Topic: "Feels like" too hot?

[tedroche]

I'm in the process of setting up Saratoga templates at https://contoocook.org and I've got a glitch in the "Feels like" display.

Temps are in the mid-80's in northern New England, but the "feels like" is flirting with 100 Fahrenheit on the ajax-dashboard.

I'm running Ecowitt hardware and a WeeWx backend, and "Feels like" more reasonably shows only a few degrees warmer than actual temp on the gateway GW1100 web display and on the plain vanilla WeeWx site I run at wx.iayft.com. The WeeWx backend uses the gjr80/WeeWX-Saratoga extension 0.1.9 to create the clientraw.txt file, and the rest of the displays seem consistent with what I'm observing locally. All Saratoga template versions are confirmed up to date.

Any suggestions on how to troubleshoot this would be welcomed!

[saratogaWX]

The default for 'feelslike' is to display humidex when the temp is >27C.

This is in ajaxWEEWXwd.js

      // FeelsLike
      temp = clientraw[4]; // note.. temp in C
        if (temp <= 16.0 ) {
        feelslike = clientraw[44]; //use WindChill
      } else if (temp >=27.0) {
        feelslike = clientraw[45]; //use Humidex
      } else {
        feelslike = temp;   // use temperature
      }
      var feelslike  = Math.round(convertTemp(feelslike));
        set_ajax_obs("ajaxfeelslike",feelslike + uomTemp);

You can change to use heat index by changing

feelslike = clientraw[45]; //use Humidex

to

feelslike = clientraw[112]; //use heat index

That will change the display when the AJAX script starts running and updates the display with the heat index.

The $feelslike data in WEEWXtags.php produced by WeeWX will continue to upload humidex into that value.
You'll need to ask the WEEWX user group how to change it to use heat index instead.

[tedroche]

Ah! Thanks for the explanation. I made a poor assumption that the same number was being passed through and somehow mangled. I'm glad it's not something I misconfigured.

[92merc]

The default for 'feelslike' is to display humidex when the temp is >27C.

The $feelslike data in WEEWXtags.php produced by WeeWX will continue to upload humidex into that value.
You'll need to ask the WEEWX user group how to change it to use heat index instead.

Can WD ajax be similarly changed to show heat index instead of humidex?

[Vasco]

Can WD ajax be similarly changed to show heat index instead of humidex?

Looks like it, around line 712: heat index is WD clientraw[112]

[92merc]

I've updated my ajaxWDwx.js from 45 to 112. It didn't break. 

[Vasco]

I've updated my ajaxWDwx.js from 45 to 112. It didn't break. 

I had already changed the next line from feelslike=temp to clientraw[130]. I didn't see why FeelsLike should show the actual temp between 16° and 27°C, so it now shows WD Apparent.

And, as I believe WindChill is only valid below 10°C, I changed the <= 16 too. . .

EDIT: In WD you can uncheck "Calculate windchill above 10°C" with the rider "(except for clientraw data)". I think this means that you don't get windchill shown in the main screen "Current Conditions" - but you do get windchill in clientraw, and you certainly still get it shown on the main screen graphs 

[tigerbait]

I've tweaked my ajaxWD.  Do you have to change anything in WD itself?
Thanks
Alan

[Vasco]

Do you have to change anything in WD itself?

No, clientraw has all these different values anyway.

[tigerbait]

Thanks you.  These adjustments cooled my heat index down to about where it should be.

[Vasco]

Do you have to change anything in WD itself?

No, clientraw has all these different values anyway.

Just noticed what Ken said about $feelslike in WEEWXtags, so presumably the same happens in testtags?

Code: [Select]

$feelslike =  '11.9'; // Shows heat index or humidex or windchill (if less than 16oC)

But I don't understand why it matters. . . 

[saratogaWX]

It only matters for what the page shows when first loaded (data rendered by PHP tags file).  If NO JavaScript is enabled in the browser for that site, then that is what the browser sees.
When the AJAX script starts execution, the feelslike value will change to the heat-index value from the humidex value.

Weather-Display has historically used humidex for feelslike.  The weewx plugin replicates that.

In WD, Control Panel, Units, Temperature TAB, you can UNtick "Show humidex instead of heat index or windchill"

The WeeWX change would involve changing the weewxWD python code for the WEEWXtags skin.

[Vasco]

It only matters for what the page shows when first loaded (data rendered by PHP tags file).

Phew! Thanks, Ken 

[gjr80]

It only matters for what the page shows when first loaded (data rendered by PHP tags file).  If NO JavaScript is enabled in the browser for that site, then that is what the browser sees.
When the AJAX script starts execution, the feelslike value will change to the heat-index value from the humidex value.

Weather-Display has historically used humidex for feelslike.  The weewx plugin replicates that.

In WD, Control Panel, Units, Temperature TAB, you can UNtick "Show humidex instead of heat index or windchill"

The WeeWX change would involve changing the weewxWD python code for the WEEWXtags skin.

For those that wish to change the WeeWX behaviour I've released v0.1.10 of the WeeWX plugin that now includes the ability for the user to specify a simple source observation to be used for the feelslike tag in WEEWXtags.php. You can now edit skins/WEEWXtags/skin.conf and under the banner add an [Extras] stanza with a feelslike option as follows:

Code: [Select]

[Extras]
    feelslike = heatindex | windchill | humid | apparent
Setting feelslike to one of the listed options will use the current value of that observation to set the feelslike tag in WEEWXtags.php. If the option is not set or is omitted, the existing testtags multi-source based formula for feelslike will be used. You can also define an [Extras] stanza and feelslike option under [StdReport] [[WEEWXtagsReport]] in weewx.conf as follows (note the additional brackets):

Code: [Select]

[StdReport]
    ....
    [[WEEWXtagsReport]]
        [[[Units]]]
            feelslike = heatindex | windchill | humid | apparent
    ....
This change will require a WeeWX restart for it to take effect, changing skin.conf does not require a restart. Note also that placing such settings in weewx.conf is the preferred approach as such changes survive extension upgrades; changes to skin.conf will not survive an extension upgrade.

This addition changes the feelslike tag in WEEWXtags.php only, it makes no changes to any of the clientraw files, Saratoga template files (including javascript).

v0.1.10 of the WeeWX plugin can be found on GitHub here.

Gary

[saratogaWX]

Thanks, Gary!  That's a nice addition.