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Summary of Winds

When the weather forecast predicts winds from the South West, for example, will that mean that sailors on the river surface will experience a South Westerly wind? In general, the unobstructed winds of weather forecasts and high in the air will differ from what sailors find. The reason is that these winds are deflected by hill, ridges and tall buildings around the Point. So wind at the water's surface can differ significantly from the forecast winds, even if the forecast is correct.

After several seasons sailing on the rivers around the point, I have collected enough experience with different wind conditions to know which which wind conditions arise at the river surface from the various unobstructed winds. They are summarized in the table below. For more details on how I determined the wind conditions on the surface, see "Decoding the Winds." The major finding is that hills and buildings on the river shores tend to redirect winds to blow along the rivers, either directly upstream or downstream. Hence they are often reported in that way in the table.

The rivers around the point have been divided into four regions indicated on the map below.

river sections

A few rules of thumb will answer many questions:

The best wind on each segment of the river comes when the unobstructed winds blow exactly along the length of the river.
The section of the Allegheny river marked above is aligned roughly West-South-West to East-North-East. A West-South-West wind will give the best sailing since it will blow unobstructed along its length.

There are wind shadows in the lee of anything big.
The same West-South-West winds will be obstructed by the high ridge along the Western shore of the Ohio and Mon, so that winds will be erratic close to that shore.

Sailing works best with unobstructed winds over 5 mph.
Below that speed, obstructions and natural variations in the wind will leave a lot of periods of calm. The conditions I like best come at 10 mph for unobstructed winds. By 15 mph (when whitecaps form), there are likely to be erratic and strong gusts that make sailing hard work.

 

Unobstructed winds   Ohio River The Point Allegheny River Monongahela River Sailing day with (near) matching wind
North N   Winds blow upstream. Experience includes steady winds and erratic winds. Winds can be erratic; obstruction from buildings on North shore. Winds can be erratic; obstruction from buildings on North shore Winds generally blow upstream, but can be erratic in places. August 27, 2011 N
July 21, 2012 N
            June 27, 2009 NNW
September 13, 2009 NNW
June 17, 2010 NNW
July 30, 2011 NNW
North West NW Best overall wind conditions for sailing on all regions. Winds blow steadily upstream. Winds blow steadily upstream, dividing at point. Erratic winds blow upstream; periods of calm possible Winds blow steadily upstream. August 11, 2011 NW
August 16, 2011 NW
June 26, 2012 NW
August 1, 2012 NW
September 9, 2012 NW
September 3, 2012 NW
            July 8, 2009 WNW
August 6, 2010 WNW
August 16, 2010 WNW
June 13, 2011 WNW
August 7, 2011 WNW
West W   Variable. Winds may be blocked by hills on southern shore. Winds blow steadily upstream, dividing at point. Winds blow steadily upstream Winds tend to blow upstream; some erratic wind possible. August 21, 2011 W
            August 9, 2009 WSW
August 29, 2009 WSW
June 27, 2010 WSW
July 24, 2010 WSW
September 5, 2010 WSW
South West SW Best sailing is on the Allegheny. Winds blocked by hills on southern shore; erratic. Winds can be funneled into rivercourse through valley at West End Bridge and spread from there into upstream and downstream directions. Erratic winds; obstruction from hills on southern shore. Winds blow steadily upstream Erratic winds; significant obstruction from hills on Southern shore. Winds may even blow momentarily from NE! July 17, 2010 SW
July 18, 2011 SW
August 13, 2011 SW
September 4, 2011 SW
June 30, 2012 SW
August 17, 2012 SW
July 23, 2013 SW
            June 22, 2011 SSW
August 6, 2011 SSW
South S   Winds blocked by hills on southern shore; erratic. Winds blocked by hills on southern shore; erratic.     September 29, 2013 S
             
South East SE Best sailing on the Ohio and Mon. Winds blow steadily downstream. Winds blow steadily downstream. Erratic; obstructions from buildings on Southern shore. Winds become more erratic farther upstream. Winds blow steadily downstream. September 11, 2010 SE
September 3, 2012 SE
August 17, 2013 E and SE
            September 6, 2009 ESE
East E*   Winds blow downstream Winds blow downstream Winds blow downstream   July 14, 2011 E
August 26, 2012 E (and SE)
August 17, 2013 E and SE
North East NE            
Unobstructed winds   Ohio River The Point Allegheny River Monongahela River Sailing day with (near) matching wind

*Experience on several days suggests that the forecast of Easterly winds is unreliable. These winds tend to arise only for a short time while wind direction changes. The forecasters seem to have trouble locating accurately the window in which the Easterly winds come. See July 14, 2011 and July 21, 2012.