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Sky Conditions
Posted: Tue 30 Jun 2020 2:14 pm
by 92merc
It would be nice if Cumulus could create it's own sky conditions if you have solar/UV sensors. Similar to what WeatherDisplay does. Makes loading of my webpage faster with Saratoga scripts when that is included in the live conditions file.
Re: Sky Conditions
Posted: Tue 30 Jun 2020 4:12 pm
by mcrossley
What does WD do with solar data to produce a sky condition?
Re: Sky Conditions
Posted: Tue 30 Jun 2020 7:26 pm
by saratogaWX
Weather-Display uses a couple of methods to pick an icon/sky/weather condition:
1) a nearby METAR can be used for Sky conditions.
2) for daytime, with a solar sensor, the cloud conditions can be estimated by comparing the current solar value with the extimated max value (for lat/long, time).
The % of max value then can have words set (along with the corresponding icons).
3) a stations local rain/wind/fog can override either of the above methods.
I've attached the Solar config panel from current WD so you can see the settings/descriptions I currently use with my Davis VP system.
Hope this helps...
2020-06-30_solaricon.png
Re: Sky Conditions
Posted: Tue 30 Jun 2020 7:50 pm
by Mapantz
I'm sure Mark has a backlog of things to be added as well as having a life, but I have to admit, if CMX could produce an image/text output to show current conditions, I would be quite excited!

Re: Sky Conditions
Posted: Tue 30 Jun 2020 9:52 pm
by beteljuice
"current conditions" scripts jennyleez
viewtopic.php?f=14&t=12831 (PHP) and BCJKiwi
viewtopic.php?f=18&t=17845 (javascript) both contain code for using solar data for cloud cover - during daylight hours obviously !
Here is the JS version - checks have already been made for:
1 Rain
2 Fog
3 Twilight
any of which set suppress = 1;
Code: Select all
if(display.showCloud) {
if(realtime[56] > 0 && realtime[49] == 1) { // if NOT night
if(realtime[45] < 1) {
SolarRad = 1; // prevent any possible division by zero
} else {
SolarRad = realtime[45];
}
var skycond = (realtime[56] / SolarRad);
var sky = "";
switch(true) {
case skycond < 1.2:
sky= data.langSkyCond.clear;
break;
case skycond < 1.6:
sky= data.langSkyCond.mostlyclear;
break;
case skycond < 2:
sky= data.langSkyCond.scattered;
break;
case skycond < 2.5:
sky= data.langSkyCond.partcloud;
break;
case skycond < 3:
sky= data.langSkyCond.mostcloud;
break;
case skycond < 3.5:
sky= data.langSkyCond.cloudy;
break;
case skycond >= 3.5:
sky= data.langSkyCond.overcast;
break;
}
if(suppress == 0){
auto += (auto ? ", " : "");
auto += sky; // NB: skycond now concatated to $auto (.=)
}
}
}
Re: Sky Conditions
Posted: Wed 01 Jul 2020 2:13 pm
by mcrossley
I don't intend to go adding checking METARs to Cumulus, so it could only perform the daytime check for users with solar sensors.
It also does not make sense to only check a spot value of irradiation, it would say cloudy when a cloud passed over even if the rest of the sky was clear. The reading may well be higher for broken high cloud than a clear sky with the odd cloud as well. Using average values over a say half hour period would be better, but it's still in the area of finger in the air with your eyes closed whilst wearing a glove though.
Much better to invest in a proper radar unit I think!

- or maybe just a METAR parser for your local station

Re: Sky Conditions
Posted: Wed 01 Jul 2020 2:33 pm
by sfws
mcrossley wrote: ↑Wed 01 Jul 2020 2:13 pm
I don't intend to go adding checking METARs to Cumulus
...
- or maybe just a METAR parser for your local station
Well as author of the best METAR parser, I'm glad to see that I'm not getting a rival (although mine needs an update, and it is somewhere on my to do list).
Seriously, the availability of METAR information in UK (and probably most countries outside America) is limited, both in terms of not enough locations (except in UK if you are close to a RAF station or major airport) and in terms of what is output. In another topic, someone in Farnborough area was complaining that Current conditions could not be obtained from its METAR, and when I checked a number of other UK METARs I found actually very few did supply the information in the way that I suspect Weather Display and a few other third-party pages need.
It took a long time for USA to adopt international METAR content guidance, and they still don't fully follow that, and I suspect it will be a long time before they fully move to the new system they are testing that is now the international standard. Yes, once again I will remind everyone, traditional alphanumeric MEATAR are already being phased out, so there is no point in adding that functionality anyway. From my experience of asking UK pilots, they stopped using traditional METAR several years ago, they use the new system that gives weather conditions along their full proposed flight path.
Both ICAO and WMO have for many years been forcing all aerodromes to report in the format that feeds into the new system, it uses geographic XML (i.e every parameter is tagged with both what it represents and where it was measured. If you want to know more, my guide remains available somewhere on this forum and was referenced again only a couple of months ago I believe.
Re: Sky Conditions
Posted: Wed 01 Jul 2020 7:01 pm
by 92merc
What I like about WD is it not only gives sky conditions, but it'll say "cloudy, raning" "partly sunny, stopped raining" or "night time, dry". So its both sky conditions and rain/no rain. So it's a little more verbose than the local METARS.
That and my local METAR conditions can be an hour old or more. WD puts in the condition about every 10 minutes. Which is good by me.
Re: Sky Conditions
Posted: Thu 02 Jul 2020 5:47 am
by BeaumarisWX
Hi all,
I had a little chuckle when I read this post, I recall ages ago beteljuice making a comment in a reply to me
viewtopic.php?p=105354#p105354 "You have a webcam thumb - What more do you need

".
At that stage I lived in South Franklin Tas, way too far away from nearest Metar (Hobart) to be anywhere near relevant. Now I live in Beaumaris Tas (same deal) Metar way too far off.
I still cross ref both Jenny Lees and Brian's script on my alternate sites and it will be clear skies but scripts show overcast or Mostly cloudy etc. without using Metar input.
So I adopt beteljuice's recommendation from way back then, Webcam does not lie, only difficult to determine at night
https://beaumaris-weather.com/wxindex.php
Attempt 1:
sky.PNG
Attempt 2:
sky.PNG
Attempt 3: (hopefully final).
sts.PNG
Kind Regards,