I've been writing a lot of JavaScript code recently, and I thought I'd make a JavaScript version of my old Java wind plotting program. The first version I wrote looked pretty much like the old Java version with two separate graphs (one for wind speed and one for wind direction). Here's what that looks like in my (unfinished) JavaScript version:
- Dockweiler_WindPlot_2023-01-18_06-22-52.png (69.35 KiB) Viewed 854 times
It's not too bad, and with a little annotation it could certainly be useful. But it's probably harder to read than the Weather.gov version here (you might want to click on the photo to make sure your browser shows the whole thing):
- Dockweiler_Forecast_2023-01-18_06-19-51.png (68.29 KiB) Viewed 854 times
So I decided to "think out of the box" a little bit. I wanted something that would show the wind direction and speed as if you could
see the wind coming at you while standing on launch. That's when I came up with the idea to show the wind direction along the horizontal axis as if you could point at it. I decided to show the strength (speed) of the wind as the diameter and to show the evolution over time as if it were scrolling up (reading down the page). Here's what I ended up coding (again, you might want to click on it to show the whole thing):
- Dockweiler_BlobPlot_2023-01-18_06-22-52.png (70.5 KiB) Viewed 854 times
In this example, you can see that there are a lot of large red blobs on the right. Those are the north winds that tend to be dominating this week. But you can also see some reasonably nice green blobs right in the center on the 19th and 20th. It's hard to miss them in this format.
I'm currently calling this a "Blob Plot" because the strength of the wind is shown in the size of the blobs. Each dated rectangle represents one day (with 00:01 at the top of the box and 23:59 at the bottom of the box). I plan to add some time marks along the left edge to give it more accuracy, and I may eliminate most or all of the night time because we can't fly then anyway (this may be an option).
One of the nice features of this format is that the blobs show the progression of the wind as if you were standing on launch looking out. The best direction would obviously be right in the center, and that's why blobs near the center are colored green (for "GO"). As the wind direction moves off to either side (at about 45 degrees), the color changes to yellow as a warning for significant cross winds. And as the direction goes even further away from center, the color changes to red to represent unflyable conditions. This version currently wraps around 360 degrees so an east wind would be coming from the extreme right and/or left edges of the plot. I may add options to only show the onshore portion of this plot as well as a smooth transition of colors from green to yellow to red.
If you look at each of the 7 daily forecasts, you'll see a bit of the typical wind pattern that starts from the south and progresses to the right as the day goes on (often ending the day with a north wind). So when planning to fly, you basically look for days with big green blobs that stay right in the middle of the screen for most of the day. You can see them at a glance in this format, and it doesn't require any remembering of which direction the arrows point on the weather chart.
Making the plot isn't as easy as I would like, but it's not too hard either. I have the code set up to read the Weather.gov XML format. They have been using that same format for quite some time, so I hope it's stable by now.
If you look at the bottom of the blob plot image (you may have to click or double click to show it all), you'll see a text box with a bunch of XML in it. That XML comes from the
"weather.gov" web site. That link is currently set up for Dockweiler beach, but you can move it to other sites through their interface. You'll see an "XML" button in the upper right corner. If you click that, you'll get a page of text that looks like this (you may need to open it as source):
- Dockweiler_XML_2023-01-18_06-21-29.png (166.76 KiB) Viewed 853 times
All that text describes the weather for the week (wind, temperature, precipitation, ...). You just select all of that text and copy and paste it into the box at the bottom of the "Blob Plot" page. Then click the "Update" button and you will see the "Blob Plot" representation of that XML data. There's also a small text box beside the "Update" button where you can enter the direction that your local hill faces. For Dockweiler that's about 260 or 270 degrees, and that's the current default value. All that really does is determine which angle is centered on the screen. If you change it, all the "blobs" will just move to the right or left. This allows the same program to work on sites that don't face west.
I just finished coding this last night (and this morning), so I haven't posted it anywhere yet. Please contact me (phone, email, PM) if you'd like to try it out. Eventually I'll post it to USHawks site to make it as handy as possible. I would really like to eliminate all the cutting and pasting, but I haven't figured out how to get around JavaScript's "same-origin" policy. Ideally, you could just select a flying site from a list and the program would go to weather.gov to get the data without any cutting or pasting. But since weather.gov is a different web site, JavaScript won't allow that (at least not easily). One way around that would be to set up a server that acts as the "middle man" to get the data. Servers don't have the "same-origin" limitation, but it would take some work that I don't have time to do.
Update: The program described here has been updated and published at:
https://ushawks.org/forum/viewtopic.php?f=2&t=4212&p=34192#p34192
Posted: Mon Nov 27, 2017 11:33 am
