Thanks

On Friday, August 22, 2025 at 8:22:25 AM UTC-4 [email protected] wrote:

> EDIT: Sorry. I meant to say station pressure calculator not station 
> elevation calculator
> You can use this station pressure calculator: 
> https://www.sensorsone.com/elevation-station-qfe-sea-level-qnh-pressure-calculator/?ab=1&v0=1865&f0=ft&f1=inHg0C&f2=inHg0C
>
> Note: This calculator uses aviation terms. QFE = station pressure and QNH 
> = altimeter setting. I've already entered in your elevation. All you have 
> to do is enter in the altimeter setting of your airport in the QNH input 
> field and the calculator will calculate your QFE (station pressure).
> ---
>
> On Thursday, August 21, 2025 at 2:49:01 PM UTC-4 [email protected] wrote:
>
>> Given:
>>
>> Aug 20 6:35 pm
>>
>> Altitude (true) = 1865 ft
>> WeeWX altitude = 70 ft
>> WeeWX altimeter= 29.86 inHg (rounded))
>> WeeWX barometer = 29.85 inHg (rounded)
>> WeeWX pressure = 29.78 inHg (rounded)
>>
>> NOTE: at altitude = 70 ft we are very close to sea level (altitude = 0). 
>> As mentioned in my previous post, all three pressures hypothetically, 
>> should be the same at sea level. We can see that clearly happening at the 
>> 70 ft altitude where the readings start getting closer together.
>>
>> Aug 20 18:35 (from mesowest):
>>
>> KPSK elevation = 2106 ft
>> KPSK pressure = 27.74
>> KPSK altimeter = 29.95
>>
>> EXAMPLE station elevation calculation:
>>
>> LaCrosse true altitude = 1865 ft
>> KPSK altimeter= 29.95 inHg
>>
>> Solving for LaCrosse "pressure" = 27.99 inHg
>>
>> As reported LaCrosse "pressure" = 29.78 inHg
>>
>> It looks like your current pressure of 29.78 is much too high.
>>
>> In order to calculate altimeter, at a location with a 1865 ft altitude, 
>> your relative pressure on your console should always be reading 1.96 Hg 
>> higher than your current live absolute pressure ("pressure"). 
>>
>> To re-calibrate your display console:
>>
>> 1. Calculate your station pressure (follow the example above) and then 
>> add 1.96 to this number to get your corrected relative pressure. Modify the 
>> existing relative pressure in your display console.
>> 2. Your pressure is wrong and you will have to fix it. I was unable to 
>> find a way to modify your absolute pressure from your manual. You may have 
>> to contact LaCrosse and see how this may be done.
>> 3. Alternatively, I believe there is a way to add a pressure calibration 
>> offset in the WeeWX config file.
>> 4. Once you fixed your absolute pressure and relative pressure,, 
>> don'forget to put back your correct station altitude of 1865 ft.
>> ---
>>
>> On Wednesday, August 20, 2025 at 7:11:02 PM UTC+4 kufuu wrote:
>>
>>> Correction , I have weewx set at 70ft elevation to try and match another 
>>> weather station, sorry about that.
>>>
>>>
>>> On Wednesday, August 20, 2025 at 6:50:00 PM UTC-4 kufuu wrote:
>>>
>>>> Im about 15 miles away
>>>>
>>>> On Wednesday, August 20, 2025 at 6:47:42 PM UTC-4 kufuu wrote:
>>>>
>>>>> My actual elevation is 1865ft , weewx is set to 0
>>>>>
>>>>> Using configuration file /etc/weewx/weewx.conf
>>>>> REC:    2025-08-20 18:35:00 EDT (1755729300) 'altimeter': 
>>>>> '29.856197863702114', 'appTemp': '84.16620032955495', 'barometer': 
>>>>> '29.850973617639387', 'cloudbase': '1750.7310847902036', 'dateTime': 
>>>>> '1755729300', 'dewpoint': '69.42478322692313', 'ET': 'None', 'heatindex': 
>>>>> '77.86800000000002', 'humidex': '91.66911741879971', 'inDewpoint': 
>>>>> '56.232061622715676', 'inHumidity': '56', 'inTemp': '72.86000000000001', 
>>>>> 'interval': '5', 'maxSolarRad': '192.36417227192797', 'outHumidity': 
>>>>> '78', 
>>>>> 'outTemp': '76.82000000000002', 'pressure': '29.778039395', 'rain': 
>>>>> '0.0', 
>>>>> 'rainRate': '0.0', 'usUnits': '1', 'windchill': '76.82000000000002', 
>>>>> 'windDir': 'None', 'windGust': '0.0', 'windGustDir': 'None', 'windrun': 
>>>>> '0.0', 'windSpeed': '0.0'
>>>>>
>>>>> LOOP:   2025-08-20 18:35:44 EDT (1755729344) 'altimeter': 
>>>>> '29.856197863702114', 'appTemp': '84.16620032955495', 'barometer': 
>>>>> '29.850973617639387', 'cloudbase': '1750.7310847902036', 'dateTime': 
>>>>> '1755729344', 'dewpoint': '69.42478322692313', 'ET': 'None', 'heatindex': 
>>>>> '77.86800000000002', 'humidex': '91.66911741879971', 'inDewpoint': 
>>>>> '56.232061622715676', 'inHumidity': '56', 'inTemp': '72.86000000000001', 
>>>>> 'inTempBatteryStatus': '0', 'maxSolarRad': '189.6877965534115', 
>>>>> 'outHumidity': '78', 'outTemp': '76.82000000000002', 
>>>>> 'outTempBatteryStatus': '0', 'pressure': '29.778039395', 'rain': 'None', 
>>>>> 'rainBatteryStatus': '0', 'rainRate': '0.0', 'rxCheckPercent': '100', 
>>>>> 'usUnits': '1', 'windBatteryStatus': '0', 'windchill': 
>>>>> '76.82000000000002', 
>>>>> 'windDir': 'None', 'windGust': '0.0', 'windGustDir': 'None', 'windrun': 
>>>>> 'None', 'windSpeed': '0.0'
>>>>>
>>>>> KPSK dublin VA
>>>>>
>>>>>
>>>>> *Current conditions at* Dublin / New River Valley (KPSK) *Lat: *
>>>>> 37.13°N*Lon: *80.68°W*Elev: *2106ft. 
>>>>>
>>>>> Mostly Cloudy
>>>>>
>>>>> 76°F
>>>>>
>>>>> 24°C
>>>>>
>>>>> *Humidity* 
>>>>> 76% 
>>>>> *Wind Speed* 
>>>>> E 7 mph 
>>>>> *Barometer* 
>>>>> 29.95 in 
>>>>> *Dewpoint* 
>>>>> 68°F (20°C) 
>>>>> *Visibility* 
>>>>> 10.00 mi 
>>>>> *Heat Index*
>>>>> 77°F (25°C) 
>>>>> *Last update* 
>>>>> 20 Aug 6:35 pm EDT 
>>>>>
>>>>> *More Information:*
>>>>>
>>>>> Local Forecast Office <https://www.weather.gov/rnk>More Local Wx 
>>>>> <http://forecast.weather.gov/obslocal.php?warnzone=VAZ013&local_place=2%20Miles%20N%20Dublin%20VA&zoneid=EDT&offset=14400>3
>>>>>  
>>>>> Day History <http://forecast.weather.gov/data/obhistory/KPSK.html>Hourly 
>>>>> Weather Forecast 
>>>>> <https://forecast.weather.gov/MapClick.php?lat=37.1333&lon=-80.6833&unit=0&lg=english&FcstType=graphical>
>>>>>
>>>>>
>>>>>
>>>>> On Wednesday, August 20, 2025 at 6:00:53 PM UTC-4 [email protected] 
>>>>> wrote:
>>>>>
>>>>>> The three pressures on your LOOP was "altimeter", "barometer" and 
>>>>>> "pressure".
>>>>>> If you set station altitude = 0 then you are telling your weather 
>>>>>> station's barometer that it is located at sea level.
>>>>>> Therefore all three pressures shouldl read the same.
>>>>>>
>>>>>> "pressure" is just your local atmospheric pressure at your location's 
>>>>>> altitude..
>>>>>> "altimeter" is a sea level pressure that factors in your altitude 
>>>>>> above sea level and "corrects" your local pressure (station pressure) 
>>>>>> and 
>>>>>> calculates an equivalent pressure at sea level.
>>>>>> "barometer" is also a sea level pressure except it factors in your 
>>>>>> station pressure "(pressure" in WeeWX) , local  temperature and humidity 
>>>>>> and "corrects" it to an equivalent pressure at sea level. 
>>>>>>
>>>>>> I took a quick look at your weather station's manual and it appears 
>>>>>> that your display console reads "relative pressure" only. So in your 
>>>>>> case 
>>>>>> if you set station altitude = 0 in WeeWX, WeeWX's SLP correction will 
>>>>>> calculate a correction = 0. It makes sense because you told WeeWX you 
>>>>>> are 
>>>>>> located at sea level so there is no need to correct your "pressure" to 
>>>>>> sea 
>>>>>> level - you are already at sea level! Therefore "pressure" = "barometer" 
>>>>>> at 
>>>>>> sea level ( altitude = 0).
>>>>>>
>>>>>> I am not familiar with LaCrosse barometer operations- but I'll try to 
>>>>>> help. Other LaCrosse owners can certainly jump in... 
>>>>>>
>>>>>> Things to check.
>>>>>>
>>>>>> 1. What have you entered as your station altitude in WeeWX? Did you 
>>>>>> ensure that the station altitude you entered in WeeWX is the altitude of 
>>>>>> the barometric sensor (total height above sea level?) How did you 
>>>>>> calculate 
>>>>>> your station altitude?
>>>>>>
>>>>>> 2. Your weather station manual makes no mention of sea level pressure 
>>>>>> calculations, entering an altitude or elevation in your display 
>>>>>> console.or 
>>>>>> using an offset. The manual implies that the console only displays 
>>>>>> relative 
>>>>>> pressure?  Can you confirm that?
>>>>>>
>>>>>> 3. How close are you to an official weather station at an airport? 
>>>>>> Can you provide the ICAO code for it? Or the name of the airport?
>>>>>>
>>>>>> 4. Your July 31 LOOP altimeter and barometer readings appear to be 
>>>>>> unseasonably high for typical summertime weather. 
>>>>>>
>>>>>> 5. WeeWX is calculating altimeter correctly but WeeWX  barometer 
>>>>>> seems high compared to the Starpath online SLP calculator using the same 
>>>>>> input parameters. WeeWX "barometer" should be close to be the same or 
>>>>>> less 
>>>>>> than "altimeter" at the temperatures you reported.
>>>>>>
>>>>>> 6. Does your weather station use PC software from the manufacturer? 
>>>>>> If so, what is it reporting currently for absolute pressure and relative 
>>>>>> pressure? Can you adjust your absolute pressure?
>>>>>>
>>>>>> 7. Can you do another LOOP and give us the three pressures 
>>>>>> (altimeter, barometer, and pressure)?
>>>>>>
>>>>>> At the same time you do a LOOP ,can you obtain the altimeter setting 
>>>>>> of a close-by airport. And finally, can you obtain the elevation of that 
>>>>>> airport.
>>>>>>
>>>>>>  Summing up, we need: your station altitude, your weather station's 
>>>>>> absolute pressure, relative pressure and the current WeeWX LOOP pressure 
>>>>>> values (altimeter, barometer, and pressure) and the LOOP outside 
>>>>>> temperature. In order to make some pressure comparisons and accuracy 
>>>>>> checks. We would also need , the name(s) of any close-by airport(s) and 
>>>>>> how 
>>>>>> close you are to these airports. lus we need the airport altimeter 
>>>>>> setting 
>>>>>> reading and elevation. As Tom mentioned in the wiki, you have to be 
>>>>>> careful 
>>>>>> about comparing your relative pressure on your display console with the 
>>>>>> WeeWX "barometer" calculation. They could be two different things.
>>>>>>
>>>>>> Michael's advice is I think, correct. You probably need to 
>>>>>> re-calibrate or at least verify if your station pressure/absolute value 
>>>>>> is 
>>>>>> accurate.
>>>>>>
>>>>>> On Wednesday, August 20, 2025 at 1:33:38 AM UTC+4 [email protected] 
>>>>>> wrote:
>>>>>>
>>>>>>>
>>>>>>> Which obs_type "reads what is on the display", when altitude is set 
>>>>>>> to 0? pressure, altimeter or barometer or all three? (It should be all 
>>>>>>> three) When setting your altitude, pressure should always "read what is 
>>>>>>> on 
>>>>>>> the display", altimeter and barometer will change with the altitude you 
>>>>>>> configure.
>>>>>>>
>>>>>>> You should calibrate your station to the real pressure provided by a 
>>>>>>> reliable station near you, which is located at the same altitude. Then 
>>>>>>> configure the altitude of the station in weewx, then choose the 
>>>>>>> obs_types 
>>>>>>> you want to have displayed in your report. Depending on what you 
>>>>>>> choose, 
>>>>>>> the may or may not  "read what is on the display", which is perfectly 
>>>>>>> fine 
>>>>>>> for altimeter and barometer.
>>>>>>> kufuu schrieb am Dienstag, 19. August 2025 um 21:09:21 UTC+2:
>>>>>>>
>>>>>>>> If I put 0 altitude in weewx config then it reads what is on the 
>>>>>>>> display, is there any way to correct or just leave it 0 ? 
>>>>>>>>
>>>>>>>> On Thursday, July 31, 2025 at 9:29:40 AM UTC-4 kufuu wrote:
>>>>>>>>
>>>>>>>>> It can wait till then and good luck, 
>>>>>>>>>
>>>>>>>>> On Thursday, July 31, 2025 at 9:06:30 AM UTC-4 kufuu wrote:
>>>>>>>>>
>>>>>>>>>> Let me redo this and put the dates in order,
>>>>>>>>>> LOOP:   2025-07-31 08:45:20 EDT (1753965920) 'altimeter': 
>>>>>>>>>> '31.994965595814566', 'appTemp': '82.83203424777768', 'barometer': 
>>>>>>>>>> '31.942483641883886', 'cloudbase': '2805.6732703464695', 'dateTime': 
>>>>>>>>>> '1753965920', 'dewpoint': '70.70103761047554', 'ET': 'None', 
>>>>>>>>>> 'heatindex': 
>>>>>>>>>> '76.113', 'humidex': '90.81599237942409', 'inDewpoint': 
>>>>>>>>>> '55.52280883736111', 'inHumidity': '58', 'inTemp': '71.06', 
>>>>>>>>>> 'inTempBatteryStatus': '0', 'maxSolarRad': '357.687499228319', 
>>>>>>>>>> 'outHumidity': '87', 'outTemp': '74.84', 'outTempBatteryStatus': 
>>>>>>>>>> '0', 
>>>>>>>>>> 'pressure': '29.919783335', 'rain': '0.0', 'rainBatteryStatus': '0', 
>>>>>>>>>> 'rainRate': '0.0', 'rxCheckPercent': '100', 'usUnits': '1', 
>>>>>>>>>> 'windBatteryStatus': '0', 'windchill': '74.84', 'windDir': 'None', 
>>>>>>>>>> 'windGust': '0.0', 'windGustDir': 'None', 'windrun': 'None', 
>>>>>>>>>> 'windSpeed': 
>>>>>>>>>> '0.0'
>>>>>>>>>> REC:    2025-07-31 08:45:00 EDT (1753965900) 'altimeter': 
>>>>>>>>>> '31.994965595814566', 'appTemp': '82.83203424777768', 'barometer': 
>>>>>>>>>> '31.942483641883886', 'cloudbase': '2805.6732703464695', 'dateTime': 
>>>>>>>>>> '1753965900', 'dewpoint': '70.70103761047554', 'ET': 'None', 
>>>>>>>>>> 'heatindex': 
>>>>>>>>>> '76.113', 'humidex': '90.81599237942409', 'inDewpoint': 
>>>>>>>>>> '55.52280883736111', 'inHumidity': '58.0', 'inTemp': '71.06', 
>>>>>>>>>> 'inTempBatteryStatus': '0.0', 'interval': '5.0', 'maxSolarRad': 
>>>>>>>>>> '351.7781598061274', 'outHumidity': '87.0', 'outTemp': '74.84', 
>>>>>>>>>> 'outTempBatteryStatus': '0.0', 'pressure': '29.919783335', 'rain': 
>>>>>>>>>> '0.0', 
>>>>>>>>>> 'rainBatteryStatus': '0.0', 'rainRate': '0.0', 'rxCheckPercent': 
>>>>>>>>>> '97.5', 
>>>>>>>>>> 'usUnits': '1', 'windBatteryStatus': '0.0', 'windchill': '74.84', 
>>>>>>>>>> 'windDir': 'None', 'windGust': '0.0', 'windGustDir': 'None', 
>>>>>>>>>> 'windrun': 
>>>>>>>>>> '0.0', 'windSpeed': '0.0'
>>>>>>>>>> Traceback (most recent call last):
>>>>>>>>>>   File "/usr/share/weewx/weewx/reportengine.py", line 248, in run
>>>>>>>>>>     obj.start()
>>>>>>>>>>   File "/usr/share/weewx/weewx/reportengine.py", line 465, in 
>>>>>>>>>> start
>>>>>>>>>>     self.run()
>>>>>>>>>>   File "/usr/share/weewx/weewx/reportengine.py", line 621, in run
>>>>>>>>>>     ncopy += weeutil.weeutil.deep_copy_path(path, html_dest_dir)
>>>>>>>>>>   File "/usr/share/weewx/weeutil/weeutil.py", line 1811, in 
>>>>>>>>>> deep_copy_path
>>>>>>>>>>     shutil.copy(path, d)
>>>>>>>>>>   File "/usr/lib/python3.9/shutil.py", line 418, in copy
>>>>>>>>>>     copyfile(src, dst, follow_symlinks=follow_symlinks)
>>>>>>>>>>   File "/usr/lib/python3.9/shutil.py", line 264, in copyfile
>>>>>>>>>>     with open(src, 'rb') as fsrc, open(dst, 'wb') as fdst:
>>>>>>>>>> PermissionError: [Errno 13] Permission denied: 
>>>>>>>>>> '/var/www/html/weewx/seasons.css'
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>

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