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

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

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

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

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

A video from the second flight:

oh, and embeds of course

just stumbled over this - seems Austria actually pioneered the field back in 1849:

On This Day: Austria Drops Balloon Bombs on Venice

@marekd I really appreciate you're listening

come to think of it, could well be this will create kind of an aftermarket - like collections of reusable links for a certain purpose; also great to add to websites

a common question: what is the weather tomorrow/day after tomorrow/mornings/evenings in location X?

Since it's a common question, I'd create a bookmark and click the bookmark for an answer. However, windy does not allow you to do that since it uses absolute date and time:

https://www.windy.com/?2020-08-20-06,48.651,14.477,11,m:e0dagy0

so one can ask for the weather on Aug 20, 2020 mornings in Vissy Brod, but not for 'tomorrow's weather in Vissy Brod' - and link to that

proposal: enable relative time URL's in windy.

Chris' traj plugin does exactly that: it supports either absolute date/time or relative date/time like so (see the Relative day selector in the 'Create URL' submenu)

absolute time: https://www.windy.com/plugins/windy-plugin-traj?time=2020-08-20T06:00&lat=48.6128&lon=14.3222&duration=120&airspaces=&start=true

relative time: https://www.windy.com/plugins/windy-plugin-traj?time=1T06:00&lat=48.6128&lon=14.3222&duration=120&airspaces=&start=true

so time=0T18:00 means today, 18:00 UTC and 2T06:00 UTC means day after tomorrow, 6:00 UTC

The time-relative links are perfect for bookmarking - give it a try in Windy traj, bookmark some and play with them. You'll see how useful they are.

Can I ask you to look into this?

best regards

Michael

@Gkikas-LGPZ ok, I will spill the beans

found this in a US Forces surplus store:

here's some phun: trying to fly straight over a church tower: https://blog.mah.priv.at/index.php/2020/08/16/todi-precision-approaches/

the tracks window contains the forecasts by traj for the days in question - they were super on-spot!

since traj is moving ahead quickly: here's a post on how to create bookmarks/links for sharing with traj: https://blog.mah.priv.at/index.php/2020/08/15/constructing-windy-traj-links-for-sharing/

hm, link to twitter didnt work, so video here

like so, for example ;-)

@vsinceac overlooked that. Thanks!

I‘m particularly looking forward 3d wind animation