It is possible that this page will report a problem where no problem exists. If you believe that this has happened, then please contact me (address at the bottom of this page) and explain clearly why you think this page is in error. Note that any changes that you make may take a few days to show up here, so please give it a week before commenting.
Location Map: If this message persists, then your browser is not compatible with Google Maps.
| |
Larger Smaller Google Earth. | |
The site location should be at the mark shown -- or very close. Clicking within the map area (or you can drag the 'KGVL' marker) will display the latitude/longitude of that point.
For issues with data quality, please contact the ASOS Operations Center.If the displayed location (or elevation) of the weather observing location is incorrect, please drag the marker to the right location (or click in the right location), and then send the updated information. Please note that we are trying to spot either the Stevenson Screen (or equivalent) or the location where the barometric readings are taken.
Can you help with location quality? Please indicate if the marker on the map points at the weather instrument cluster:
The location information for this site was gathered from 13 data sources. The source which most closely matches the consensus is chosen. Many of these sources only report the location to the nearest minute (or hundredth of degree). This can lead to the marker being placed noticeably incorrectly. Please see Discussion of Location Errors for more information. Show location history.
Latitude: dummy (deg min sec), dummy (decimal), dummy (LORAN)
Longitude: dummy (deg min sec), dummy (decimal), dummy (LORAN)
Estimated elevation is dummy metres (dummy feet) from dummy.
Location is dummy (reverse geocoded).
Move marker to new address.
The station (or view from the station) is shown here. You can choose the view direction to see the surroundings. Other information (and somewhat larger images) can be found by clicking on the picture.
You can try to find photographs from the area surrounding the site marker by clicking on Find nearby photographs. (There are some) (There are none) (There may be some) (Automatically loaded if any)
Recent observations from this weather station can be downloaded as a CSV file suitable for importing into various spreadsheet programs: last 7 days, last 14 days, last 28 days, last 56 days. This data can also be linked directly from Excel using a Web Query. The main link goes to the page with the data on it, and the IQY link is the Web Query that will access it: last 7 days (IQY: last 7 days), last 14 days (IQY: last 14 days), last 28 days (IQY: last 28 days), last 56 days (IQY: last 56 days).
All the means and standard deviations shown below are from the last 91 days. Change analysis period to Last 3 days Last 7 days Last 14 days Last 4 weeks Last 8 weeks Last 26 weeks Last 39 weeks Last 52 weeks
By default, the longer analysis periods display graphs that show the long term performance of this station. The graphs show the mean error over time, and include error bars which are one standard deviation long. This provides an easy way to see if there are any underlying trends in the data. Note that a 'step' in your data does not (necessarily) mean that something happened to your station. It could mean that another station came online in the local area, and they are changing the analysis.
The analysis is performed by MADIS. This web page just provides visualization of the data that MADIS produces. There are a number of very knowledgeable people who participate on the WXQC Mailing List who do understand exactly how MADIS works and can resolve issues when the analysis seems to be broken. However, in most cases, the station readings are at fault, or the software that is transmitting the data to CWOP. Please check those paths first.
You can also see how this station compares with other stations.
|
|
These values are within range, so your sensor is probably calibrated correctly.
NOTE: If the error above is POSITIVE, then it means that the analysis temperature is HIGHER than the reported temperature. This means that your sensor is reading COLDER than expected. |
|
These values are within the acceptable range. This probably means that your sensor is sited correctly and is calibrated correctly.
NOTE: If the error above is POSITIVE, then it means that the analysis humidity is HIGHER than the reported humidity. This means that your sensor is reading DRYER than expected. | QC only available for Dewpoint. |
The wind vector is the average wind over the relevant period. Note that if the wind blows North for half the time at 2 knots, and then blows South for the other half of the time at 2 knots, then the result is zero -- i.e. North wind and South wind will cancel out. Over time, the direction of the wind and of the analysis should match pretty well. If the lengths of the vector are different, then it could mean either that your anemometer reads high or low, or that you are in a more shielded or more open space. |
|
Today | Last 7 days | |
---|---|---|
You can look at those for comparison purposes. The average difference between your station and each station below is listed as well. This may allow you to detect local stations which are erroneous. You can also use these numbers to adjust your instruments -- especially if a number of ASOS stations have similar differences to your station. Also, try increasing the analysis period to more than the default 28 days. The difference is only given if both stations report reasonably often during each day. Some stations only report every 6 hours, and this makes the average of less interest. In this case, the average is not displayed. The values reported are the differences between this station and the neighboring station. I.e. if the difference is positive, then this station is reading higher than the neighboring station.
You can also subscribe to an RSS feed to tell you when new stations come online in this area. Choose either within 100 miles or 250 miles . For stations covered by your Forecast Office: Atlanta (FFC) .
Site | Distance | Location | Barometer | Temperature | Dewpoint | ||
---|---|---|---|---|---|---|---|
GW3550 | 11.9 miles | South | HOSCHTON, GA, US (lat 34.1025°, long -83.8628°, altitude 312 metres) | 0.5mb | 2.6°F | -2.5°F | |
GW0101 | 13.5 miles | Southwest | Buford, GA, US (lat 34.0947°, long -83.9308°, altitude 371 metres) | -0.8mb | 0.1°F | -2.8°F | |
FW7198 | 15.4 miles | Southeast | Jefferson, GA, US (lat 34.1088°, long -83.6472°, altitude 256 metres) | 0.6mb | 4.3°F | -2.9°F | |
EW3780 | 15.4 miles | South | Dacula, GA, US (lat 34.0628°, long -83.9242°, altitude 349 metres) | 0.9mb | 0.7°F | -2.2°F | |
EW7107 | 22.4 miles | West | Cumming, GA, US (lat 34.2048°, long -84.2132°, altitude 336 metres) | 1.1mb | 2.2°F | -1.9°F | |
GW4221 | 23.0 miles | Southwest | LAWRENCEVILLE, GA, US (lat 33.9885°, long -84.0393°, altitude 330 metres) | 1.0mb | 3.1°F | -1.0°F | |
EW5460 | 23.7 miles | Southwest | Alpharetta, GA, US (lat 34.1247°, long -84.2045°, altitude 320 metres) | -0.1mb | 3.5°F | -2.6°F | |
FW7257 | 23.8 miles | Southwest | Lawrenceville, GA, US (lat 33.9827°, long -84.0558°, altitude 304 metres) | -0.2mb | 1.9°F | -2.2°F | |
EW6934 | 24.2 miles | Northeast | Cornelia, GA, US (lat 34.5183°, long -83.5297°, altitude 460 metres) | 0.4mb | 1.8°F | -0.3°F | |
FW041425.4 miles | Northwest | | Dahlonega, GA, US (lat 34.5217°, long -84.1565°, altitude 487 metres)
| 0.8mb | 4.4°F | 0.9°F
| |
The sites marked above thus did not report continuously during the analysis period, so the offsets may (probably will) not be accurate.
The 'MADIS rating' reports on the percentage of observations that pass the MADIS checks. You should aim for two thumbs up!
Degrees Minutes Seconds: VWS/VWSAPRS, WeatherLink 5.5, WeatherLink (5.2-5.4), WeatherView (Linux)
Decimal degrees: FreeWX, WeatherView32 (PC application)
LORAN: WeatherDisplay, WUHU, Henriksen WServer
CWOP Siting Guide (PDF): This is a guide to siting and operating a CWOP station. This is a must-read document.
Another CWOP Guide (PDF): This is another guide to siting and operating a CWOP station. This is a must-read document.
Urban Siting and Operations (PDF): This is a guide to siting and operating a CWOP station in an urban environment.
APRS WX Message format: This describes the actual format of the messages transmitted that carry WX information.
WXQC Mailing List: This is a mailing list where data quality issues are discussed. Assistance with software configuration can often be found here.
Topo Map Reading Guide: How to read USGS topographic maps, with a good section on reading contours.
Geographically nearby web pages: Use Geourl to find web pages that deal with locations geographically close to this site.