationary boundary layer (SBL) Gust, Total precipitation, Large scale rain, Convective rain, Large scale snow, Convective snow, Relative Humidity, Specific humidity, Geopotential, Mean sea level pressure, Orography, freezing level / 0°C isotherm, Convective available potential energy (CAPE)

Daily forecasts for each belgian commune, from current day up to the next 7 days. This product is not publically available.

Hail products are derived from the observed vertical profiles of radar reflectivity and the NWP vertical profiles of temperature. Three types of products are generated. poh : probability of hail of any size (larger than 0.5 cm diameter)expressed in %. posh : probability of severe hail(larger than 2cm)expressed in %. mesh : maximum expected size of hailexpressed in mm of hailstone diameter. All products are generated every 5 minutes. This product is not publically available yet.