Home' Afloat : AFLOAT August 2015 Contents Take monthly with water August 2015 67
*Mal Riley is the Media and Communications Manager for the Bureau
of Meteorology in Hobart. He has worked in meteorology for 40 years.
He is a skipper of the tall ship The Lady Nelson and a keen sea kayaker.
• Hardstand with 50t lift
• On-site engineer
• Premium unleaded, diesel
and pre-mix fuel available
7 days a week
Servicing all your boating needs in one convenient
location, Burraneer Bay Marina provides premium
quality facilities and excellent customer service
• Fully private marina with
• Private secure carpark for
• Shop with snacks, ice
creams, bait and ice
BERTHS • MOORINGS • BROKERAGE • SLIPWAY • MARINE ENGINEER
48 Fernleigh Rd, Caringbah NSW 2229 | T: 02 9523 5250
34.25” x 29.5” x 6.5”
Max Power Output
1,000 W (2,000 W Peak)
100/240 V, 50/60 Hz
For more information visit:
Revolutionizing how hundreds of millions of people access power, the FORTY2
combines solar technology, advanced electronics, and easy to use design.
Not a Kit
No need to buy separate Parts
Rated for 1,000 full charge and discharge cycles
No noise, smell, or fuel cost
1/20th the cost of a gas generator
Low Cost of Ownership
Open Up, Plug In,
coming soon to Australia
Clean, renewable back-up power for boating/camping/medical devices/
disaster relief & recovery and off-grid operations
Storage Capacity 250 wHr to 2,000 wHr
Coca Cola Place, Level 17, 40 Mount Street, North Sydney, NSW Australia 2060
Cell: 0432 534 310 Office: 61-2-8415-9841
For more information please visit: www.peppermintenergy.com
The air picks up speed and keeps accelerating down the
lee side of the Alps. In severe Boras the wind gusts can reach
250km/h – similar to speed gusts experienced in a Category 4
Above is a graphical forecast predicting a Bora. The speeds
are metres per second (roughly double for knots). You can see
as the wind flows over Croatia and Bosnia it is a benign north-
easterly of about 10 knots. However once it tops the Alps it picks
up speed so as just out from the coast (the white dashed line)
speeds are forecast between 50 and 60 knots. The winds then
remain gale force for most of the Adriatic Sea across to Italy.
To see how extreme a Bora can be, view this video www.
youtube.com /watch?v = BnGMCGIHVFU
Katabatic winds can vary greatly in strength from a few knots
up to 100 knots.
One of the instances of 100 knot katabatic wind occurs
occasionally at Australia’s Casey base in Antarctica; and probably
at many other Antarctic locations. Very cold dense air forms on
top of the (around) 3,000 metre Antarctic Plateau.
The air begins to sink towards the coast increasing in speed
as it is funnelled by the valleys. Being a plateau the height falls
very quickly near the coast. Gravity then further increases the
speed of the wind from around 10 knots on the plateau to strong
gale force around 40 to 50 knots, occasionally reaching 100 knots
at Casey station which is located on the coast.
It does help the increase in wind speed that there are very
few things (like trees) to cause friction slowing down the wind.
Most river valleys around the world produce katabatic winds.
All of the New South Wales river valleys east of the Dividing
Range would produce katabatic winds to some degree. Some on
their day would move fog down the valleys towards the mouth
of the river. Mostly these winds would be between five and 15
knots and not really a problem for most boats. However, smaller
watercraft such as kayaks and small yacht tenders may struggle
in the conditions.
• The Bureau of Meteorology will be at the Sydney International
Boat Show (SIBS), located in the Marine Safety Precinct. Visit the
stand to learn more about the five vital weather safety checks
and tools to help you plan your journey around the weather. h
Graphical forecast predicting a Bora.
Links Archive AFLOAT July 2015 AFLOAT September 2015 Navigation Previous Page Next Page