I would be interested in alerts when a particular value combination arises in the forecast.

The overall alert condition is a combination of several subexpressions.

let me lay out the idea by example:

given:
location1, location2, location3, time-of-day1, time-of-day2
maxtemp

if  (temperature(location1, time-of-day1, surface) < maxtemp) AND
    (wind(location1, time-of-day1, surface, IconEU) < 10km/h) AND
    (wind(location2, time-of-day2, FL180, ECMWF) > 80 km/h) AND
    (wind_direction(location2, time-of-day2,FL180, ECMWF) between 290 and 20 degrees)) AND
    (wind(location3, time-of-day3, surface, IconEU) < 10km/h) AND
    (temperature(location2, time-of-day1, surface) < maxtemp)

then
   create alert("Alps crossing possible")

having this done once nightly looking into the future as far as models provide that would be super useful.

I admit the parameterization is complex and probably pushing the envelope for a mobile gui - it might be more productive to address the issue algorithmically (plugin idea!)

thanks for this great tool!

Assuming the average alert user is as clueless about Javascript as I am:

a framework feature for generating alarms, and a set of predefined, selectable (possibly user-contributed) JS fragments (really condition expressions) which can be parameterized:

that would go a long way without the complexity of a full-blown programming language based solution

I thought you might like this:

a local flight in Styria last month:
https://cesium.com/cesiumjs/cesium-viewer/?source=https://static.mah.priv.at/cors/stiwoll-muggauberg.czml

two balloons crossing the Alps late last year:
https://cesium.com/cesiumjs/cesium-viewer/?source=https://static.mah.priv.at/cors/filzmoos-treviso-oesoe-oesfy.czml

the trajectory lines are generated from the GPX files the windy-traj plugin offers as download, the flight tracks are actual GPS data

motivational screenshot of the latter flight:

and here is a 360° video of that flight:

note the whole animation is encapsulated in a single CZML file and just uses the public CesiumViewer service from the Cesium project

• Michael

ps: for the curious: this documents arguments to the CesiumViewer

Re: anybody working on a trajectory plugin?

is that planned to work eventually?
will it never work for some reason?

thanks! pawed through the FAQ and articles - couldnt find an answer

The most prestigious gas balloon race in the world is the annual Gordon Bennet Cup

Pilots stay aloft for several days and might cross the continent

To get an idea, here's a video of the tracks flown this year:

The teams have (and need!) a ground crew which advises pilots on weather and tactics

This year, windy and traj were part of the games - in the ground support for the Belgian, Spanish and US teams - Kolja Packard wrote up a field report (he was part of the support team and worked the weather forecasts):

(this is still german-only, I will post an english translation shortly and notify here):

https://blog.mah.priv.at/index.php/2019/10/01/erfahrungsbericht-einsatz-von-windy-beim-gordon-bennet-cup/

In particular, have a look at the very first image in the blog post - this was the track forecast 20 hours (!) before takeoff

compare that to the youtube video above - the match is amazing!

Many thanks to Kolja in writing this up!

have you considered turning off notifications for a start?

@rittels Thanks for this phenomenal job!

this is already very useful - will do a balloon ride tomorrow early morning and see how that fares relative to the plot!

If I may add a suggestion:

if you select several altitudes on the plot it is hard to discern which track belongs to which altitude

why not choose different colors for each track in the plot and color the altitudes in 'Select levels' accordingly?

• Michael

semi-related: I wrote up a tutorial on Alps crossings with a hot air balloon as there is next to zero material available on the issue

it gives an idea of the meteorological prerequisites: http://static.mah.priv.at/public/alpcrossing/assets/player/KeynoteDHTMLPlayer.html#0

(suggestions for improvement and bug reports welcome)

Here's something neat: visualize an expected balloon flight in 3D based on a windy trajectory:

https://ayvri.com/scene/49j7m8dzje/cjzp38qi200013d5vtyo4jj3j

The GPX file was created with windy.com and the traj plugin. It includes an ascent and descent phase of 2m/s and level flight at 1500m. The GPX file was then uploaded to ayvri.com (free account required).

The ayvri visualization is based on cesium.js - for the curious, play here: https://cesiumjs.org/Cesium/Apps/Sandcastle/index.html?src=CZML Path.html

Here's another long jump - from today

435km in under 4hrs, peak 80kts - and phenomenal forecast accuracy!

https://blog.mah.priv.at/gpsvisualizer/20200105044229-47167-map.html

with my hobby - hot air ballooning - it's the other way around as for the *glider folk:

mornings: we do not wait with flying until the thermals set in, we better land when they do

evenings: good to know when the thermals subside - between then and darkness we can go for a flight and sometimes it becomes too short

super useful - as is the regional indication of thermal activity

thanks @filip_k !

reported as fixed by users

back to normal

certain corporate firewalls like to strip any accept-encoding headers, killing the advantage of precompressed assets like brotli or gzip.

working on a fix

We're tracking a webserver issue with a certain german corporate environment - obviously their firewall mangles headers leading to a 404 on some data files

service will be shaky for an hour or two until the issue is nailed

• Michael

@justinlimbo start here: https://opendata.dwd.de/weather/nwp/icon-d2/grib/

@justinlimbo DWD just announced that the forecast span of ICON-D2 will be extended to 48hrs (up from 27) by June 23

I think this is significant because it extends the usability of the model to cover a weekend - e.g. check friday evening, forecast will cover all of saturday and much of sunday; before: saturday only

if you find any issues:

for the plugin please use https://github.com/rittels/windy-plugin-radiosonde/issues
if clearly in the skewt display code, please use https://github.com/rittels/skewt-js

for any backend functional issues and feature suggestions please file an issue at https://github.com/mhaberler/radiosonde-datacollector/issues and I'll look into it.

For operational issues, the DevOps Borat strategy applies:

@ivo appreciated!

@ivo if I may add a suggestion:

The recent ICON/ICON-xx come in several distribution forms, two of which are:

• standard pressure levels (1000hPa, 950/925 etc )
• "half height levels" (= 65 layers which seem to be geodaetic heights, not pressure levels)

for the vertically oriented (=aviation folk of various shapes and forms) the higher resolution would be useful - at least in the "VFR layers" (= below 5000m)

it comes at a storage + processing cost though

@ivo Superb - very good move!