Glider pilots all around the world spend their days sitting in their offices at home or at work checking the weather for the coming days to see if they should drop everything, kiss the girls goodbye and head out to the airfield.
Pilots who live in Sydney, as I do, assess the soaring weather patterns from November through March constantly. It is an obsession. The question is, when should I drop everything and make the six-hour trip to Naromine? The latest four day Australian Bureau of Meterology (BOM) chart tells a story that every glider pilot is waiting to hear.
'My beloved wife, mother, son or daughter, it breaks my heart to go, but I'll see you in a week or two.'
INLAND TROUGH
The latest BOM four Day Chart shows a large high pressure airmass off the coast of Western Australia and another high centered off the coast of Eastern Australia. There is a developing tropical cyclone, Jasper, in the Coral Sea off the coast of northeastern tropical Queensland. However, the chart below shows no low pressure area off the coast of northern Western Australia that when it occurs, we call the Pilbara Low.
This is significant, because when moist air from the Pilbara Low is feeding into the trough depicted between the two high pressure systems, it can result in too much moisture in the trough, resulting in rain and washed out soaring conditions.
It is the inland trough that produces the classic soaring conditions in Eastern Australia - that is, the pressure difference between the two high pressure systems, east and west. When the setup of the high pressures is just right, the low pressure line, or trough, between the two will have unstable air with high convection up to and above 13,000ft. It the air is too humid, then showers, often severe, will result. If the moisture is very low, then blue convection will occur. If the cooking pot is just right, there will be cumulus and the 'classic Narromine days' that we all wait for.
Looking at this four day chart, I would be on my way to Narromine this evening, forgoing all home comforts to be ready to fly tomorrow, which is Race Day 5 at WGC Narromine.
Hold onto your hats for four exciting racing days, with maybe more to follow.
Oh, a note about Cyclone Jasper. Cylones (hurricanes, typhoons) behave unpredictably. But acordong to the BOM chart, this 'friendly ghost' will not, as feared, feed a wet tropical stream of air into our classic Narromine setup - at least for the next few days.
Sean Young
