When planning a flight, I obtain the spot winds from the Met Office using chart F214. This chart gives forecast spot winds at various heights for 19 different parts of the UK.
All my flights so far have been relatively local, so each leg of my PLOG uses the same forecast wind direction/speed (from the same box in the chart).
When I plan the same route using SkyDemon, the PLOG it generates has different wind direction and speed for each leg. I’m wondering where SkyDemon gets this data from – is it published somewhere, or does it calculate it somehow?
I haven’t yet noticed a significant difference between the headings/times in my manually generated PLOG versus SkyDemon’s PLOG with its more specific winds, but I am intrigued to understand where that data comes from.
Anyone?
Why don’t you ask SkyDemon’s developers?
Without looking in detail I can assume that SkyDemon may get its forecasts via a worldwide model such as GFS (actually nearly everyone covering the whole globe does sth like that), while Met Office may have its dedicated models covering UK.
Yes I am sure that they get it from GFS, because that’s the only free weather model around, and it is machine-readable.
The UK Met office model is for paying customers only and is quite expensive. It has been claimed to be more accurate than GFS for the UK and its dominant SW airflow, but I have never known anybody who was in a position to do a comparison.
Practically all of the free weather websites that “we” use get their stuff from GFS, with some including the few free bits and pieces from say the UK MO, like the MSLP charts.
Thanks guys. I hadn’t heard of GFS, so that’s good to know. Which website(s) would you suggest using for obtaining GFS data for flight planning purposes?
