Cumulus Support

Hi all

Can anybody tell me how Cumulus predicts the weather forecast, because since I have had it hooked up to my WH1081 it has got the weather forecast constantly wrong and does not even match the weather stations predictions which in most cases have been right. An example being right now it is snowing outside temperature at about 1'C yet Cumulus is saying it is Settled & Fine, which is the same prediction I get most days although it sometimes does change to exceptionally fine & settled every now and then.

Other than that Cumulus is working great.

Oh I have an update, since I posted the last message the forecast has now changed to Exceptional weather, Settled Fine.

It's still snowing outside.

Have you modified the settings on Cumulus' station page for the forecast? (lower right hand corner)
Defaults are: min. 950, max. 1050 hPa (mb).
And are they the same units as your setting for pressure?

Your banner suggests that your pressure reading is way too high, which probably accounts for the poor performance of the forecast. How did you calibrate it?

Have you modified the settings on Cumulus' station page for the forecast? (lower right hand corner)
Defaults are: min. 950, max. 1050 hPa (mb).
And are they the same units as your setting for pressure?

The settings are has you have discribed and the pressure settings are both set to hPa on Cumulus and the weather station.

Your banner suggests that your pressure reading is way too high, which probably accounts for the poor performance of the forecast. How did you calibrate it?

I thought there was something wrong with the pressure readings has I have another weather station (not a very sofisticated unit but it as always got the predictions right) which gives me a more realistic pressure reading and the difference between the two was always quite high.

Has for calibration I have not calibrated it, it is just displaying the readings that the station has been sending it since I turned it on three weeks ago.

Do you think it is a calibration error and I need to adjust it to match the other weather station I have, or is there a specific way to calibrate the sensors.

Daggers wrote:Has for calibration I have not calibrated it, it is just displaying the readings that the station has been sending it since I turned it on three weeks ago.

Do you think it is a calibration error and I need to adjust it to match the other weather station I have, or is there a specific way to calibrate the sensors.

Yes, it's crucial that you calibrate it, otherwise your readings are meaningless. The manual tells you how to do it - see the bit about setting the relative pressure, under the 'Pressure' section. It should really make it clear how important this is and why you need to do it. If you're reasonably confident about the reading on your other device, you can set the relative pressure to the same as that.

I have had exactly the same issue and have taken the following steps, could someone confirm that I have got it right please

- Checked absolute pressure reading on receiver
- Compared it with relative pressure reading on receiver
- Calculated the difference
- Subtracted the difference in the Cumulus Calibration screen

Many thanks


Mark

markwall06 wrote:I have had exactly the same issue and have taken the following steps, could someone confirm that I have got it right please

No, I'm afraid not - you shouldn't need to use the Cumulus calibration at all. You need to set the relative pressure on your station so that's reading the correct sea-level pressure, as compared with a known good source not too far from you, and preferably at a time of stable pressure.

markwall06 wrote:I have had exactly the same issue and have taken the following steps, could someone confirm that I have got it right please

Hi Mark

As Steve says, best to calibrate your console rather than Cumulus.

Page 10 or the manual, step 3 talks about setting the relative pressure. You will need to try and locate a local alternative source to compare readings. Can't help with any suggestions as you have no location in your profile. Try to ensure pressure is stable (i.e. not increasing or decreasing at the time).

Manual is here if needed - http://wiki.sandaysoft.com/index.php?ti ... set_manual

PS - Can you also adjust your profile in the control panel and change your station from 'Maplin' to 'FineOffset' as it will make more sense.

thanks

Daj: Been following this topic, looking at the manuals I have and searching these archives, but you finally made it start making sense... the calibration steps are to make sure the console is set to Relative (as opposed to Absolute, using "Pressure" "Step 1") ), and then change the pressure value to one you think is the more correct (using "Pressure" "Step 3") . Am I correct in these steps?

On the PWS weather site I see a Davis station about 10 miles away reporting their pressure closer to what the NOAA website reports (closest NOAA station is 40 miles away) than what I show, so I may use this station's reading as my reference.

Thanks for pointing me in the correct direction!
--
Roger
KJ4AJP
http://kj4ajp.mambm.com/weather/

Thanks for the replies guys I will have ago at this later when I get home.

Guys

I think I'm moving in the right direction but would appreciate it if you could just hold my hand through this

Ok so I got my pressure from here
http://weather.lgfl.org.uk/console.aspx

Adjusted my console so the reading is identical

Removed the calibration adjustment within Cumulus

AND

My barometer reading in Cumulus has now shot up to 1024 and my forecast shown as settled fine. (It's not!)

Surely that Cumulus barometer reading should be the same as on my console?

Am I doing something obviously wrong?

Thanks

Mark

You did restart Cumulus after changing the pressure settings on your station?

Steve

Cheers - that was the obvious thing I did wrong


Mark