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    GFS temperature VS Weatheronline

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    • Z
      zhaoy | Premium
      last edited by

      The rendering effect of Weatheronline(https://www.weatheronline.co.uk/cgi-bin/expertcharts?LANG=en&MENU=0000000000&CONT=asie&MODELL=gfs25&MODELLTYP=1&BASE=202410101200&VAR=tmp2&HH=12&ZOOM=1&ARCHIV=0&RES=0&WMO=&PERIOD=) has many details, while Windy rendering is very smooth. Has Windy's data been smoothed

      cc33292e-82b3-4636-a5be-2fcbd2a01e6f-image.png
      2b53a60d-aa73-4944-ab90-164a3208f0a2-image.png

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

        @zhaoy
        You can change the color scale yourself for most of layers in Windy.
        See this article
        The color scale in Windy is smoothed but the way how the colors are staggered in your example gives more contrast between the temperature steps.
        And as explained in the article you can design a non-smoothed color scale.

        Z 1 Reply Last reply Reply Quote 0
        • Z
          zhaoy @idefix37 | Premium
          last edited by

          @idefix37 still smooth,There are many small patches on Weatheronlie and connected areas on Windy
          ca47fba5-5ba4-4e81-b5bc-ad8a392f4534-image.png

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

            @zhaoy
            Did you read the article I mentioned here above ? At the end I show how to make a non-smoothed color scale if you prefer it.

            Z 1 Reply Last reply Reply Quote 0
            • Z
              zhaoy @idefix37 | Premium
              last edited by

              @idefix37 There are 38 color classifications in the temperature legend of Weatheronline,I have modified the color according to legend on Windy, but there are still differences between the two images. So I guess Windy's data may have been processed.
              069b8a07-1e3f-48e1-aa41-984294bc58d4-image.png

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

                @zhaoy
                Could you show your code.

                Z 1 Reply Last reply Reply Quote 0
                • Z
                  zhaoy @idefix37 | Premium
                  last edited by zhaoy

                  @idefix37 I picked up steps with numerical values on color legend, and other steps were interpolated by numerical values
                  [[245,[136,136,136,255]],[246.5,[176,176,176,255]],[248,[204,204,204,255]],[249.5,[228,228,228,255]],[251,[119,51,119,255]],[253.4,[170,51,170,255]],[255.8,[204,51,204,255]],[258.2,[255,51,255,255]],[260.6,[255,153,255,255]],[263,[21,0,204,255]],[265,[51,102,255,255]],[267,[51,153,255,255]],[269,[51,204,255,255]],[271,[51,255,255,255]],[273,[0,119,0,255]],[275.4,[0,153,0,255]],[277.8,[0,187,0,255]],[280.2,[0,221,0,255]],[282.6,[0,255,0,255]],[285,[255,255,51,255]],[286.75,[255,238,51,255]],[288.5,[255,221,51,255]],[290.25,[255,204,51,255]],[292,[255,187,51,255]],[293.75,[255,170,0,255]],[295.5,[255,153,0,255]],[297.25,[255,119,0,255]],[299,[255,0,0,255]],[301,[238,0,0,255]],[303,[204,0,0,255]],[305,[187,0,0,255]],[307,[170,0,0,255]],[309,[153,0,0,255]],[311,[136,0,0,255]],[313.5,[114,0,0,255]],[316,[91,0,0,255]],[318.5,[66,0,0,255]],[321,[29,0,0,255]]]

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

                    @zhaoy
                    Thank you.
                    Could you try

                    [[245,[136,136,136,255]],[247.9,[176,176,176,255]],[248,[204,204,204,255]],[250.9,[228,228,228,255]], [251,[119,51,119,255]], …etc

                    It should improve the scale, but not sure you get exactly what you want.

                    Z 1 Reply Last reply Reply Quote 0
                    • Z
                      zhaoy @idefix37 | Premium
                      last edited by

                      @idefix37 thank you! the result is not yet which I wanted,I think the same data source (GFS 0.25°) should render the same results,but the Weatheronline image has many small patches,and the boundary is quite sharp.
                      WeatherOnline Result:
                      b72829d3-5ee7-4021-9530-460ec2eabf15-image.png

                      so,I guess Windy did some smoothing on the data, I don't know if it's appropriate.
                      such as this picture
                      4ee3e094-1cd8-46ce-9f5d-f21d881d3be8-image.png

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

                        @zhaoy
                        You are being picky. I find the granularity to be pretty good.
                        At boundary between the value ranges the limit is jagged. Can you try taking a screenshot of the Icing layer of the same device.
                        Then could you explain the 2 squares with numbers. How did you make them ?

                        Z 1 Reply Last reply Reply Quote 0
                        • Z
                          zhaoy | Premium
                          last edited by zhaoy

                          The temperature data(GFS 0.5°) render result on meteoblue,which also has many small patches,and the boundary is quite
                          https://www.meteoblue.com/en/weather/maps/#coords=5.65/37.766/99.822&map=temperature~hourly~GFS05~2 m above gnd~none

                          81ea7421-afcc-4397-b2d3-90c1d660f96a-image.png

                          1 Reply Last reply Reply Quote 0
                          • Z
                            zhaoy @idefix37 | Premium
                            last edited by

                            @idefix37 I'm just guessing if Windy smoothed the source data to make it look better

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

                              @zhaoy
                              I didn't realize you didn't apply the correct coding.

                              0309D9EB-32EC-4880-A2C3-C31569678643.jpeg

                              As already said, your coding should be like this theoretical diagram

                              97BA89E3-6C5F-4AD8-8D53-12FE10EC7482.jpeg

                              Z 1 Reply Last reply Reply Quote 0
                              • Z
                                zhaoy @idefix37 | Premium
                                last edited by

                                @idefix37 I guess it's not a color rendering issue, Did Windy lose a lot of details in smoothing the source data(GFS 0.25°)

                                [[245,[136,136,136,255]],[246.4,[136,136,136,255]],[246.5,[176,176,176,255]],[247.9,[176,176,176,255]],[248,[204,204,204,255]],[249.4,[204,204,204,255]],[249.5,[228,228,228,255]],[250.9,[228,228,228,255]],[251,[119,51,119,255]],[253.3,[119,51,119,255]],[253.4,[170,51,170,255]],[255.7,[170,51,170,255]],[255.8,[204,51,204,255]],[258.1,[204,51,204,255]],[258.2,[255,51,255,255]],[260.5,[255,51,255,255]],[260.6,[255,153,255,255]],[262.9,[255,153,255,255]],[263,[21,0,204,255]],[264.9,[21,0,204,255]],[265,[51,102,255,255]],[266.9,[51,102,255,255]],[267,[51,153,255,255]],[268.9,[51,153,255,255]],[269,[51,204,255,255]],[270.9,[51,204,255,255]],[271,[51,255,255,255]],[272.9,[51,255,255,255]],[273,[0,119,0,255]],[275.3,[0,119,0,255]],[275.4,[0,153,0,255]],[277.7,[0,153,0,255]],[277.8,[0,187,0,255]],[280.1,[0,187,0,255]],[280.2,[0,221,0,255]],[282.5,[0,221,0,255]],[282.6,[0,255,0,255]],[284.9,[0,255,0,255]],[285,[255,255,51,255]],[286.65,[255,255,51,255]],[286.75,[255,238,51,255]],[288.4,[255,238,51,255]],[288.5,[255,221,51,255]],[290.15,[255,221,51,255]],[290.25,[255,204,51,255]],[291.9,[255,204,51,255]],[292,[255,187,51,255]],[293.65,[255,187,51,255]],[293.75,[255,170,0,255]],[295.4,[255,170,0,255]],[295.5,[255,153,0,255]],[297.15,[255,153,0,255]],[297.25,[255,119,0,255]],[298.9,[255,119,0,255]],[299,[255,0,0,255]],[300.9,[255,0,0,255]],[301,[238,0,0,255]],[302.9,[238,0,0,255]],[303,[204,0,0,255]],[304.9,[204,0,0,255]],[305,[187,0,0,255]],[306.9,[187,0,0,255]],[307,[170,0,0,255]],[308.9,[170,0,0,255]],[309,[153,0,0,255]],[310.9,[153,0,0,255]],[311,[136,0,0,255]],[313.4,[136,0,0,255]],[313.5,[114,0,0,255]],[315.9,[114,0,0,255]],[316,[91,0,0,255]],[318.4,[91,0,0,255]],[318.5,[66,0,0,255]],[320.9,[66,0,0,255]],[321,[29,0,0,255]]]

                                Windy (GFS 0.25°):
                                cd7deff2-9664-424a-acd1-9caa5ff2d2fc-image.png

                                Meteoblue (GFS 0.5°):
                                9f875cfe-b173-4213-b8df-f234db48a6e6-image.png

                                WeatherOnline (GFS 0.25°):
                                1bf39bd8-cb58-47dd-b151-abbd5c25f554-image.png

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

                                  @zhaoy
                                  You already posted the same screenshots.
                                  You can guess what you want.
                                  End

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