North wind direction in degrees [Withdrawn]

I prefer to use 360° for a north wind, as shown under the wind direction dial on WD main screen, but the tag %dirdeg% (used in customclientrawlocal.txt) uses 0° for north. I did search the tagslist file but can’t find anything else for current wind direction.

Would it be possible to add a wind direction tag that uses 360° for north?

LATER EDIT: See below. . . suggestion withdrawn.

Why 360 degrees? Wind direction is 0 to 359 degrees so I don’t think that 360 degrees is a valid value, other than being just as valid as 720 or 1080 degrees and so on.

Just one quote for starters: “By convention, north is represented as 360° rather than 0°, as ‘0’ is reserved to indicate calm.” Stephen Burt (2012) The Weather Observer’s Handbook, p.195. Cambridge University Press.

There are other references out there, I’m sure. (And, while it’s nothing to do with wind direction, as a navigator I would usually tell the helmsman - that’s usually me, too - to steer three-six-zero rather than zero-zero-zero. . .)

I’ve been playing with my PWS dashboard to show zero in calm conditions (the wind has been cooperating) and 360° for north, just wondered if I can get SSGauges to do the same :wink:

Having searched for “What is north wind in degrees”, some say 360º and some say 0º

Interesting that ‘0º’ is reserved for calm, just because there is no wind speed doesnt mean that the direction should disappear, its probably still pointing to the last wind direction so shouldnt that be the direction stated, also ive seen my direction move in what I feel is a dead calm and not register any speed, probably around sub 1mph, i.e. 0.4mph.

Personally I feel that regardless of the 360/0 degree issue in this post, if it is Calm (no Wind) how can one expect to determine a direction if there is no wind.
Simplistically :


if (windspeed > 0.0) {
set_direction(to_direction);
} else {
set_direction(Calm);
}

But that is just my thoughts.

I suppose there is an earlier ref here to the Nautical Side :

So :

Relative bearing is similar to navigational bearing. In this case, however, we’re not calculating degrees between north and the destination. It’s between the heading of the vessel and the destination. So your relative bearing could be 0 degrees if your heading and course are all aligned. But it could also be off if, as in our example, you need to navigate around an island. This is all based on the relative position to your boat at the time you calculate it. Where you are pointing relative to a given waypoint or destination helps you determine relative bearing.

When we refer to a relative bearing course it’s worth knowing where we start exactly. In this case you’re measuring in a straight line from the observation station of the vessel. You can measure to whatever object or point of interest you’re interested in from that point to get the correct figures.

When a lookout on a boat raises a warning about something, this is always done in a relative way. The lookout would never know the course of the boat and it would be irrelevant to their duties. Anyone serving as a lookout understands that the bow of his boat will always be 0 degrees and can work in a 360 degree circle, relative to the vessel, from there.

Kind Regards,

Might just “borrow” your suggestion of showing ‘Calm’ instead of ‘0’, if there’s room. Thanks :slight_smile:

Ah funnily enough, we had some calm periods today.

Regards,

I see yours is pointing north too, so i take it you’re using WLL, mine shows north with WLL too but it never did with the Envoy.

Hi Bashy,
I use Davis VP2 with Console no WLL.
I also use CumulusMX with the setting: “Zero Bearing: Use bearing zero when calm, Use zero for current bearing if speed is zero”.
Kind Regards,

Here you go. . .


calm2.png

Aha Perfect, looks brilliant.

I finally added same to both Current Direction (Cardinal), Current Bearing (Degrees) and 10 Min Avg Direction (Cardinal), 10 Min Avg Bearing (Degrees) and also created new icons code etc to display Calm Icons.

When time permits I might modify scripts to not show the Bearing (Degree Symbol) when Calm, that’s for another day.

https://beaumaris-weather.com/BWX/

Kind Regards,

Yeah, the Devil’s in the details. . . (Sorry, couldn’t resist it :wink:)

At present i have a calm and my Davis console shows the degrees and arrows of the last known direction. I cant be asked to go check but i am fairly certain my OS console also shows the last known direction too.

I think i would prefer it to say Calm to be fair but still keeping the last known dir arrow because that is very important to me, I need to know whether or not i need to close the conservatory door if rain is in the area, because the door is North facing any wind thats from the West, North or East, the rain comes in, so i prefer a visual direction reference all the time.

Iirc the Davis VP2 console shows the last direction until the average speed drops to zero?

The average direction arrow would still be there on the PWS dashboard.

I just noticed that Bashy’s PWS dashboard shows 360° for N while mine showed 0° until I modified the script. We both use WD clientraw.

I gather from this that it depends on the weather station. . . can anyone confirm that?

And, if that’s true, it probably applies to all custom tags as well and I apologise for wasting everyone’s time :oops:

My PWS2021 is showing 0º for North. This happens if WD is restarted when there is a calm from WLL.
Also WD will show North periodically for no apparent reason even when the windspeed is moving.
Its a dead calm now and the VP2 Console is showing 256º, its been calm for a wee while now as seen on the image, also, you can se what i mean when I said about the driection changing when no speed is reported, its quite clear on the image, so whilst the windspeed might be calm, the direction might not be. Baring in mind that mine shows from 1mph.


Screenshot 2022-04-14 010042.png

Screenshot 2022-04-14 005556.png

The minimum reported speed by the VP2 is 1mph but that doesn’t mean it’s not measuring lower speeds. So if there was a very gentle breeze of 0.5mph the cups may be moving but the speed will be reported as zero. If the cups are moving in the breeze then the vane will probably move too giving you a change in direction even though it looks like there’s no wind.

This is certainly a no movement from the cups scenario from my observations, this morning when i posted this it was a dead calm, foggy, to be honest i have never seen my cups turn and not register at least 1mph, perhaps my cartridge is ready to be renewed, i have just watched it out the window, the cups couldnt have gone any slower, literally creeping and it showed 1mph, then the cups stopped, at the minute its easy to check cause its not gone over 3.6mph. When i said i have seen it where the cups were not moving but the vane did, i meant the cups were dead in the water. I was outside at the time and happened look at the anny to noticed the dir change with dead in the water cups, this prompted me to reply at the time i did. :slight_smile:

Just took another snippet from today cause it shows it better, see that wind dir change at around midnight with 0 speed, that was a larger movement than the one at around 7:15am that moved @ 1.2mph, like i say, its probably time for a new cartridge or spiders are moving in again…


Screenshot 2022-04-14 082009.png

I’ve no scientific facts to back this up so this is just an opinion.

I think it’s probably easier for a very gentle, under 1mph, breeze to move the vane than it is for that same breeze to move the cups. The vane just needs a bit of pressure on one side or the other to move it. I think the amount of wind needed to get the cups moving is higher than needed to move the vane, particularly if the cups are in certain positions when they stopped. Cups work well at higher wind speeds but, in my opinion, not so well at lower speeds.

Having said all that, is it really that important to measure the wind speed or direction at very close to zero speed? Low wind speeds don’t damage anything and the direction doesn’t make any real difference if there’s next to no wind. You said you’d like to know so that you can shut the door in case rain blows in from specific directions, but if the wind speed is so low then rain can’t blow in, it will just fall vertically and not get into the door.

To a human, the difference between 0, 1 and 2 mph isn’t significant. Nor is the difference between 50, 51 and 52 mph. I’ve seen lots of people over the years get concerned about the absolute accuracy of their measurements when it’s very rare that the difference that’s being worried about would make any difference at all. I can see that temperature accuracy would have an impact in climatic measurements where we’re worried about 1 or 2 degrees having a huge impact on the planet, but to the average weather observer with a non-ideally located station that’s not something they could really measure anyway. So what if I can measure temperature to one hundredth of a degree if my sensor is in a position that is always 2 degrees higher than most of the surrounding area. In my opinion wind speed and direction are even less important than an accurate temperature.