Re: [weewx-user] Windchill Text Value / Graph Discrepancy

[gjr80]

Just to clarify, the linked post above dealt with an issue where the user 
noticed the wind chill value displayed on his Vantage2 console did not 
match the wind chill value displayed by WeeWX. The reason was the console 
displayed the value calculated by the console, but WeeWX displayed the wind 
chill value calculated by WeeWX (because LOOP1 packets were used by WeeWX 
the console windchill value was never seen by WeeWX so WeeWX calculated 
windchill - changing to LOOP2 packets sent the console calculated wind 
chill to WeeWX and WeeWX used this wind chill value rather than calculating 
wind chill). Different and unrelated issue to the problem outlined in this 
thread.

I agree with John's post; the issue is likely due to the loop_hilo setting 
and the source used for plots and reports. Native WeeWX plots are generated 
from archive table data. Archive records contain data for each observation 
that is representative of the archive period concerned, for temperatures 
this is typically the average value across the archive period. On the other 
hand, aggregates used in reports are based on the daily summaries which, by 
default, do record max/min values for each day based on loop packet 
max/mins. Consequently, it is not unusual (in fact I would say it happens 
frequently) for a day plot to not accurately show the day max/min. This is 
usually not an issue given the low resolution of the WeeWX plots (ie you 
just can't see it), however, I could see situations where there is a 
noticeable difference (as in this case in this thread). In fact, when it 
comes to derived obs such as wind chill that are dependent on a rapidly 
changing observation such as wind speed, it is quite possible there would 
be a noticeable difference between the day min value shown on a plot and 
the day min value shown in a report.

You could likely get rid of the discrepancy by changing loop_hilo to False, 
it's a personal preference, but you have to accept then your system will no 
longer record the max/min values seen in loop packets, rather it will 
record the max/min archive period average values. My preference is to have 
loop_hilo = True to record the loop highs and lows so my reporting is 
accurate and accept the occasional plot discrepancy.

Gary

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Re: [weewx-user] Windchill Text Value / Graph Discrepancy

[Steve Schindler]

My apologies. I probably could have phrased that better. You are correct 
that VP2s can generate windchill via hardware; however, an older unit like 
mine with older firmware doesn't send the windchill value in the LOOP 
packets.  

On Tuesday, January 3, 2023 at 9:39:03 AM UTC-5 jo...@johnkline.com wrote:

> > Tom and Gary confirmed that the VP2 hardware generated values for 
> windchill are only available in the LOOP2 packets.
>
> I’m not sure why you think that is relevant.  The question is, whether 
> software or hardware generated, do the loop packets have windchill.  I 
> confirmed they do contain windchill (for my VP2) before my initial reply.
>
> On Jan 3, 2023, at 6:06 AM, Steve Schindler  wrote:
>
> 
>
> Thanks for the suggestion but I don't think that's the issue with my 
> setup.  In a previous discussion (
> https://groups.google.com/g/weewx-user/c/roOG0u8YPX4/m/Tc4vWnznAgAJ), Tom 
> and Gary confirmed that the VP2 hardware generated values for windchill are 
> only available in the LOOP2 packets.
>
> ---
> tke...@gmail.com
> Jul 24, 2020, 8:21:48 PM
>
> to weewx-user
> Geez, Gary, you're right! So, you would also have to specify LOOP2 
> packets. See the section [Vantage] 
>  in the User's Guide.
>
> [Vantage]
>   loop_request = 2
>
>
> -tk
>
> On Fri, Jul 24, 2020 at 5:13 PM gjr80  > wrote:
> Windchill is only in included in the Davis LOOP2 packet, it’s not in the 
> LOOP packet or archive record (the defaults) from the console. So unless 
> you have set WeeWX to use the LOOP2 packet WeeWX will never see windchill 
> from the console, irrespective of StdWXCalculate settings.
>
> Gary
> ---
>
> And the User's Guide states "Not all stations support LOOP2 data. You need 
> firmware version 1.90 or later."
>
> So I don't think the loop_hilo parameter will affect the windchill value 
> with my setup.
>
>
> On Saturday, December 31, 2022 at 1:07:01 PM UTC-5 jo...@johnkline.com 
> wrote:
>
>> Tom and friends will know for sure, but I believe the low you are seeing 
>> (at 07:31) is from the archive_day_windchill table.
>>
>> You likely have the following in your weewx.conf
>> # Whether to include LOOP data in hi/low statistics
>> loop_hilo = True
>>
>> This tells weewx (well, it tells it to do exactly what the comment says). 
>>  Note: vantage loop packets do indeed include windchill.
>>
>> The archive table (produced from vantage archive records) does not 
>> include this low and the graphs are produced from archive records.
>>
>> I don’t think you are seeing anything *wrong*.
>>
>> Note: these highs and lows in the daily stats get wiped out if you run 
>> wee_database —rebuild-daily (which is unfortunate).
>>
>> On Dec 31, 2022, at 9:21 AM, Steve Schindler  wrote:
>>
>> During the recent cold weather, I noticed a discrepancy between the 
>> windchill minimum value in the table and the value/time shown on the graph. 
>> For 12-24-22, the Low Wind Chill in the Since Midnight table is 23.6F at 
>> 07:31, but the graph doesn't reflect that value. It shows a low of about 
>> 27F at about 8:00. For 12-25-22, the temperature discrepancy is about the 
>> same but time difference is greater. See the screenshots below. All other 
>> values (temp, humidity, wind) agree between the table and the graphs.
>>
>>
>>
>> I'm using a Davis VP2 with firmware version 1.82 so WeeWX is calculating 
>> the windchill value. 
>>
>> Any thoughts on what's happening and how it can be corrected?
>>
>> I'm in Florida so my troubleshooting/testing opportunities are limited to 
>> when a cold front passes through. However, I suspect that heat index has 
>> the same problem and, if so, I'll have plenty of time to work on that that 
>> this summer. :-)
>>
>> 12-24
>>
>> 
>>
>>
>> 12-25
>>
>> 
>>
>> -- 
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>> https://groups.google.com/d/msgid/weewx-user/183e065c-2fc6-4b2b-aaff-99ec35fa8ca1n%40googlegroups.com
>>  
>> 
>> .
>>
>>
>> 
>>
>> 
>>
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Re: [weewx-user] Windchill Text Value / Graph Discrepancy

['John Kline' via weewx-user]

> Tom and Gary confirmed that the VP2 hardware generated values for windchill are only available in the LOOP2 packets.I’m not sure why you think that is relevant.  The question is, whether software or hardware generated, do the loop packets have windchill.  I confirmed they do contain windchill (for my VP2) before my initial reply.On Jan 3, 2023, at 6:06 AM, Steve Schindler  wrote:Thanks for the suggestion but I don't think that's the issue with my setup.  In a previous discussion (https://groups.google.com/g/weewx-user/c/roOG0u8YPX4/m/Tc4vWnznAgAJ), Tom and Gary confirmed that the VP2 hardware generated values for windchill are only available in the LOOP2 packets.---tke...@gmail.comJul 24, 2020, 8:21:48 PMto weewx-userGeez, Gary, you're right! So, you would also have to specify LOOP2 packets. See the section [Vantage] in the User's Guide.[Vantage]  loop_request = 2-tkOn Fri, Jul 24, 2020 at 5:13 PM gjr80  wrote:Windchill is only in included in the Davis LOOP2 packet, it’s not in the LOOP packet or archive record (the defaults) from the console. So unless you have set WeeWX to use the LOOP2 packet WeeWX will never see windchill from the console, irrespective of StdWXCalculate settings.Gary---And the User's Guide states "Not all stations support LOOP2 data. You need firmware version 1.90 or later."So I don't think the loop_hilo parameter will affect the windchill value with my setup.On Saturday, December 31, 2022 at 1:07:01 PM UTC-5 jo...@johnkline.com wrote:Tom and friends will know for sure, but I believe the low you are seeing (at 07:31) is from the archive_day_windchill table.You likely have the following in your weewx.conf    # Whether to include LOOP data in hi/low statistics    loop_hilo = TrueThis tells weewx (well, it tells it to do exactly what the comment says).  Note: vantage loop packets do indeed include windchill.The archive table (produced from vantage archive records) does not include this low and the graphs are produced from archive records.I don’t think you are seeing anything *wrong*.Note: these highs and lows in the daily stats get wiped out if you run wee_database —rebuild-daily (which is unfortunate).On Dec 31, 2022, at 9:21 AM, Steve Schindler  wrote:During the recent cold weather, I noticed a discrepancy between the windchill minimum value in the table and the value/time shown on the graph. For 12-24-22, the
Low Wind Chill in the Since Midnight table is 23.6F at 07:31, but the
graph doesn't reflect that value. It shows a low of about 27F at
about 8:00. For 12-25-22, the temperature discrepancy is about the same
but time difference is greater. See the screenshots below. All other values (temp, humidity, wind) agree between the table and the graphs.
I'm using a Davis VP2 with firmware version 1.82 so WeeWX is
calculating the windchill value. Any thoughts on what's happening and how it can be corrected?
I'm in Florida so my troubleshooting/testing opportunities are limited to when a cold front passes through. However, I suspect that heat index has the same
problem and, if so, I'll have plenty of time to work on that that this summer.
:-)12-2412-25



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Re: [weewx-user] Windchill Text Value / Graph Discrepancy

[Steve Schindler]

Thanks for the suggestion but I don't think that's the issue with my 
setup.  In a previous discussion 
(https://groups.google.com/g/weewx-user/c/roOG0u8YPX4/m/Tc4vWnznAgAJ), Tom 
and Gary confirmed that the VP2 hardware generated values for windchill are 
only available in the LOOP2 packets.

---
tke...@gmail.com
Jul 24, 2020, 8:21:48 PM

to weewx-user
Geez, Gary, you're right! So, you would also have to specify LOOP2 packets. 
See the section [Vantage] 
 in the User's Guide.

[Vantage]
  loop_request = 2


-tk

On Fri, Jul 24, 2020 at 5:13 PM gjr80 https://groups.google.com/>> wrote:
Windchill is only in included in the Davis LOOP2 packet, it’s not in the 
LOOP packet or archive record (the defaults) from the console. So unless 
you have set WeeWX to use the LOOP2 packet WeeWX will never see windchill 
from the console, irrespective of StdWXCalculate settings.

Gary
---

And the User's Guide states "Not all stations support LOOP2 data. You need 
firmware version 1.90 or later."

So I don't think the loop_hilo parameter will affect the windchill value 
with my setup.


On Saturday, December 31, 2022 at 1:07:01 PM UTC-5 jo...@johnkline.com 
wrote:

> Tom and friends will know for sure, but I believe the low you are seeing 
> (at 07:31) is from the archive_day_windchill table.
>
> You likely have the following in your weewx.conf
> # Whether to include LOOP data in hi/low statistics
> loop_hilo = True
>
> This tells weewx (well, it tells it to do exactly what the comment says). 
>  Note: vantage loop packets do indeed include windchill.
>
> The archive table (produced from vantage archive records) does not include 
> this low and the graphs are produced from archive records.
>
> I don’t think you are seeing anything *wrong*.
>
> Note: these highs and lows in the daily stats get wiped out if you run 
> wee_database —rebuild-daily (which is unfortunate).
>
> On Dec 31, 2022, at 9:21 AM, Steve Schindler  wrote:
>
> During the recent cold weather, I noticed a discrepancy between the 
> windchill minimum value in the table and the value/time shown on the graph. 
> For 12-24-22, the Low Wind Chill in the Since Midnight table is 23.6F at 
> 07:31, but the graph doesn't reflect that value. It shows a low of about 
> 27F at about 8:00. For 12-25-22, the temperature discrepancy is about the 
> same but time difference is greater. See the screenshots below. All other 
> values (temp, humidity, wind) agree between the table and the graphs.
>
>
>
> I'm using a Davis VP2 with firmware version 1.82 so WeeWX is calculating 
> the windchill value. 
>
> Any thoughts on what's happening and how it can be corrected?
>
> I'm in Florida so my troubleshooting/testing opportunities are limited to 
> when a cold front passes through. However, I suspect that heat index has 
> the same problem and, if so, I'll have plenty of time to work on that that 
> this summer. :-)
>
> 12-24
>
> 
>
>
> 12-25
>
> 
>
> -- 
> You received this message because you are subscribed to the Google Groups 
> "weewx-user" group.
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> https://groups.google.com/d/msgid/weewx-user/183e065c-2fc6-4b2b-aaff-99ec35fa8ca1n%40googlegroups.com
>  
> 
> .
>
>
> 
>
> 
>
>

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Re: [weewx-user] Windchill Test Value / Graph Discrepancy

['John Kline' via weewx-user]

Tom and friends will know for sure, but I believe the low you are seeing (at 07:31) is from the archive_day_windchill table.You likely have the following in your weewx.conf    # Whether to include LOOP data in hi/low statistics    loop_hilo = TrueThis tells weewx (well, it tells it to do exactly what the comment says).  Note: vantage loop packets do indeed include windchill.The archive table (produced from vantage archive records) does not include this low and the graphs are produced from archive records.I don’t think you are seeing anything *wrong*.Note: these highs and lows in the daily stats get wiped out if you run wee_database —rebuild-daily (which is unfortunate).On Dec 31, 2022, at 9:21 AM, Steve Schindler  wrote:During the recent cold weather, I noticed a discrepancy between the windchill minimum value in the table and the value/time shown on the graph. For 12-24-22, the
Low Wind Chill in the Since Midnight table is 23.6F at 07:31, but the
graph doesn't reflect that value. It shows a low of about 27F at
about 8:00. For 12-25-22, the temperature discrepancy is about the same
but time difference is greater. See the screenshots below. All other values (temp, humidity, wind) agree between the table and the graphs.
I'm using a Davis VP2 with firmware version 1.82 so WeeWX is
calculating the windchill value. Any thoughts on what's happening and how it can be corrected?
I'm in Florida so my troubleshooting/testing opportunities are limited to when a cold front passes through. However, I suspect that heat index has the same
problem and, if so, I'll have plenty of time to work on that that this summer.
:-)12-2412-25



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Re: [weewx-user] Windchill vs Heat Index vs Feel like

[Barry]

Thanks for the comments, time to go and learn about Met and Python :-)

Barry

On Monday, May 16, 2022 at 11:40:11 a.m. UTC-4 peterq...@gmail.com wrote:

> Calculations are here: 
> https://github.com/weewx/weewx/blob/6c90a174f9cf81b1b93b83b70a426199a51b47ba/bin/weewx/wxformulas.py
>
> see the comment:
>The 'new' algorithm uses: 
> https://www.wpc.ncep.noaa.gov/html/heatindex_equation.shtml
>
>
>
>
>
> On Mon, May 16, 2022 at 8:18 AM Greg Troxel  wrote:
>
>>
>> Barry  writes:
>>
>> > Now that I have (with help from the group) Weefx and the tempest 
>> running 
>> > well I would lie to throw out a Met.
>> >
>> > Current observation
>> >
>> > Wind  210/3knts
>> > Humidity75%
>> > Temp   20.1C
>> > Dewpoint15.5C
>> >
>> > Wind Chill 20.1C
>> > Heat Index20.1C  
>> > Feels Like  21.5C
>> >
>> > From what I have read Heat index is calculated from Temperature and 
>> > Humidity and Feels Like is calculated from Temperature, Humidity and 
>> Wind. 
>> > with any  wind,  would it not  decrease the Feel Like below the value 
>> of 
>> > the Heat Index? I am not sure how the Feel Like can be higher than the 
>> Heat 
>> > Index. Are Wind Chill, Heat Index and Feels like calculated by the 
>> Tempest, 
>> > weewx or a combination of both?
>>
>> There are a number of terms, and it woudl not shock me if some equipment
>> used a term with a non-standard definition.  The first thing you should
>> do is chase down what the words actually mean.  Often heat index type
>> values are relative to 50% humidity.  There's no reason to expect that
>> Heat Index and Feels Like have the same baseline treatment of humidity,
>> unless you read both definitions.
>>
>> I have never seen a definition for "Feels Like".  It seems to be an
>> acurite concept, basically heat index or wind chill, depending on
>> whether it is hot or cold, in some vague way.  I would not be surprised
>> if there were a number of inconsistent definitions.  I generally ignore
>> things like this, that aren't clearly traceable to a widely-agreed-on
>> definition backed up by the literature.
>>
>> Weewx can use values from hardware or calculate.  Read your weewx.conf
>> and look at the StdWXCalculate section, and read the docs about that.
>>
>> https://en.wikipedia.org/wiki/Heat_index
>>
>> There is also THSW, which I gather is popular in .au, but I am unclear
>> on it.
>>
>> -- 
>> You received this message because you are subscribed to the Google Groups 
>> "weewx-user" group.
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>> email to weewx-user+...@googlegroups.com.
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>> https://groups.google.com/d/msgid/weewx-user/rmio7zxzetg.fsf%40s1.lexort.com
>> .
>>
>
>
> -- 
> Peter Quinn
> (415)794-2264 <(415)%20794-2264>
>

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Re: [weewx-user] Windchill vs Heat Index vs Feel like

[p q]

Calculations are here:
https://github.com/weewx/weewx/blob/6c90a174f9cf81b1b93b83b70a426199a51b47ba/bin/weewx/wxformulas.py

see the comment:
   The 'new' algorithm uses:
https://www.wpc.ncep.noaa.gov/html/heatindex_equation.shtml





On Mon, May 16, 2022 at 8:18 AM Greg Troxel  wrote:

>
> Barry  writes:
>
> > Now that I have (with help from the group) Weefx and the tempest running
> > well I would lie to throw out a Met.
> >
> > Current observation
> >
> > Wind  210/3knts
> > Humidity75%
> > Temp   20.1C
> > Dewpoint15.5C
> >
> > Wind Chill 20.1C
> > Heat Index20.1C
> > Feels Like  21.5C
> >
> > From what I have read Heat index is calculated from Temperature and
> > Humidity and Feels Like is calculated from Temperature, Humidity and
> Wind.
> > with any  wind,  would it not  decrease the Feel Like below the value of
> > the Heat Index? I am not sure how the Feel Like can be higher than the
> Heat
> > Index. Are Wind Chill, Heat Index and Feels like calculated by the
> Tempest,
> > weewx or a combination of both?
>
> There are a number of terms, and it woudl not shock me if some equipment
> used a term with a non-standard definition.  The first thing you should
> do is chase down what the words actually mean.  Often heat index type
> values are relative to 50% humidity.  There's no reason to expect that
> Heat Index and Feels Like have the same baseline treatment of humidity,
> unless you read both definitions.
>
> I have never seen a definition for "Feels Like".  It seems to be an
> acurite concept, basically heat index or wind chill, depending on
> whether it is hot or cold, in some vague way.  I would not be surprised
> if there were a number of inconsistent definitions.  I generally ignore
> things like this, that aren't clearly traceable to a widely-agreed-on
> definition backed up by the literature.
>
> Weewx can use values from hardware or calculate.  Read your weewx.conf
> and look at the StdWXCalculate section, and read the docs about that.
>
> https://en.wikipedia.org/wiki/Heat_index
>
> There is also THSW, which I gather is popular in .au, but I am unclear
> on it.
>
> --
> You received this message because you are subscribed to the Google Groups
> "weewx-user" group.
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> .
>


-- 
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(415)794-2264

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Re: [weewx-user] Windchill vs Heat Index vs Feel like

[Greg Troxel]

Barry  writes:

> Now that I have (with help from the group) Weefx and the tempest running 
> well I would lie to throw out a Met.
>
> Current observation
>
> Wind  210/3knts
> Humidity75%
> Temp   20.1C
> Dewpoint15.5C
>
> Wind Chill 20.1C
> Heat Index20.1C  
> Feels Like  21.5C
>
> From what I have read Heat index is calculated from Temperature and 
> Humidity and Feels Like is calculated from Temperature, Humidity and Wind. 
> with any  wind,  would it not  decrease the Feel Like below the value of 
> the Heat Index? I am not sure how the Feel Like can be higher than the Heat 
> Index. Are Wind Chill, Heat Index and Feels like calculated by the Tempest, 
> weewx or a combination of both?

There are a number of terms, and it woudl not shock me if some equipment
used a term with a non-standard definition.  The first thing you should
do is chase down what the words actually mean.  Often heat index type
values are relative to 50% humidity.  There's no reason to expect that
Heat Index and Feels Like have the same baseline treatment of humidity,
unless you read both definitions.

I have never seen a definition for "Feels Like".  It seems to be an
acurite concept, basically heat index or wind chill, depending on
whether it is hot or cold, in some vague way.  I would not be surprised
if there were a number of inconsistent definitions.  I generally ignore
things like this, that aren't clearly traceable to a widely-agreed-on
definition backed up by the literature.

Weewx can use values from hardware or calculate.  Read your weewx.conf
and look at the StdWXCalculate section, and read the docs about that.

https://en.wikipedia.org/wiki/Heat_index

There is also THSW, which I gather is popular in .au, but I am unclear
on it.

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[weewx-user] Windchill vs Heat Index vs Feel like

[Barry]

Now that I have (with help from the group) Weefx and the tempest running 
well I would lie to throw out a Met.

Current observation

Wind  210/3knts
Humidity75%
Temp   20.1C
Dewpoint15.5C

Wind Chill 20.1C
Heat Index20.1C  
Feels Like  21.5C

>From what I have read Heat index is calculated from Temperature and 
Humidity and Feels Like is calculated from Temperature, Humidity and Wind. 
with any  wind,  would it not  decrease the Feel Like below the value of 
the Heat Index? I am not sure how the Feel Like can be higher than the Heat 
Index. Are Wind Chill, Heat Index and Feels like calculated by the Tempest, 
weewx or a combination of both?

Barry



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[weewx-user] Windchill stored as heatindex

[Hyrules Hyrules]

I have been reading about heat index and looking at the NOAA formula to 
calculate the heatindex but it seems there is something wrong in the 
archive table as it stores the heatindex as the windchill value. Is this a 
bug ? I'm using a vantage pro 2 and MySQL to store data. Thanks.

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Re: [weewx-user] Windchill generated wrong when using WMR89 and not getting outdoor temp readings

[Thomas Keffer]

In general, when emitting a value, WeeWX defers to the hardware. After all,
that's why you own it. Occasionally, the hardware is wrong, and that seems
to be the case for you.

One option is to set up [StdQC] to filter out the "bonker" values.

Or, let the software calculate the values.

Or, replace the hardware with something more reliable.

-tk

On Sat, Sep 15, 2018 at 5:50 AM T  wrote:

> Hi,
>
> I've noticed a thing when setting up my WMR89. I've found the
> "Windchill generated wrong." thread from december 2017 but I don't see
> any conclusive solution there, just a suggestion to switch to software
> windchill, and then a suggestion there might be a bug in the WMR200
> driver.
>
> On my WMR89, when I had archive_interval=60, I'd often get N/A values
> for temperature etc. in weewx. I've solved that, thanks to help in the
> "Problems reading values from WMR-89" thread.
>
> When getting those temperature N/A values, I also got -89C as
> windchill value. Looking at the verbose output from the WMR89 that I
> attached to a message in the "Problems reading values from WMR-89"
> thread, I see LOOP packets with a windchill value of
> -128.22 (which converts to -89 Celsius).
>
> So I guess that's what the WMR89 is sending if it hasn't received any
> values from the outdoor temp/humidity sensor. Weird, but OK, we have
> to deal with it.
>
> What's the recommended way of dealing with this? Are there recommended
> settings for windchill and other parameters under [StdWXCalculate]?
> Perhaps not specifically for WMR89 but in general? Right now it's
> windchill=prefer_hardware, the obvious solution seem to be to set it
> to windchill=software (although I'd like a
> windchill=prefer_hardware_but_use_software_if_hardware_value_is_bonkers
> setting). One message in the "Windchill generated wrong." thread
> thinks setting windchill=software isn't an optimal solution ("masking
> the issue rather than fixing it").
>
> Any thoughts?
>
> Thanks,
>
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[weewx-user] Windchill generated wrong when using WMR89 and not getting outdoor temp readings

[T]

Hi,

I've noticed a thing when setting up my WMR89. I've found the
"Windchill generated wrong." thread from december 2017 but I don't see
any conclusive solution there, just a suggestion to switch to software
windchill, and then a suggestion there might be a bug in the WMR200
driver.

On my WMR89, when I had archive_interval=60, I'd often get N/A values
for temperature etc. in weewx. I've solved that, thanks to help in the
"Problems reading values from WMR-89" thread.

When getting those temperature N/A values, I also got -89C as
windchill value. Looking at the verbose output from the WMR89 that I
attached to a message in the "Problems reading values from WMR-89"
thread, I see LOOP packets with a windchill value of
-128.22 (which converts to -89 Celsius).

So I guess that's what the WMR89 is sending if it hasn't received any
values from the outdoor temp/humidity sensor. Weird, but OK, we have
to deal with it.

What's the recommended way of dealing with this? Are there recommended
settings for windchill and other parameters under [StdWXCalculate]?
Perhaps not specifically for WMR89 but in general? Right now it's
windchill=prefer_hardware, the obvious solution seem to be to set it
to windchill=software (although I'd like a
windchill=prefer_hardware_but_use_software_if_hardware_value_is_bonkers
setting). One message in the "Windchill generated wrong." thread
thinks setting windchill=software isn't an optimal solution ("masking
the issue rather than fixing it").

Any thoughts?

Thanks,

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[weewx-user] Windchill

[Kalli]

Hallo

bei mir ist der Windchill gleich wie die Aussentemperatur.

normal muss der Windchill doch andere werte liefern.

mfg. Kalli

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[weewx-user] Windchill generated wrong.

[gjr80]

Also, what type of station?

Gary

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[weewx-user] Windchill generated wrong.

[gjr80]

Not doubting your transcription but would be good to see the actual LOOP packet 
or REC record that gave the nonsense result.

Gary

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[weewx-user] Windchill generated wrong.

[Mark Jenks]

Yes, I live somewhere where the air hurts my face..  But that being said, 
when windchill hits -25, it calculates it wrong.

Outside Temperature -9.4°F
Wind Chill -24.6°F
Heat Index -9.4°F
Dewpoint -34.2°F
Humidity 27%
Barometer 30.507 inHg
Barometer Trend (3 hours) 0.038 inHg
Wind 8 mph from 288° (WNW)
Rain Rate 0.00 in/hr
Inside Temperature 62.2°F
Inside Humidity 26%


Outside Temperature -9.4°F
Wind Chill 641.2°F
Heat Index -9.4°F
Dewpoint -34.2°F
Humidity 27%
Barometer 30.507 inHg
Barometer Trend (3 hours) 0.038 inHg
Wind 8 mph from 270° (W)
Rain Rate 0.00 in/hr
Inside Temperature 62.2°F
Inside Humidity 26%

Here is the dump of data right before the bad calculation.

Dec 26 00:20:15 server weewxd: LOOP:   2017-12-26 00:19:33 CST (1514269173) 
altimeter: None, appTemp: None, barometer: None, cloudbase: None, dateTime: 
1514269173, dewpoint: None, heatindex: None, hourRain: 0.0, humidex: None, 
inDewpoint: None, maxSolarRad: None, pressure: None, rain: 0.0, rain24: 
0.0, rainRate: 0.0, rainTotal: 1.778, usUnits: 1, windchill: None, windDir: 
None, windGustDir: None
Dec 26 00:20:15 server weewxd: LOOP:   2017-12-26 00:19:33 CST (1514269173) 
altimeter: None, appTemp: None, barometer: None, cloudbase: None, dateTime: 
1514269173, dewpoint: None, heatindex: None, humidex: None, inDewpoint: 
26.9311557969, inHeatindex: None, inHumidity: 26, inTemp: 62.24, 
maxSolarRad: None, pressure: None, rainRate: 0, usUnits: 1, windchill: 
None, windDir: None, windGustDir: None
Dec 26 00:20:15 server weewxd: LOOP:   2017-12-26 00:19:33 CST (1514269173) 
altimeter: None, appTemp: None, barometer: None, cloudbase: None, dateTime: 
1514269173, dewpoint: None, heatindex: None, humidex: None, inDewpoint: 
None, maxSolarRad: None, pressure: None, rainRate: 0, usUnits: 1, 
windchill: -24.0, windDir: 270.0, windGust: None, windGustDir: None, 
windSpeed: 8.05299066698
Dec 26 00:20:15 server weewxd: LOOP:   2017-12-26 00:19:41 CST (1514269181) 
altimeter: None, appTemp: None, barometer: None, cloudbase: None, dateTime: 
1514269181, dewpoint: None, heatindex: None, humidex: None, inDewpoint: 
None, maxSolarRad: None, pressure: None, rainRate: 0, usUnits: 1, 
windchill: -24.0, windDir: 270.0, windGust: None, windGustDir: None, 
windSpeed: 8.05299066698
Dec 26 00:20:15 server weewxd: LOOP:   2017-12-26 00:19:41 CST (1514269181) 
altimeter: None, appTemp: None, barometer: None, cloudbase: 6459.19655848, 
dateTime: 1514269181, dewpoint: -34.1684648573, heatindex: -9.4, humidex: 
-9.4, inDewpoint: None, maxSolarRad: None, outHumidity: 27, outTemp: -9.4, 
pressure: None, rainRate: 0, usUnits: 1, windchill: None, windDir: None, 
windGustDir: None
Dec 26 00:20:15 server weewxd: LOOP:   2017-12-26 00:19:43 CST (1514269183) 
altimeter: None, appTemp: None, barometer: None, cloudbase: None, dateTime: 
1514269183, dewpoint: None, heatindex: None, humidex: None, inDewpoint: 
26.9311557969, inHeatindex: None, inHumidity: 26, inTemp: 62.24, 
maxSolarRad: None, pressure: None, rainRate: 0, usUnits: 1, windchill: 
None, windDir: None, windGustDir: None
Dec 26 00:20:15 server weewxd: LOOP:   2017-12-26 00:19:47 CST (1514269187) 
altimeter: None, appTemp: None, barometer: None, cloudbase: None, dateTime: 
1514269187, dewpoint: None, heatindex: None, humidex: None, inDewpoint: 
None, maxSolarRad: None, pressure: None, rainRate: 0, usUnits: 1, 
windchill: -25.0, windDir: 270.0, windGust: 8.05299066698, windSpeed: 
8.05299066698
Dec 26 00:20:15 server weewxd: LOOP:   2017-12-26 00:19:53 CST (1514269193) 
altimeter: None, appTemp: None, barometer: None, cloudbase: None, dateTime: 
1514269193, dewpoint: None, heatindex: None, humidex: None, inDewpoint: 
26.9311557969, inHeatindex: None, inHumidity: 26, inTemp: 62.24, 
maxSolarRad: None, pressure: None, rainRate: 0, usUnits: 1, windchill: 
None, windDir: None, windGustDir: None
Dec 26 00:20:15 server weewxd: LOOP:   2017-12-26 00:20:01 CST (1514269201) 
altimeter: None, appTemp: None, barometer: None, cloudbase: None, dateTime: 
1514269201, dewpoint: None, heatindex: None, humidex: None, inDewpoint: 
None, maxSolarRad: None, pressure: None, rainRate: 0, usUnits: 1, 
windchill: -24.0, windDir: 315.0, windGust: None, windGustDir: None, 
windSpeed: 8.05299066698
Dec 26 00:20:15 server weewxd: LOOP:   2017-12-26 00:20:13 CST (1514269213) 
altimeter: None, appTemp: None, barometer: None, cloudbase: None, dateTime: 
1514269213, dewpoint: None, heatindex: None, humidex: None, inDewpoint: 
26.9311557969, inHeatindex: None, inHumidity: 26, inTemp: 62.24, 
maxSolarRad: None, pressure: None, rainRate: 0, usUnits: 1, windchill: 
None, windDir: None, windGustDir: None
Dec 26 00:20:15 server weewxd: LOOP:   2017-12-26 00:20:15 CST (1514269215) 
altimeter: None, appTemp: None, barometer: None, cloudbase: None, dateTime: 
1514269215, dewpoint: None, heatindex: None, humidex: None, inDewpoint: 
None, maxSolarRad: None, pressure: None, rainRate: 0, usUnits: 1, 
windchill: -24.0, windDir: 270.0, windGust: 7.82929648179, wind