I, like so many other pilots, am fascinated by the weather. And it’s a good thing too, because knowing what the weather is doing before you takeoff is paramount to safe flying. The trouble is finding accurate forecasts.
While writing this, I was sitting, looking out at a gloomy, rainy day in Johannesburg, wondering where the rain was coming from. Was it the upper reaches of a midlatitude cyclone, one of the last arms of a cold front stretching out across South Africa before the low pressure winter weather system slinks further south to hide away from the southern African summer? Or was it the return of the low pressure trough that settles over the southern African interior for summer, bringing moisture down from Angola and the ITCZ? To find out, I consulted some of my ‘go to’ weather websites, and some others that I had heard about but not looked at very closely yet.
For pre-flight planning, there’s no real substitute for phoning the Met office or consulting the South African Weather Service at aviation.weathersa.co.za for the latest METARs, TAFs and weather charts. But the Service’s aviation site isn’t open to everyone – it’s reserved for professional pilots, and those who have managed to convince the Service that they are worthy of the information – and a call to the MET office doesn’t give a visual representation of the bigger picture. My new favourite site is Windy.com. Here you can find almost everything you need as a general aviation pilot. It may just be the ultimate weather gadget.
The landing page for Windy shows the outline of southern Africa, and overlaid are moving particles showing airflow and a colour-coded background representing wind speed. It’s great at showing how weather is moving around the continent. You can zoom in and out depending on how much detail you want. But that’s just the start. A key down the right-hand side of the page presents options to display temperature, pressure, cloud cover, rain, and a number of other layers. These are shown in relation to a colour-coded key, or you can click on a point on the map to show specific weather readings. You can also specify the Flight Level you want displayed.
And, just for pilots, you can overlay airports. The number of airports shown depends on how much you zoom in. Hover over the airports and the METAR pops up; click on them and a column opens on the left-hand side of the page that shows METARs and TAFs – both in ‘raw’ mode, or decoded in to standard English. You can even display NOTAMs and airport info.
The features are too numerous to mention here.
And in case you are wondering about Jo’burg’s weather, it was a finger of a cold front moving across the country that caused the rain, as the cold front met the warm, moist air coming in from the Indian Ocean.