Cumulus Support

I have just started using the Cumulus software, this week, previously using FreeWX for my WM-918 Weather Station. So far, I think the Cumulus software is excellent and the reason I switched to it was because of the more frequent RapidFire functionality it provides to www.wunderground.com, which FreeWX lacked.

However, I believe there may be a a problem with the resetting of the dailyrainCM value that is being sent to www.wunderground.com, via the Cumulus software.

In my Cumulus software, I had the Log Rollover Time set to 9am. What I noticed, as per the www.wunderground.com log snippet below, was that rain that started falling during the afternoon of 2009-02-16, which resulted in 13mm (1.3cm) of rain, was still being sent through in the dailyrainCM field, until 10:00am on 2009-02-17:

2009-02-17 09:52:00,15.6,10.0,1020.9,ESE,116,11.3,20.9,68,0.0,,,1.3,Cumulus v1.8.5,
2009-02-17 09:57:00,15.9,10.0,1020.9,ESE,116,9.7,19.3,67,0.0,,,1.3,Cumulus v1.8.5,
2009-02-17 10:02:00,16.1,10.0,1020.9,SE,124,9.7,16.1,66,0.0,,,0.0,Cumulus v1.8.5,
2009-02-17 10:07:00,16.4,10.0,1020.9,ESE,118,9.7,16.1,66,0.0,,,0.0,Cumulus v1.8.5,
2009-02-17 10:12:00,16.6,10.0,1020.9,SE,125,9.7,16.1,64,0.0,,,0.0,Cumulus v1.8.5,

What has happened, is that the www.wunderground.com site has added another 13mm to the monthly total, as well as showing that 13mm fell on 2009-02-17, even though there was no rain on 2009-02-17.

Shouldn't the dailyrainCM value be reset at midnight, in the data that is sent to www.wunderground.com, as this site uses the midnight -> midnight period, for its reporting? Is the Cumulus software resetting the dailyrainCM value, based on the Log Rollover Time value? Is the reason that the Cumulus software is resetting the dailyrainCM value at 10:00am, due to New Zealand currently using Daylight Savings time and the Cumulus software is not taking this into consideration?

In the meantime, I have changed the Log Rollover Time to midnight, to see if this will make a difference. But, based on my observations, I believe that the Cumulus software may reset the dailyrainCM values at 1:00am.

Any information would be much appreciated.

Thanks



Gregg

Gregg,

You've spotted my deliberate mistake

Cumulus just sends the current daily total rainfall to Wunderground; it only maintains one daily total and it's based on the chosen start of day. So, if you use the 0900 start of day option, it's the rain since 0900 that gets sent. It hadn't occurred to me that this would cause problems at Wunderground.

Setting the rollover time to midnight will get around the problem; Cumulus will reset the value at midnight, not 0100. It resets at 1000 in summer on the 0900 setting because it does take daylight savings into account. In the UK, the rollover time is 0900 GMT all year round, so it's 1000 BST in summer. I had assumed that any other country which used the 0900 start of day would also do this, as it makes sense to me. But this assumption is clearly wrong. I need to add an option to keep the 0900 rollover time the same all year round according to the local clock.

As I'm doing a few small changes anyway, it shouldn't be too hard to add this option. Fixing the Wunderground problem will be a bit harder; I'll see what I can do.

Steve

Thanks Steve.


Gregg

I've added the option to keep the 0900 start to the same clock time year round. I'll upload it later when I've had chance to test it a bit.

The Wunderground change is huge. The most complicated thing in Cumulus, by a wide margin, is trying to get today's rainfall total correct. I will have to duplicate all of that code to allow for a 'since midnight' total in addition to the existing 'since start of meteorological day'. Unless I can think of some clever way of doing it differently with the data I already have. I think I will have to say that I don't propose to do this change in the current version, unless I have a rare moment of inspiration and think of an easy way to do it. I'll make sure Cumulus 2 doesn't have this deficiency.

Perhaps they could just fix Wunderground so that it caters for those of us who don't use midnight as the start of our day

Steve

steve wrote:Setting the rollover time to midnight will get around the problem; Cumulus will reset the value at midnight, not 0100.

Thanks Steve, changing the rollover time to midnight, fixed the problem.




Gregg

I've added an option to the latest build (733) to give the choice of sticking to clock time year-round for the 0900 option. Not that it helps anyway, if you need to use midnight anyway to get around the Wunderground issue.

Steve

I've now put in some changes to calculate a 'since midnight' rain total even when an 0900 day start is in use. I'll test it a bit myself first, rain is forecast overnight, but I won't be able to test all possibilities, so I'll be relying on everyone to try it out. It will potentially affect everyone, even those with a midnight day start, because it's simpler to use the same (new) variable for everyone.

Steve

The 'rain since midnight' code seems to be working, with the limited testing I can do easily, so I've uploaded a new build (746) with it in.

Steve