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    Description of weather overlays

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    • lotayah446L Offline
      lotayah446
      last edited by

      @gjwolfswinkel said in Description of weather overlays:

      The freezing altitude layer, how does that work? I am often looking at ski weather and on those sites, the current freezing altitude (frostgrenze in German, vorstgrens in Dutch) is at around 3800 meters. Yet the 'freezing level' layer shows values of 2500 to even 1900 meters for those locations, even though the current temperatures there are much higher.
      Am I misinterpreting what the freezing altitude layer actually is or does? Or is the data faulty?

      The freezing altitude layer or the freezing level is a meteorological term that refers to the altitude in the atmosphere where the temperature is at or below freezing (0 degrees Celsius or 32 degrees Fahrenheit). The altitude at which the freezing level occurs can vary depending on the temperature profile of the atmosphere, and it can be affected by factors such as atmospheric pressure, humidity, and wind.

      In the context of skiing weather reports, the freezing level or freezing altitude is an important parameter to consider because it determines whether precipitation will fall as snow or rain at different altitudes. If the freezing level is high, then precipitation will fall as rain at lower altitudes, which can result in unfavorable ski conditions. On the other hand, if the freezing level is low, then precipitation will fall as snow at lower altitudes, which is generally more desirable for skiing.

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      • asif ali 10A Offline
        asif ali 10
        last edited by

        How does weather overlay work?

        As a weather overlay, the navigation chart, fishing chart, and perspective 3D view can all be layered on top of each other to display information related to weather and weather conditions. Depending on the chart, both the navigation chart and the fishing chart can be displayed with weather radar, cloud top heights, lightning, weather buoys, county warnings, and hurricane warnings.

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        • emilyyyZzzE Offline
          emilyyyZzz | Premium
          last edited by

          Is there any description or any more information on the Satellite overlay with BLUE, VIS, and IR lenses? Apologies if already asked.

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          • M Offline
            mrp 2
            last edited by idefix37

            Screenshot_20230524_152805.jpg

            You make it rain in my place!! And there is terrible sun and clear sun

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            • idefix37I Offline
              idefix37 Sailor Moderator @mrp 2
              last edited by idefix37

              @mrp-2

              Windy does not make rain !
              The layer that you show is the forecast of lightning per sq .km (l/km2). It just predict a possibility of thunderstorms.

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              • Gkikas LGPZG Offline
                Gkikas LGPZ Moderator Meteorologist
                last edited by

                @asifnaveed8527
                For history of numerical weather prediction
                https://en.wikipedia.org/wiki/History_of_numerical_weather_prediction

                For the future ...
                https://www.technologyreview.com/2023/07/11/1076067/weather-forecasting-is-having-an-ai-moment/

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                • Trust Haven SolutionT Offline
                  Trust Haven Solution
                  last edited by

                  Hey, I just wanted to say a big thank you! Your content has been incredibly helpful and exactly what I needed. I really appreciate the valuable information.

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                  • Handrickson JustinH Offline
                    Handrickson Justin
                    last edited by

                    Thanks for the detailed explanation of the various overlays and their sources on Windy! It's great to have a comprehensive understanding of each feature and its functionalities. Keep up the good work!

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                    • Tiago CastelaniT Offline
                      Tiago Castelani
                      last edited by

                      How get any second is used to wind gust.

                      I made this question, because if I had that define the máximum speed occoured in one edifications that has damage with the wind, I need get the wind speed to wind gust with 3-s (seconds).

                      Can explain for me?

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                      • idefix37I Offline
                        idefix37 Sailor Moderator @Tiago Castelani
                        last edited by idefix37

                        @Tiago-Castelani
                        Your question is not clear at all.
                        You’d better ask it in your native language, we will translate it.
                        Find out here how the ECMWF consider this parameter:
                        https://codes.ecmwf.int/grib/param-db/?id=228029

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                        • c4551u5C Offline
                          c4551u5 | Premium
                          last edited by c4551u5

                          I'm confused by New snow and Snow depth - it says that snow depth in 24h will increase more than the amount of new snow in the same period. How is that possible? Here are screenshots - snow depth goes from 3.9cm to 12.2cm in 24h but new snow in the same period is 4.8cm.

                          Screenshot_20231125_074423_Windy.jpg Screenshot_20231125_074433_Windy.jpg Screenshot_20231125_074446_Windy.jpg

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                          • idefix37I Offline
                            idefix37 Sailor Moderator @c4551u5
                            last edited by

                            @c4551u5
                            See information about Snow depth forecast by ECMWF:
                            https://charts.ecmwf.int/products/medium-snow-sic?base_time=202311250000&projection=opencharts_central_europe&valid_time=20231125000
                            As explained by ECMWF, below 10 cm there is some inaccuracy.
                            I agree it is weird as the density is increased after the snowfall. It should decrease.
                            It shows it is not arithmetic :)

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                            • helloworld1H Offline
                              helloworld1
                              last edited by idefix37

                              The freezing altitude layer, how does that work? I am often looking at ski weather and on those sites, the current freezing altitude (frostgrenze in German, vorstgrens in Dutch) is at around 2000 meters. Yet the 'freezing level' layer shows values of 2500 to even 1900 meters for those locations, even though the current temperatures there are much higher.

                              Am I misinterpreting what the freezing altitude layer actually is or does? Or is the data faulty?

                              Thanks!

                              idefix37I 1 Reply Last reply Reply Quote 0
                              • idefix37I Offline
                                idefix37 Sailor Moderator @helloworld1
                                last edited by idefix37

                                @helloworld1

                                Here is what the ECMWF says about this parameter:

                                “ This chart [of the freezing level] represents the height of the air temperature 0°C isotherm.
                                The chart shows the highest altitude where the temperature passes from positive to negative values with increasing height. It does not show zero degree levels in an inversion where temperatures pass from negative to positive values with increasing height.
                                The altitude of the 0°C isotherm allows some estimation of the level where snow melts to rain. It is also important in aviation, especially for smaller aircraft, as accumulation of ice on the airframe can occur at altitudes near to this level”.

                                Furthermore, this temperature is that of the air mass in free atmosphere but not at ground level. Therefore, there may be a certain deviation from the temperature observed locally, particularly in case of temperature inversion.

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                                • M Offline
                                  Mary_G
                                  last edited by

                                  Hello! I couldn’t find a description, where I can read about the Thunderstorm layer from ECMWF weather model, thanks!
                                  c846714b-6e6c-448e-be5d-d45c4867bbd5-image.png

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                                  • idefix37I Offline
                                    idefix37 Sailor Moderator @Mary_G
                                    last edited by idefix37

                                    @Mary_G
                                    You have it in your screenshot.
                                    This layer represents the forecast by the ECMWF model of the number of lightning strikes per sq.kilometer for a day.
                                    I/km2 means lightning per sq.kilometer.
                                    See more information:
                                    https://codes.ecmwf.int/grib/param-db/?id=228057

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                                    • M Offline
                                      Mary_G @idefix37
                                      last edited by Mary_G

                                      @idefix37 thank you! on my screenshot - there is description: "number in one day", it is a little bit confusing

                                      Thunderstorms - defined as number of lighting flashes in the area of one square kilometer, in one day.

                                      but it clears now, thanks - Note that this parameter has units of flashes per square kilometre per day. Conversion of this parameter to units of flashes per 100 square kilometres per hour can give values that are easier to interpret.

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                                      • 111 0001 Offline
                                        111 000
                                        last edited by

                                        Под каждым слоем как в цивилизованном мире нету краткого описания в контекстных меню?)

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                                        • F Offline
                                          faiqarani
                                          last edited by

                                          Here’s a concise, human-readable summary of the features:

                                          Radar, Lightning: Displays weather radar and real-time lightning strikes, using different data sources but sharing a timeline for animated playback.

                                          Wind: Shows average wind speed 10 meters above ground, with gusts computed for the last 3 hours and a 10-day accumulation map for maximum wind intensity.

                                          Rain, Thunder: Displays rain/snow accumulation for the last 3 hours with a lightning density forecast.

                                          Rain/Snow Accumulation: Forecasts total rain or snow accumulation over the next hours or days.

                                          Snow Depth: Predicts snow depth, influenced by various factors like terrain and urban areas.

                                          Precipitation Type: Indicates types of precipitation (rain, snow, sleet, etc.).

                                          Thunderstorms: Counts lightning flashes per square kilometer per day.

                                          Temperature: Shows temperature 2 meters above ground.

                                          Dew Point: Temperature at which air moisture forms dew.

                                          Humidity: Relative humidity 2 meters above ground.

                                          Freezing Altitude: Altitude where temperature hits 0°C.

                                          Wet Bulb Temperature: Lowest temperature via evaporative cooling, critical at 35°C.

                                          Solar Power: Amount of solar radiation reaching the Earth's surface.

                                          UV Index: Measures the sunburn-producing UV radiation strength.

                                          Clouds: Shows cloud cover at different altitudes and their rain/snow accumulation.

                                          Fog: Displays fog conditions, influenced by local factors.

                                          Visibility: Measures how far objects or light can be clearly seen.

                                          CAPE Index: Indicates potential energy for storm formation.

                                          Thermals: Shows thermal activity and cumulus cloud occurrence.

                                          Waves: Significant wave height and period, combining swell and wind waves.

                                          Sea Temperature: Estimates sea surface temperature.

                                          Currents: Displays surface sea currents.

                                          Tidal Currents: Tidal movements influenced by Earth, sun, and moon.

                                          CO Concentration: Carbon monoxide levels in the air.

                                          Dust Mass: Concentration of dust particles in the air.

                                          SO2 Mass: Sulfur dioxide concentration, often from volcanic activity or fossil fuels.

                                          Ozone Layer: Total column of ozone, affecting UV radiation.

                                          Soil Moisture: Amount of water available to plants in the soil.

                                          Moisture Anomaly: Deviation of soil moisture from average levels.

                                          Drought Intensity: Compares current soil water with historical levels for drought assessment.

                                          Pressure: Atmospheric pressure at sea level.

                                          Weather Warnings: Alerts from national weather agencies.

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                                          • pusat monitoringP Offline
                                            pusat monitoring | Premium
                                            last edited by

                                            Hi Moderator, i wanna ask you something.. can i get the raw data of precipitation prediction or nc file?

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