Safety topic from Episode 4

Weather forecasts

All the prayers in the world are never going to guarantee VFR flying conditions. You can embrace every ounce of optimism you can muster, but it isn’t going to change the outlook of today’s weather. The only answer is to be as prepared as possible by studying how the experts have interpreted the existing and trending conditions. 

Deciphering a forecast

Deciphering aviation forecasts can be challenging, but they deliver vital information that we as pilots are obliged to obtain before our flight. Competence with reading and correctly interpreting the forecasts comes from one place: familiarity. You have to practise, and then practise some more. You need to fully understand every item on a forecast to get the full picture. If you are in doubt about any aspect of the wording, have a read through AIP Gen 3.5.3 Aviation Forecasts and get familiar with all the terms and codes. And always, if there’s something you still don’t understand, ask your instructor to help you. 

Interpreting the weather does not, however, stop there. It’s important that you form a picture of how the forecast weather is going to affect your flight. For example, if there is a front coming through, know what time it is due, what direction it’s moving and how much of your route it may affect.  (EFB apps have addressed this problem, with active links from those unfamiliar PCA locations used on the forecast to an actual line on the area of your route that the weather event is forecast to affect.)   

Translate the information you read into a practical thought process. Should you delay your departure, or plan via lower ground due to doubtful terrain clearance along your planned route? Should you cancel the flight entirely? Do you need extra fuel in case of diversion? You’re the pilot in command, remember, and therefore hold ultimate responsibility for the safe conduct of this flight.

If you are not used to flying far from your home airfield, then it’s important to understand unfamiliar information on other regions, which may never appear on your home area forecast, like widespread bushfire smoke as the Northern Territory cops routinely, or periodic locust plagues across our agricultural area. As part of your flight planning, bring up a distant area forecast and see if you can interpret what’s going on.  You need to be aware of conditions that may be very different to those you are used to flying in.  

And don’t forget those basic rules:

  • GAF (graphical area forecasts) cloud heights are AMSL (above mean sea level)
  • TAF & TTF:  cloud heights are given AGL (above ground level), ie above aerodrome elevation

And you know that land line number at the end of the Area Forecast? That’s the number of a qualified weather adviser at Airservices Australia who you may call if you wish to discuss the weather forecast and gain a clearer picture of what is expected. 

Weather Apps & websites

These days, we have excellent sources of aviation weather information including NAIPS, now available as an app for your tablet or iPad. If you have an internet connection, Airservices’ NAIPS is a well designed program from which to source aviation-specific information including your weather forecasts, last light information and restricted area briefings. However, for the purpose of operational flight decisions (pre-flight or in-flight), a CASA approved aeronautical information provider is required to be used, of which NAIPS is but one.  

For added weather awareness, why not take advantage of modern technology? As well as the excellent weather forecast access in your EFB, the Weatherzone Plus App is a really useful tool and uses Bureau of Meteorology forecasts. It’s important to note that Weatherzone does not provide aviation-specific weather, but it still proves its worth in the cockpit as an additional source of general weather conditions. There is an upgrade version, Weatherzone Pro, available for an extra couple of dollars, which includes features like lightning and wind streamlines, three-hour temperature and rain probability charts and high resolution radar images. Remember the rules, however. It is a tool that must only be used to supplement other approved sources of aeronautical information.