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Weymouth Weather Brief: 6th August 2012

Gillean Keith

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Headlines for Monday

• Gradient Wind WSW (260) 15-20 KT

• Surface winds SW (230-260) 12 G 15 KT increasing to 15 G 20 KT

• Variability in SW direction starting 250, backing 20 degrees to 230 by 1400 L then veering again around 1500 L.

• Sea State smooth (0.4-0.5 M on west course)

• Sunny day

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Synoptic Situation

Analysis Monday 0100 L Forecast Monday 1300 L

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Current Weather Situation

RADAR & visual satellite picture 0700 L

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Model products Winds forecast loop (knots)

1000 Monday

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Model products Winds forecast loop (knots)

1030 Monday

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Model products Winds forecast loop (knots)

1100 Monday

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Model products Winds forecast loop (knots)

1130 Monday

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Model products Winds forecast loop (knots)

1200 Monday

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Model products Winds forecast loop (knots)

1230 Monday

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Model products Winds forecast loop (knots)

1300 Monday

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Model products Winds forecast loop (knots)

1330 Monday

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Model products Winds forecast loop (knots)

1400 Monday

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Model products Winds forecast loop (knots)

1430 Monday

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Model products Winds forecast loop (knots)

1500 Monday

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Model products Winds forecast loop (knots)

1530 Monday

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Model products Winds forecast loop (knots)

1600 Monday

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Model products Winds forecast loop (knots)

1630 Monday

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Model products Winds forecast loop (knots)

1700 Monday

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Model products Winds forecast loop (knots)

1730 Monday

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Model products Winds forecast loop (knots)

1800 Monday

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Winds - Uncertainty in wind prediction From convective scale ensembles

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Model products Wave forecast (metres)

1400 Monday

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Weymouth Bay Nothe - Wind Forecast

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Wind Direction & Delta Wind Speed Wind Gusts

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Portland Harbour - Wind Forecast

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Weymouth Bay West - Wind Forecast

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Wind Direction & Delta Wind Speed Wind Gusts

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Warnings Board

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Tuesday’s Weather

Forecast Tuesday 1300 Gradient Wind forecast Tuesday 1300

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Summary and uncertainties

• Surface winds SW (230-260) 12 G 15 KT increasing to 15 G 20 KT

• Variability in direction, backing then veering later.

• Tuesday – Warm front approaching, SSW 10-12 KT becoming SW 12-15 KT. Light rain, drizzle, low cloud.

• Wednesday – Light/very light gradient wind and low cloud, poor visibility.

• Thursday – light easterly gradient wind, good sea breeze signal.

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Questions & answers

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Forecast products

• http://www.metoffice.gov.uk/loutdoor/olympics/event-manager/(General Weather Forecast, Race Areas Forecasts, Hourly Updates)

• This powerpoint brief is only available via the ISAF website.www.sailing.org/olympics/london2012