aart wrote:
Someone alerted me to this. Apparently Skydemon uses their data in their ‘flyable conditions’ feature.
I went to their web site but I haven’t found much except METAR/TAF which can be obtained via zillion other services. And I found “actual weather” and forecasts for airports that don’t produce METAR/TAF which I confirmed to be pretty questionable (although based on only one airport and looking through the window). Maybe I’m missing something.
I chatted with them at Aero Expo. The website they showed me was AirportWeather, but their brochure mentions ‘meandair’ as being the engine behind it. Their added value over standard METARs and TAFs is apparently two fold:
(1) Interpolation to give METARs and TAFs for arbitrary locations. They don’t just interpolate existing METAR and TAF data, but also add in data from a bunch of other verified sensors. The interpolation is based on academic work (done in Belgium? perhaps. Company is based in Belgium, but I can’t remember where the original research was done.)
(2) The other sensors that they use, update much more frequently than the METAR data, so they update their pseudo METARs and TAFs more frequently (every 15 min?).
Seems quite clever to me. You leverage the big computing power of the official meteorological providers by adding in some (presumably clever) interpolation and add in more frequent updates by just having to calculate the very short term changes implied by the data changes from the real-time sources.
They also told me that they provide the raw data for Sky Demon’s flyable conditions feature, but that Sky Demon does some extra computation on it. I think the extra computation was related to the graphical presentation only.
AirportWeather looks very good. “Flyable” was one of the only reasons I was considering retaining my Skydemon subscription when it expires since GarminPilot now has all of the features I want, so being able to get this via another means is great.
Not sure how one could usefully interpolate TAFs. They are rule driven, with stuff like PROB30 TEMPO being intended to map onto AOC operating requirements (fuel reserves etc).
I think nothing beats windy.com today, for GA. Use ECMWF and it’s all there. Cloudbases, approximate tops, etc.
Peter wrote:
Not sure how one could usefully interpolate TAFs.
Even METAR can’t be easily interpolated if you have challenging terrain, even if the actual airports you use for interpolation can be fairly close. The other day when I checked AirportWeather, it gave estimate of cloud base of 4000 feet while it was actually 2000 – one nearby airport (40 NM but on the other side of the mountain) was CAVOK at that time and the other at similar distance (50 NM) was BKN010 CB TSRA. Today it’s the opposite – it gives cloud base at 0 ft, although it’s above 2000 (probably SCT-BKN) while nearby airports are CAVOK (other side of the mountain) and BKN015 (down the valley).
