Trying to predict the weather has progressed a bit since the days of killing a chicken and interpreting the guts, but not a lot. It turns out that there is a concept called “Persistence” which means predicting for tomorrow what is happening today. Generally, persistence is about 80% right. Beating persistence is the goal of weather forecasters everywhere. In Australia, they are on about 83% with all their satellites and technology.
In the end, we all have to interpret our own weather when deciding what to wear, when to go to the beach or whether or not to fly. One of the best things our Federal Government does with our taxes is to fund the Bureau of Meteorology. (BOM). Their website, BOM.gov.au is a mine of information and is worth rambling through.
When I am trying to assess the conditions, I first check the Mt. Stapylton radar in Brisbane. This is part of the national radar net which tracks the present situation. I have bookmarked this radar, which will give access to other radars in the vicinity as well as weather conditions at Cape Byron, Ballina and other stations when the box is checked to the right of the screen. Click on the location and voila! Winds, temperatures, dewpoints, etc. for the present and the previous 72 hours.
Next things to have a look at for future planning are the 4 day charts which show the BOM’s best guess as to what is going to happen. Sometimes they are spot on. But if the gradients are weak, they can be inaccurate. Still, it is grist for the prognostication mill.
4 Day Synoptic Forecast Charts:
When I have a visual picture of the future, I turn to the BOM version, written in plain English, unlike the aviation versions.
Northeast District Forecast:
Elders also has a good collection of charts and predictions which are easier to read in some respects and cover a full week.
Elder’s 7 Day Forecast:
Then there are the aviation forecasts. They are good, but are written in code which dates back to the old teletype days. They also use Greenwich times, which require adding 11 hours for daylight saving time. For some reason, they demand a user name and password, which they then give on the website. It is: bomw0007, aviation The Area 20 forecast gives winds aloft which is good for trip planning.
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To get forecasts for particular airports, like Ballina and Lismore go to the followiing site. The language is akin to Chinese and needs a bit of practice to decipher.
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Now, what does all this mean? Well, if the forecast is for heavy rain and thunderstorms it is pretty obvious. Stay at home. In addition to bad visibility, rain on the wings greatly affects take off performance, L/D and stall speeds. Wind is another matter. At Tyagarah, If the wind is blowing from the NE (using runway 05) or SW (using runway 23) the wind can be up to 15 knots or so before flying becomes difficult. Experienced pilots can handle higher winds.
Unfortunately, Tyagarah often has winds from other directions, notably the North and Southeast. These winds blow across the runway after striking trees and other obstructions. In addition to normal crosswind problems, there is also considerable turbulence. The worst conditions are caused by wind blowing across and around Dieter’s Hill to the South during southerly winds. There is often a zone of sink, coupled with turbulence. When using runway 23 in these conditions, it is better to do circuits on the north side of the field. The sink zone was a contributing factor in several crashes, both of which demolished the gliders.
So, when strong northerlies or southerlies are forecast, play golf. As Macca says, “If the hangar doors are rattling, don’t open them.”
In the meantime, put all these weather sites on your bookmarks and get used to interpreting them. Not only is it interesting, but it can make life more enjoyable and extend your life span.