Light airs thwart record Atlantic attempts and keep Quebec to St Malo fleet on edge.

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Leading trimarans in the Quebec to St Malo race lie like painted ships upon a painted sea in the days after the July 30 start. Blame a broad trough of low pressure and blocked weather systems to the east for creating this tricky situation.

Image © pipoff.com - Ch. Guigueno

Light airs all around

From Hawaii to the Gulf of St Lawrence, light airs
are making yacht racing a difficult game

August 2, 2000

The pictures coming from some of the best yacht racing venues on the planet look like they were shot at the same location: In a studio under glass.

Synoptic situation across the Atlantic for August 2, 00GMT. The low pressure cell to the east of Nova Scotia has remained stationary for the last three days thanks to a stagnant weather situation. Blame that kink in the jet stream, or the big high west of Portugal, or the warm front over the US eastern seaboard, the result is the same - no wind over vast areas of New England and the Canadian Maritimes.

Image courtesy of Intellicast.

Where's the wind?

In Hawaii, the start of the Kenwood Cup was delayed - not because of storm winds from Daniel, but because of the storm's blocking effect on already weak trade winds.

The New York to Lizard trans-Atlantic record attempt by Playstation and Club Med has yet to take place because a dominant weather system in the Atlantic doesn't exist. Club Med, in fact, has given up the record attempt for now and would be half-way to Europe if not for a string of false starts.

Meanwhile, in the Gulf of St Laurence, the world's fastest 60 foot trimarans and monohulls were dead in the water until very recently, as the Quebec, Canada to St Malo France trans-Atlantic race fell victim to high summer and a stagnant trough of low pressure.

This image for August 2, 1800GMT, shows the jet stream over the north Atlantic. A convoluted mess is what is clearly seen. The stream is split over eastern Canada with one arm traveling over Greenland. The other arm flows south of Newfoundland before curving to the north over mid-ocean. This is a classic blocking situation, and together the two arms of the jet stream are helping to trap weather systems beneath them for days at a time.

Image courtesy of the Aviation Weather Center.

Is this so unusual?

Put it this way: These things happen.

Tropical storms in the Central Pacific have deadened the usual trade winds before. During the last Kenwood Cup two years ago an almost identical situation developed with the remnants of tropical storm Estell and racing was cancelled for the first time since the series started 10 years earlier.

In the Atlantic, the synoptic situation is a little more complex, with a stalled weather pattern keeping things tight for much of the past week.

A low pressure cell east of Nova Scotia has been stationary for more than three days, blocked by a high pressure cell west of Portugal and locked in place by a kink in the jet stream above.

Further to the west a fat trough of low pressure - a warm front - dominates the eastern seaboard of North America, bringing sultry conditions and renewed meaning to the phrase 'hot August night'.

For skippers in the Quebec to St Malo race, this trough helped to create windless conditions on the St Laurence River, reknowned at the best of times for flucky winds.

Now that leading trimerans are east of the trough line and heading out into the Atlantic south of Newfoundland, winds have increased from the north enough to fly one hull.

They're off at last!

This infra-red satellite image for August 2, 0700GMT, shows clearly the broad trough, or warm front, stuck over New England and the Canadian Maritimes. Underneath this broad band of loosely defined cloud are light winds. To the east of the warm front are northerly winds. Leading trimerans in the Quebec to St Malo race are now between Newfoundland and Cape Breton.

Image courtesy Canadian Department of Environment

Comparison of trimarans versus monohulls in
very light airs (from Quebec to St Malo race)

60' Multihulls Ranking at 09:52:00 UT on 01/08/00

1. Groupama - 2566.6 NM to go – Average Spd = 4.75 Knots
2. Biscuits La Trinitaine - 2568.0 NM to go – Average Spd = 5.83 Knots
3. Bayer en France - 2573.1 NM to go – Average Spd = 8.54 Knots
4. Belgacom - 2576.5 NM to go – Average Spd = 10.27 Knots
5. Foncia - 2630.5 NM to go – Average Spd = 7.83 Knots

Monohulls Ranking at 09:52:00 UT on 01/08/00

1. Geb - 2640.8 NM to go – Average Spd = 3.97 Knots
2. Artemis - 2643.6 NM to go – Average Spd = 3.39 Knots
3. Fila - 2651.6 NM to go – Average Spd = 3.06 Knots
4. Multicap Caraibe - 2654.9 NM to go – Average Spd = 3.44 Knots
5. Nastro Azzurro - 2655.4 NM to go – Average Spd = 3.06 Knots

Note: all boats are separated by just 90 miles, and have basically the same weather (Belgacom and Bayer En France have a bit more air) yet the trimarans glide almost twice as fast - this is particularly clear when you compare Foncia and Geb, separated by just 10 miles. With little wetted surface, light displacement and big rigs, these extreme trimarans are a craft of the future. No doubt they would move quicker than Club Medor Playstation in these conditions because they don't have a big second hull dragging in the water.