FAQ

The Cumulus FAQ

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Installing and Running Cumulus

What operating systems does Cumulus run on?

Windows XP, Windows Server 2003, Windows Vista, Windows 7, Windows Home Server, and Windows Server 2008. It may also work on Windows 2000, but this is not supported. You will probably not be able to get it to work on Windows 2000 with a Fine Offset station.

What weather stations does Cumulus work with?

Davis Vantage Pro (VP) and Vantage Pro2 (VP2), Oregon Scientific WM918, WMR918, WMR928 and WMR968, stations which use the Easyweather software such as MyDEL, Nevada, Watson and Fine Offset, with model numbers such as WH1080, WH1081, W8681, 265NC etc, and the La Crosse WS2300 range. You may have problems with corrupt data if you use a WS23xx with a serial/USB adapter; this combination is therefore not supported.

For a complete list see the Supported Devices page.

Will you support weather station X?

It’s quite hard to support a particular weather station when I don’t have access to one. Also, most companies don’t seem to like third parties writing software for their stations, so don’t make the protocol available. However, if the protocol is available somewhere, and you are prepared to do all of the testing (it will be frustrating, hard work), I may consider adding support for your weather station. Please post a request on the forum. Bear in mind that I develop and support Cumulus in my spare time and I am already very busy with Cumulus, so I may not be able to fit in the required work. I certainly can't commit to any time frames.

How do I upgrade to a new release?

Back up your data, and run the new setup. Occasionally, there may be actions you need to perform before or after the upgrade - these will be documented in the readme.txt file.

How do I back up my data, or transfer it to Cumulus on another computer?

Copy the contents of the Cumulus ‘data’ folder. If moving to another computer, you may also want to consider copying your cumulus.ini file, so you keep your settings - you may need to 'tweak' a few things (serial port number etc). If you have any files that you have created or modified yourself - a strings.ini file and/or a twitter.txt file, for example, you may want to copy those over too, along with any customised web pages. This article in the wiki gives more details above moving Cumulus: Moving cumulus

What are the formats of the Cumulus data files?

These are detailed in the Log Files section of this Wiki and also in the Cumulus help file, in the section “Data log file format”

What do the various wind speeds in Cumulus correspond to, with Fine Offset stations?

For Fine Offset stations, the ‘latest’ value in Cumulus corresponds to the ‘gust’ value on the station. The ‘gust’ value in Cumulus is the highest of the ‘latest’ figures in the last 10 minutes. The ‘average’ value in Cumulus is either the ’speed’ (just called 'wind' on the console) from the station (a 48-second average, apparently) or, if you have Cumulus set to calculate a 10-minute average, it’s the average over the last 10 minutes of the ‘latest’ values. If you also have 'use speed for avg calculation' set, then the Cumulus-calculated average is the average over the last 10 minutes of the 48-second 'speed' values supplied by the station.

How do I make Cumulus run automatically when Windows starts?

There is no option in Cumulus to set this up automatically as I prefer to leave it under the control of the user: The safest and most reliable method is simply to put a shortcut in your Startup folder. If you are running Vista or Windows 7, you may find that Cumulus gets blocked by UAC if you try to run it from the Startup folder, in which case it is recommended that you use Task Scheduler instead. See here for a good description of how to do this - http://blogs.techrepublic.com.com/window-on-windows/?p=616

How does Cumulus handle Daylight Saving Time?

As far as the timestamps in the logs (and the graphs) are concerned, Cumulus doesn't do anything in particular for DST. It generates timestamps based on the Windows clock. So basically, at the start of DST (i.e. when the clocks 'go forward') you will get an apparent gap of one hour in your data, and similarly at the end of DST (i.e. when the clocks 'go back') you will get an apparent hour of duplicate timestamps in your logs and graphs. The exact timing of the affected hours depends on the type of station and when Cumulus was running.

What formula does Cumulus use for Apparent Temperature?

It uses a formula from the Australian BOM - http://www.bom.gov.au/info/thermal_stress/#atapproximation

How does Cumulus know the height of the cloud base?

It doesn't. It uses a calculation which gives the theoretical height above ground level at which Cumulus clouds might form, based on the current temperature and dew point. It assumes that the difference between temperature and dew point decreases by about 4.4 degrees Fahrenheit per 1000 feet increase in altitude. When the two values coincide, the air is saturated (relative humidity = 100%) and Cumulus clouds may form.

How is my rain rate calculated?

For stations which supply a rain rate, Cumulus uses that. For stations which don't supply a rain rate (e.g. Fine Offset and La Crosse), Cumulus simply takes the rain total from the last five minutes and calculates a rate based on that; e.g. 0.3mm in 5 minutes is a rate of 3.6mm/hr.

Where does Cumulus get its monthly and annual rainfall totals from?

It adds up the corresponding daily totals in dayfile.txt. If your monthly and/or annual totals are incorrect, then you need to correct the daily totals which make up those figures, with Cumulus stopped.

How do I reset all my data to start again from scratch?

Stop Cumulus and delete the contents of the data folder.

I don't have a solar sensor. How do I remove the solar data from the supplied web pages?

Locate the Cumulus 'web' folder on your PC and edit the following files:

indexT.htm

Remove the following code:

<tr class="td_temperature_data">
     <td>Solar Radiation</td>
     <td><#SolarRad>&nbsp;W/m&sup2;</td>
     <td>Evapotranspiration Today</td>
     <td><#ET>&nbsp;<#rainunit></td>
</tr>

todayT.htm and yesterdayT.htm

Remove the following code:

<tr class="td_temperature_data">
     <td>Hours&nbsp;of&nbsp;Sunshine</td>
     <td><#SunshineHours></td>
     <td>&nbsp;</td>
</tr>

Troubleshooting

My 'Error' light is flashing

Click on it, and a window will open describing the error. It may just be a temporary ftp problem.

I’ve configured my ftp details but the web pages aren’t appearing on my site

Try setting ‘use active FTP mode’.

I’ve tried active FTP mode, buy my web pages (or my realtime.txt file) still don’t appear?

Are you absolutely sure you have set the ftp path correctly? Most problems like this are a result of an incorrect path. Try turning on the ftp logging and look in the ftplog.txt and realtimeftplog.txt files. It is best to supply a relative path - i.e. with no leading 'slash'. Please don't ask me what path you need to supply, it is impossible for me to guess how your web space is set up. If you cannot work it out, ask your web space provider for help.

My web pages have things like <#location> in them

You’ve edited them with something like Dreamweaver, and it’s changed the angle brackets on the Webtags to "& lt ;" and "& gt ;" - you need to change them back to < and >. These may look very similar on your screen, but you can only generate the correct ones by using the appropriate keys on your keyboard.

My ‘new record’ light has stopped flashing

The ‘new record’ light only flashes when an all-time record has been broken. It stops flashing if you click on it or restart Cumulus, until another all-time record is broken.

I installed a new version and my web page templates got over-written

The supplied web page templates are part of Cumulus and will be over-written on upgrade. If you want to create your own web pages, don’t edit the supplied ones, use the ‘extra files’ facility. From version 1.8.9, the installer offers the option of not over-writing the web templates; it unconditionally also installs them to a sub-folder of the web folder called 'originals', so you can refer to them if required, even if you chose not to over-write those in the web folder.

I can’t find my data files!

You’re probably running Windows Vista or Windows 7 (or one of the corresponding server versions of Windows). Look in C:\Users\[username]\AppData\Local\VirtualStore\Program Files\Cumulus - note that this is a 'hidden' folder. Ideally, to avoid this situation, you would install to somewhere outside the Program Files hierarchy, as recommended in the readme.txt.

My sunrise and sunset times are wrong

You've almost certainly entered your co-ordinates incorrectly. Make sure to use a 'W' for your longitude if you're West of the Greenwich meridian. One other less likely possibility is that you have set the wrong time zone on your PC.

The Moon rise or set time is showing dashes.

The moon doesn’t rise and set every day, the dashes appear when that event doesn’t occur on that particular day. The period between a moon rise and set is approximately 12 hours and 25 minutes, on average. The moon rises (or sets) approximately 50 minutes later, on average, each day. It therefore follows that sometimes the moon will not rise or set on a particular day - i.e. it had risen the previous day, or will set on the following day.

I’ve ‘zoomed’ a graph, how do I get it back to full size?

Drag from lower right to upper left.

My monthly and/or annual rainfall totals are wrong

The monthly and annual rainfall totals are calculated from the daily totals in Dayfile.txt. So you need to stop Cumulus and edit the daily totals until your monthly and annual totals are correct. The format of the dayfile.txt file is in the help file, in the section “Data log file format”, or here. If you need to, you can specify a year-to-date total to add in for the period up to the point where you started using Cumulus, so that your first year’s total is correct. This is on the Station Configuration screen.

The ‘gust’ line has disappeared from my graph

You probably have Cumulus set to calculate a 10-minute average, and your logger period is 10 minutes or longer, so your gust comes out the same as the average when using data from the logger.

My ‘gust’ values are the same as my ‘average’ wind speed values.

As above, you probably have Cumulus set to calculate a 10-minute average, and your logger period is 10 minutes or longer, so your gust comes out the same as the average when using data from the logger.

I’ve just installed Cumulus, and it didn’t download all the old data from my weather station

Cumulus deliberately doesn’t attempt to download any data from before the point when you first run it. If you wish, although this isn't recommended, you can force it to download data from any point by editing the ‘Timestamp’ line in the today.ini file (in the data folder), before starting it (you will need to have run it at least once previously). If you do this, you will probably need to edit your data files as you may have duplicate entries and/or entries out of order. Your rain totals will almost certainly also be wrong - the total for "today" in particular. See the FAQ entry about correcting rainfall data.

Cumulus doesn’t show the same pressure as my Fine Offset console

First of all, check that you are comparing the Cumulus display with the ‘relative’ pressure on your console. Cumulus displays pressure corrected to sea level, which the console calls ‘relative pressure’.

If your relative pressure still disagrees with the Cumulus display, it may be due to the following: The Fine Offset stations only supply absolute/station pressure to Cumulus, so it has to adjust to sea level. When Cumulus starts, it reads the pressure ‘offset’ (the difference between absolute/station and relative/sea level pressure) from the station so it can use it subsequently to calculate the sea level pressure. Sometimes the offset that is read is clearly garbage, so Cumulus uses zero as a best effort.

To circumvent this, you can edit cumulus.ini, and in the [Station] section add an entry:

EWpressureoffset=x.y

where x.y is your pressure offset. Cumulus will then use this instead of reading it from the station.

My pressure suddenly dropped! Or suddenly increased!

If you have a Fine Offset station, and this happened when you started Cumulus, see: "Cumulus doesn’t show the same pressure as my Fine Offset console" above

I get an error when I try to view my all-time records. Also, they don’t appear on my web site

The date format on your system has probably changed. Look at the Startdate line in cumulus.ini and check whether this is in the correct format for your system. If not, stop Cumulus and correct the date format.

I get an error when I close Cumulus

Cumulus does sometimes report an error when you close it. This does not appear to cause any problems, you can just close the error message. I don't seem to be able to do anything about this, as the 'crash' is not in code that I have control over. You may be able to avoid this error by avoiding closing Cumulus while it is uploading to the internet. Please don't bother sending me a bug report about this.

I'm using the supplied web pages, and get lower case in places where I want upper case

It's in the CSS. Edit stylesheet.css and find lines like: "text-transform: lowercase;" and remove them.

My forecast says "Not available"

You can get Cumulus to create a simple forecast by selecting 'Cumulus Forecast' on the Stations Settings screen.

My forecast always says "Exceptional Weather, Stormy, much precipitation"

You probably have incorrect Pressure Extreme settings. Make sure that the values you have supplied match the units you have selected for the extremes. Note that the units for the extremes are not related to the units you have chosen for pressure display in Cumulus. The option of supplying mb/hPa or inHg for the extremes is merely a convenience; you can supply either, but the values and the units must of course match.

My computer hibernated/suspended, and I lost data/my graphs 'flat-lined'

Cumulus can't cope with being suspended, it just carries on as normal after being woken. There is an option in the station settings to 'close on suspend', so Cumulus will close itself as a safety measure, if you forget to do it manually. Don't use the 'close on suspend' option and the 'confirm shutdown' option at the same time; this will cause problems.

But I strongly recommend that you don't have your computer set to go into any form of standby while Cumulus is running - it's continuously gathering real-time data, after all, so it's a rather strange thing to do.

My heat index/humidex/wind chill is the same as my temperature

Wind chill only applies when the wind speed is above 4.8 kph and the temperature is below 10C. (The temperature cutoff is an option in Cumulus, but should really always be set). Heat index only applies when the temperature is above 27C and the humidity is above 40%.

The rest of the time they are the same as the ambient temperature.

While Humidex does not have any 'cutoff' values, at low temperature and/or humidity it will give the same figure as ambient temperature.

My station invented some rain that didn't really occur, and I want to set it to zero

Cumulus calculates rainfall from a counter supplied by the station which keeps increasing as the rain causes the rain gauge to tip. Cumulus remembers the value of that counter at the start of the meteorological day, so that at any time duing the day it can calculate today's rain by subtracting that figure from the current value of the counter. The start of day figure is stored in today.ini as the "Start=" figure, and the current value of the counter is stored in the monthly log files (e.g. jan10log.txt) as the 'total rainfall counter'. See the Log Files section of this Wiki for the formats of the files.

So, to set today's total to zero, stop Cumulus and look for the current value of the total rainfall counter on the last line of the current monthly log file, and set the Start= figure in the today.ini file to that value. Don't just set the Start figure to zero, that will give you a large total for today! You can set today's total to other values in a similar way; just set the Start= figure so that the difference between that and the current total rainfall counter is the total you want to achieve. You may also want to edit the "Total rainfall today so far" values for today in the monthly log file to correspond.

Example:
My Start figure is 43.2 (ignore any superfluous digits; round to an appropriate number of decimal places)

[Rain]
High=0
HTime=09:00
Start=43.2000007629395
Yesterday=0.400001525878906

On the last line of my jan10log.txt file, my 'total rainfall counter' is 49.4, and hence my 'total rainfall today so far' is 6.2.

19/01/10,17:20,6.8,89,5.1,25.4,35.2,159,0.0,6.2,1020.56,49.4,23.8,44,30.8,1.6,6.8

However, I know that it hasn't actually rained, and that 'rain' was caused by wind rocking the rain gauge, or electrical interference, or whatever. So, to set today's rain to zero, I set the Start figure equal to the total rainfall counter. (Another way of looking at it is: to remove the 6.2 units of rain, I add 6.2 to the Start figure):

[Rain]
High=0
HTime=09:00
Start=49.4
Yesterday=0.400001525878906

and I set the total rain so far today to zero:

19/01/10,17:20,6.8,89,5.1,25.4,35.2,159,0.0,0.0,1020.56,49.4,23.8,44,30.8,1.6,6.8

Note that I don't edit the 'total rainfall counter', it would achieve nothing, it's simply a record of the actual counter in the hardware. I would probably also edit all of the other entries for today in jan10log.txt to set their total rainfall today so far values to zero.

If the erroneous rainfall didn't occur today, you just need to edit the total for the relevant day in dayfile.txt (and optionally edit the entries in the monthly log file). If it was yesterday, you can also optionally edit yesterday's total in today.ini.

Cumulus is showing a different wind speed compared to my console

You're probably comparing gusts and average speeds. If you have a Fine Offset station, see #What_do_the_various_wind_speeds_in_Cumulus_correspond_to.2C_with_Fine_Offset_stations.3F

Note that you can't compare the graphs drawn by Easyweather and Cumulus unless you are certain that they are plotting the same data. They can't both be running at the same time, so one would normally be plotting 'live' data at a given interval, and the other will be plotting data downloaded from the station's logger. The wind speed will hence not normally be the same for a particular time on the graph as it may well have changed at the point that it is saved to the logger. The only situation where it would be valid to compare the graphs would be if neither were running at the times you are comparing, and both subsequently downloaded the same data from the logger.

I get error -32710 with Cumulus and my USB Davis station

The USB support in the Davis DLL which Cumulus uses doesn't seem to work. You need to use the CP210X USB/serial software which Davis supply, and use the station in serial mode. If you have previously been using your station with Weatherlink in USB mode, you will need to change to serial mode in Weatherlink before you can use the station with Cumulus. You can do this using this utility from Davis.

When I start Cumulus, the graphs restart again each time and don't show the earlier data

You probably have an error in one or more data files. Look near the beginning of the latest file in the Diags folder for an error message which will tell you which file is in error and which line is causing the problem. It may simply be a blank line. Edit the file with Cumulus stopped. Note that you may need to repeat this process; only the first error is shown.

My Davis station shows a higher maximum wind speed than Cumulus

The Davis DLL which Cumulus uses to read data from the station can sometimes miss readings. You can try to minimise the effect of this by editing cumulus.ini (with Cumulus stopped) and add a line to the [Station] section, thus:

VP2SleepInterval=0

This sets the interval between reads to zero (the default is 500 ms).

Cumulus won't read the data from my station

If you have one of the Fine Offset clones, make sure you have configured your relative pressure correctly. If Cumulus finds an 'impossible' value, it will ignore all data from your station.

The peak values on my graphs are not the same as my extreme values

The graphs are snapshots of the data, taken once a minute while Cumulus is running. If the extreme value did not coincide exactly with the point at which the data was added to the graph, then it will not appear on the graph. This is most noticeable with wind gusts, the value of which can change rapidly, even over a period of a minute.

My extreme values do not appear in the 'monthly' data logs

The data logs are snapshots of the data, taken at the configured interval while Cumulus is running (or at the station's configured interval when data is read from the station's logger). If the extreme value did not coincide exactly with the point at which the data was logged, then it will not appear in the log. This is most noticeable with wind gusts, the value of which can change rapidly between log entries.

Cumulus takes a long time to download the data from my Davis station at start up

When Cumulus starts, it asks the station for all the data from the logger since the last time it was running. If the timestamp that it supplies does not exactly match the timestamp of an entry in the Davis logger, the station has a strange 'feature' where it decides to send the entire contents of the logger. This will take some time to download, during which the Davis console display will appear freeze.

It is recommended that you set the logging interval in Cumulus to the same interval as the station, then Cumulus will be able to make sure it uses a timestamp that matches an entry in the logger.

Today is the shortest/longest day, but Cumulus says that tomorrow will be a few seconds shorter/longer

The routines I use to calculate the length of the day aren't really suitable for this level of accuracy.

Cumulus got the forecast wrong!

Cumulus uses a forecast based on the Zambretti Forecaster (see Google). Note that this is a 'forecast' for the following 12 hours or so; it is not a 'nowcast' (what the weather is doing now). Please regard the forecast as 'for entertainment purposes only'. Do not base any decisions on it, and bear in mind that it is a very simple calculation based on only a few basic parameters. Some people get reasonable results, others do not. You can try tweaking the pressure extreme settings, but don't expect the forecast to be as good as that provided by the agencies which have invested millions in their forecasting systems.

I only see one set of points on the wind direction graph

This always happens just after you restart Cumulus, as there is only one set of data available to be plotted.

My graphs appear to be plotted less frequently just after Cumulus starts up

When running live, Cumulus plots data at 1-minute intervals. When it starts up, it pre-fills the graphs with data from the log files, which generally (depending on how you have Cumulus and your station configured) will be at less frequent intervals.

I closed Cumulus, the 'please wait' form appeared, but Cumulus didn't close, even after several minutes

If you've closed Cumulus shortly after it has downloaded a lot of data from the logger, it can take a while for the logging thread to get everything written away to disk, and Cumulus won't close until this has completed. However, in some circumstances, there seems to be a situation where Cumulus will never close, so you will need to close it with task manager. If you think you know what conditions cause this to happen, please let me know.

Cumulus isn't logging data at the interval that I set

It logs data at the interval you have configured, while it is running. If there is data to read from the station logger at start up, each logger entry is logged to the Cumulus log files, so those entries will be at the logger interval that you have configured in your station.

Cumulus 1.9.1 takes a very long time to shut down

You may have closed it very soon after starting it up, when it had a lot of data to download from the station logger, and you use Weather Underground. Version 1.9.1 has a new facility where it 'catches up' with data that hasn't been uploaded to Weather Underground while it hasn't been running. This takes a little while, and if you close it while it is doing it, it will take a long time for all of the updates to time out. You need to give it sufficient time to finish the upload, but unfortunately there is no indication that the upload is taking place.

In the next version, there will be an indicator to show that the 'catch up' is taking place; the 'catch up' will be optional'; and it will abort much more quickly if you still close it while the catch up is taking place.

Website

How do I replace the 'bird' image on the website

There are several ways to change the image of the 'bird' on the standard Cumulus web page. You will need an FTP tool

• The simplest way is to upload a new picture to the images folder of your website; the file should be called picture.jpg. Please ensure the images not too large and bear in mind it will appear on the bottom left of the page; the site data may cover some of the image. As a guide, the default image is 600 x 450 pixels.
• Secondly, you may upload an image using your own file name. Edit the weather.css file and look for the line background-image: url(images/picture.jpg); around line 9 and adjust as necessary. Upload the edited css file to the website
• if you wish to remove the image completely edit the weather.css file and remove the line background-image: url(images/picture.jpg); Upload the css file to to the website

How do I change the "Welcome to." on the front page

The Welcome message is controlled within Cumulus. Click on the Station Configuration within Cumulus and Edit the Name field within the Location section. The Description field is also used on the front page of the site.