Wind speed at constrictions/narrows

Hi there,
not too long ago on a paddle where our journey was from A to B. The wind was from the indicated direction and was picking up, F3/ F4. we chose the red route which was calm & wind free.

At point X, the wind was such that we could barely make progress.

My question is , if we had taken the blue route , and kept away from the tip of the cape, would the wind have been less ‘concentrated’ and easier to paddle in? thanks

windQ

Winds probably would have been less at point Y than point X, but you would have had stronger beam winds and waves at other points on the blue track the further you moved out from the wind shadow of the land mass. At point X the wind is likely curling around the point and becoming more concentrated.

My guess is the main influence of those palisades would be from the wind going over the top and maybe reversing back toward the shore a little along the surface. There would be some funneling around the tip but not much. I’d be more concerned with wave height over any shallows at the tip as a reason to choose route Y.

Yes, it’s a bit risky to generalize since complex airflows sometimes do strange things but I think that in principle Point X could be in a low pressure zone created by the wind blowing over the ridge next to it and a low pressure zone could “pull” the air around the point and accelerate the airflow.

Personally I cannot see the wind shadow line based upon the information given. It likely is in-between the two courses, but it changes with hill tops irregularities. You’d be looking for a change in the texture of the surface of the water. I would have expected the wind to be stronger at the point where it gets bunched up then rounds the corner.

I would have paddled just inside the shadow similar to red then paddled on through the corner to align up on the waves with the wind on the port bow. Falling off at ‘x’ a little towards ‘y’ might help at the “rounding” but you don’t want to be too far downwind of your course to point B.

My boat does not beam winds well.

My forecast would be for course Y.
Here’s my reasoning.
First off, staying close to shore until reaching point is likely a better path, but unknown from the image is the height of the cliffs. At some point the wind speed will have a katabatic influence and the wind speed would pick up as it fell down the cliff due to gravity. But that usually requires a significant amount of elevation difference (thousands of feet) before that would happen, and thus more likely is a vertical wind eddy with gusty conditions coming back to shore.

The major influence would occur at the point. The wind going over the top of the island would slow down due to friction with the land, and when that happens it will change directions and point more towards the wind generating low (backing wind). This is assuming that the prevailing wind coming towards the island has been coming over some distance of open water - the low will likely be in the direction of B (look up Buys Ballot Law).
And that means the prevailing wind over the water at the point will combine with the backed wind coming off the point of the island, a potentially nasty converging wind situation. It would lessen the farther one is from the island.

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Point Y might also have more sea chop depending on currents as the wind has a longer catch on the water. Need to pick your poison. Does wind or sea impact your boat more? Easy to make a theory from just a picture.

I can’t think of better strategies than the above suggestions. Less experienced paddlers may conclude that picking the proper course is complicated and scary - it is. Properly outfitted experienced paddler will simply read the conditions, pick the best line, power through it, or jump into the gnarly mess to play.

I’d like to offer first time paddlers basic information that may help with planning and decision making.

Always consider the body of water, current weather conditions, the forecast, and be familiar with local weather anomalies. Dress for the conditions and always WEAR all protective gear for the conditions. If practical, accompany an exerienced paddler from that area and discuss paddling tips, while watching the cute duckies

In general, wind affects paddle boards, sit-on-tops, canoes, and closed kayaks in that order. Wind at 10 mph, may impact speed by .1 mph. Blowing overnight at that speed can create a .5 mph current. Wind typically (not always) increases during the day and falls with evening, so consider if a trip track includes open terrain or distance from protected shores. Take advantage of terrain features that offer a wind break, but wind can curl in opposing direction around heights or intensify near openings. Waves traveling in the same direction as a tide will peak higher when the tide changes to flow against the wind. Waves will grow higher and may transition from rolling to breaking peaks at shorter intervals when they aproach shallows. Obviously, the longer the unobstructed wind or current travels, the more force it builds. Short boats are inherently slower, and tall waves will cause it to climb and plunge more than a long boat. Consequently, the shorter boat will reach a point where progress is no longer possible, regardless of power applied.

Current influences speed one to one. River current or
tides will essentially increase or decrease speed by the same amount. Side currents cause drift. Shallow water increases drag and intensivies the power and height of waves. Falling tides can expose seaweed or shoals that were otherwise passable on the outgoing track. Constricted areas will increase current speed, especially during reversing tides.

The tips may be common sense, but they’re important to consider when planning a trip or while making descision to go further than originally planned. Hope it’ll increase your confidence and enhance your safety.

Water surface tells you most all you need on the wind.

How big were the waves?

Agree PaddleDog52, especially the catpaw ripple in the swells that show up with winds over 10 mph and the distrbution of whitecaps. I also recently notice parallel foam bubbles about 20 ft apart that show wind direction when the wave action increases.


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Nice observation - these are usually called ‘windrows’, and are evidence of Langmuir Circulation — arrays of fairly low speed counter-rotating horizontal vortices in the upper layer of water at the ocean surface. The vortex axes are aligned parallel to the overall wind direction.

Langmuir circulation - Wikipedia

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Dang, carldelo! I’ve noticed the foam, but have haven’t given it much thought until recently. I’ve been paddling the same track this year, while monitoring every condition closely. That’s how I saw it over and over. The signs often conflicted with reported speed and direction, which made me realize that weather reports are only reliable for the reported location. The only accurate method is what other members are explaining. You have to look at the water and read the signs.

What puzzles me is how rarely follow up questions are posted to explore further details. Is it because everybody else has already figured it out, other readers just take note of what has been pointed out, or is there a fear of appearing inexperienced. I also learned how to read clouds around my region, so I have between two and three hours to anticipate the arrival of storms, even before there’s warnings on weather reports or evidence on radar. Those piloting sail boats probably have the keenest sense of the awareness regarding weather patterns and changing conditions.

Many thanks for the information.

Get a kestrel meter.

That’s too much like work. You don’t need that.

If you want the weather for your location nothing is better. What work is a meter?