Testing the Wind (No Sail)
August 19, 2018
One goal in building this website is to provide as complete a
manual as I can for sailors who want to take up sailing on
Pittsburgh's rivers. A key part of manual is the presenting of how
various wind conditions manifest at the water's surface.
The page Summary
of Winds presents in tabular form how various unobstructed
winds convert into wind conditions on the rivers' surfaces. The
table covers all directions: North winds, Northwest winds, West
winds, Southwest winds and so on all the way to East winds. The
conditions described are all recovered from real experience
sailing on the rivers with just those winds. The table gives links
to the narratives from each of those sails.
There is one omission in the table. There are no entries for
Northeasterly winds. That is a curious omission. In my ten years
of sailing each summer on the rivers , I've never had a chance to
sail in Northeasterly winds.
Today looked like it might be that chance.
The National Weather service forecast steady Northeasterly winds
at 5 mph through the afternoon.
The windfinder superforecast was similar. Ominously, it showed a
dip in the speed of the wind mid afternoon.
I'd sailed yesterday and that left my muscles feeling sore. I
wouldn't normally sail on the following day. The winds were also
weak. 5 mph is the bare minimum for a fun day sailing. But then
this was my first chance in a decade to probe winds from the
Northeast. So I collected my sailing gear and set off on my
bicycle.
It was, in the end, a disappointing excursion. The dip in the
winds did come midafternoon just when I arrived at the marina,
around 1:30 pm. I measured, waited and watched for an hour and a
half.
The winds on the river fluctuated in strength and direction.
Sometimes the winds blew with the current, sometimes against it.
The speeds were between 0 and 4 mph, as revealed by my wind gauge.
The river surface sometimes showed glassy patches with no wind
and sometimes ripples going every which way. This was not well
directed wind, but turbulent breezes blowing in many directions.
I kept an eye on the tops of the trees on the river bank. They
were mostly unmoving. They showed only gentle wind movement now
and again.That meant that the slight winds on the river surface
reflected an overall weakness in the unobstructed winds.
These are not conditions for sailing. So at 3 pm, I hopped back
on my bicycle and headed back home.
The fountain at the Point was showing little wind.
The water at the Point showed glassy patches of dead air.
The winds on the Allegheny were a little more consistent. I
measured speeds of around 3 mph blowing from the Northeast along
the river course.
Here's the record of winds kept by the National Weather Service:
I was unlucky with the winds. I had set out to sail during the
short gap in the winds recorded at 2 pm and 3 pm (see 13:51 and
14:51 military time).
What did I learn about conditions for sailing with Northeasterly
winds? Northeasterly winds align roughly with the course of the
Allegheny river. I expect them to blow there, relatively
unobstructed. Today I had found the best winds there. Later in the
day, I went for a run along the Allegheny river and, around 6 pm
did find some nicer gusts of wind blowing with the current. That
coincides roughly with the National Weather Service report of
Northeasterly winds of 6 mph at 17:51.
With Northeasterly winds, the conditions will, I suspect, be poor
on the Mon and Ohio river. They are both flanked by a high ridge
on their Southwestern banks. Northeasterly winds blow across both
these rivers towards the rigde. I expect that will be deflected
upwards by the ridge. That could leave a pool of dead or turbulent
air on the Mon and Ohio river's surface.
I think this last effect is what I saw traces of today on the
Ohio river. However it is quite hard to be sure. The winds were so
slight during time that I observed that the poor conditions may
merely reflect the lightness of the winds.
John D. Norton
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