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' >>>> >>>> >>>> >>>> -- You received this message because you are subscribed to the Google Groups "weewx-user" group. 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