EPSGRAMS

Pôvodné meteogramy: A-LAEF, ALADIN, ECMWF, EPSGRAM

The epsgram displays an automatically generated forecast meteorological parameters, from the A-LAEF ensemble system. It is generated with a time step of one hour and is updated twice a day. The solid line represents the median of the forecast parameter. 50% of the scenarios lay between the lower and upper quartiles (25th and 75th percentiles), which represent forecast uncertainty, displayed as the area of the chart filled with darker colour. Edges of the area filled with lighter colour denote the maximum and minimum values of the ensemble. These represent the least likely, although still possible extremes.

The epsgram originating from the A-LAEF system is combined with the meteogram from the deterministic ALADIN/SHMU model, displayed as a dashed line in magenta. The ensemble median and the value forecast by the deterministic ALADIN/SHMU model are displayed above the top right corner of each chart, when the cursor is hovered above the charts at positions representing each hour.

Each epsgram is generated for a point defined by geographic coordinates. The forecast values are representative of a surrounding area of about 5 ⨯ 5 km and elevation as per model topography, which may not correspond with the location's actual elevation.

The EPSGRAM displays an automatically generated forecast meteorological parameters, from the ECMWF ensemble system. It is generated with a time step of three hours (for the first days) or of six hours (days 7-10)  and is updated twice a day. The solid line represents the median of the forecast parameter. 50% of the scenarios lay between the lower and upper quartiles (25th and 75th percentiles), which represent forecast uncertainty, displayed as the area of the chart filled with darker colour. Edges of the area filled with lighter colour denote the maximum and minimum values of the ensemble. These represent the least likely, although still possible extremes.

The ensemble median, minimum and maximum for every 3 or 6 hours are displayed above the top right corner of each chart, when the cursor is hovered above the charts. 

Each epsgram is generated for a point defined by geographic coordinates. The forecast values are representative of a surrounding area of about 9 ⨯ 9 km and elevation as per model topography, which may not correspond with the location's actual elevation.

• The grey background in the charts represents the time between sunset and sunrise for the chosen locality.
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• You can change the temporal resolution of the charts (zoom) by clicking and dragging over the charts.
• Air temperature is forecast at 2 m above surface, reduced to the actual elevation of the selected location. The min. and max. values displayed within the charts correspond to the minimum and maximum of the ensemble median during each day. Note that these are not the minimum and maximum of the entire ensemble and thus do not represent the largest possible forecast spread on that day.
• Cloud cover is displayed as total, and separately for low, medium and high levels. Total cloud cover is not the sum of cloud covers in the three separate layers, as cloud cover diagnostics make use of random layer overlap. Total cloud cover may reach 100 % even if the separate layers do not.
• The precipitation chart displays precipitation – a sum of rainfall and snowfall. The snowfall chart displays solid precipitation (snowfall) only. Within the chart are also displayed precipitation totals for the ensemble median during each day, and also 24-hour precipitation totals for the lower and upper quartiles of the ensemble (25th and 75th percentile).
• The mean sea level pressure chart displays surface pressure reduced to sea level. A minimum and maximum of the ensemble median are displayed within the chart.
• Wind speed at 10 m above model surface is displayed in brown, while maximum gust speed is displayed in green. The chart also contains maximum and minimum of the ensemble median wind speed during each day.
• Wind direction is shown as the likelihood of occurrence of each of the 8 wind directions. The darker the colour in the chart, the higher is the likelihood of wind from that particular direction. Below the chart, wind direction and speed from the deterministic ALADIN/SHMU model is displayed as wind barbs.

• The grey background in the charts represents the time between sunset and sunrise for the chosen locality.
• 
• You can change the temporal resolution of the charts (zoom) by clicking and dragging over the charts.
• Air temperature is forecast at 2 m above surface, reduced to the actual elevation of the selected location. The min. and max. values displayed within the charts correspond to the minimum and maximum of the ensemble median during each day. Note that these are not the minimum and maximum of the entire ensemble and thus do not represent the largest possible forecast spread on that day.
• ​​​​Cloud cover is displayed as total, and separately for low, medium and high levels. Total cloud cover is not the sum of cloud covers in the three separate layers, as cloud cover diagnostics make use of random layer overlap. Total cloud cover may reach 100 % even if the separate layers do not.
• The precipitation chart displays precipitation – a sum of rainfall and snowfall. The snowfall chart displays solid precipitation (snowfall) only. Within the chart are also displayed precipitation totals for the ensemble median during each day, and also 24-hour precipitation totals for the lower and upper quartiles of the ensemble (25th and 75th percentile).
• The mean sea level pressure chart displays surface pressure reduced to sea level. A minimum and maximum of the ensemble median are displayed within the chart.
• Wind speed at 10 m above model surface is displayed in brown, while maximum gust speed is displayed in green. The chart also contains maximum and minimum of the ensemble median wind speed during each day.
• Wind direction is shown as the likelihood of occurrence of each of the 8 wind directions. The darker the colour in the chart, the higher is the likelihood of wind from that particular direction.