Meteorological forecast model (HIRLAM E11) — historical analysis data

DESCRIPTION The dataset contains historical analysis data from the HIRLAM forecast model. This means that only data for the first time step (the current situation description) have been selected at the respective time point. Forecast data not included. Data is available until 18 March 2014. The HIRLAM model is then replaced by the more high resolution model AROME. HIRLAM is a numerical forecasting model that describes weather trends in time and space. The model has been developed within an international cooperation involving the Nordic countries and also Ireland, the Netherlands, Spain and Lithuania. The forecast is based on what the weather looks like at a certain point in time, the so-called initial state. In order to map this, an analysis of the weather situation is carried out. In doing so, an earlier forecast is modified to better match current observations. This is done by a variety of methods. Thus, the value of the different forecast parameters can be determined in a grid. At present, these squares are 11 x 11 km to a horizontal extent and the atmosphere has been divided into 60 vertical levels. Four forecasts are made per day and each forecast extends up to 3 days in the future. Every 6 hours a day a three-dimensional mapping of different weather parameters is made. The survey is made to determine conditions in the soil, but not least to describe what it looks like in the atmosphere. It may relate to temperature, humidity, wind, air pressure, cloudiness and precipitation, but also to radiation conditions, the distribution of sea ice or the water content of snow. In short, everything that matters for the development of the weather. However, the data presented here has been limited to wind (horizontal and vertical), temperature, relative humidity and the height of various atmospheric pressure surfaces. Otherwise reference is made to data from MESAN. The analysis is carried out over an area covering Scandinavia, the British Isles, the northern part of the continent and the Baltic States. COORDINATES Coordinates of the area are given by the corners: Southwest 48.48N, 12.07 W Northwest 77.0N, 15.1 W northeast 64.56N, 55.24E southeast 42.6N, 22.7E The grid windows are 11*11 km. USE At SMHI, HIRLAM is used as a basis for forecasts in radio and television. It is also used for forecasting commercial customers such as various newspapers and municipalities. Data from HIRLAM can also be used as input to other models. This applies to both meteorological, hydrological and oceanographic. FORMAT Data is delivered in GRIB format. Information that facilitates use can be found at: https://www.smhi.se/data/oppna-data/grib-format-1.30761