Telcoinabox Airlie Beach Race Week - Day 6 forecast

by Kenn Batt on 16 Aug 2012 Telcoinabox Airlie Beach Race Week - Day 6 forecast: Nil Warnings current at time of writing for the race area.

Synoptic Discussion: A high currently centred over the Coral Sea and moving slowly east, is extending a weakening ridge along the Queensland coast.

Observations:

At 0700hr Hamilton Island was reporting the following conditions:

Wind 170deg at 09kn (ave) gusting to 11kn, Temp 18C, Pressure 1020hPa).

Forecast Winds for Middle of Pioneer Bay (Read Discussion below)

1000:MD140 DR(170-130) MS10 SR04-15kn
1200:MD120 DR(140-100) MS10 SR04-15kn chance of 'glassout'
1400:MD100 DR(120-080) MS12 SR06-16kn could see 040deg?
1600:MD090 DR(110-070) MS12 SR07-17kn could see 030deg?

Whitsunday Passage and Molle Channel: Wind speeds 2 to 5kn stronger and 20deg more right in places at times than those forecast above this morning, before easing during late morning/early afternoon. Localised patchy winds developing from early afternoon. Winds could be gusty and erratic around some headlands and in more constrained locations.

Note : First column is mean wind direction in deg Magnetic (MD). It is the 10min average (mean) value at a height of 10m above the water leading up to the hour quoted. The second column is the directional range (DR) of the wind direction in deg Mag. This takes into account the natural oscillation of the wind and is a function of the atmospheric stability, etc. The third column is the mean speed (MS) in knots (kn) and is the average 10min value leading up to the hour quoted at a height of 10m above the water. The last column is the wind speed range (SR) in knots and is the lowest wind speed to highest wind speed in the 10min leading up to forecast hour.

Discussion: Today should see a light-moderate W-SW land breeze inshore early this morning, being replaced quickly by a moderate synoptic SE’er during the morning. The direction is then expected to trend left (or move toward the east and northeast) during the afternoon. The wind could become quite patchy at times especially in Pioneer Bay from late morning? A late morning 'glassout' to a sea breeze is possible in Pioneer Bay today?

Other possibilities: 60% chance that there is a 'glassout’ in Pioneer Bay this morning followed by an E-NE sea breeze at 8-12kn (ave)?

Note: Wind will be lighter in the lee of any landmass and stronger and more gusty between islands (in channels and passages) and around some headlands.

Natural oscillations today around 15 to 25 deg away from effects of topography, trending 30 to 50 deg closer to the effects of any land mass (including islands and headlands).
Weather: Cool at first with the chance of the odd early fog or low cloud around, clearing to a fine and sunny day.

Maximum land temperature at Airlie Beach: about 24 degrees.

Wind Waves: 0.3 to 1.0 metres. Less in lee of land, more when wind wave opposes tidal current and further offshore.

(Wave heights quoted are significant wave heights).

Tide at Shute Harbour: High of 2.67m at 0945hr, Low of 0.42m at 1533hr

Tidal Stream: A strong ebb for your racing today. Be very careful particularly in passages, channels, close to islands, etc.

Remember: Tidal currents generally flood to the south and ebb to the north in the Whitsundays (with a multitude of local effects and eddies. So be Airlie Beach Race Week website