Weather Underground

[William Grimsley]

Hi there,

I just noticed this little problem on the Weather Underground weather station IDEVONEX12:

Cumulus.jpg

Weather Underground.jpg

The high wind gust today's are different. On Weather Underground, the high wind gust today is 25.7 km/h which is 16 mph. On Cumulus, the high wind gust today is 15 mph which is correct.

[RayProudfoot]

If the Cumulus value is correct then you need to raise a ticket with WU if you feel that a 1mph difference is worth reporting. I noticed the same 1mph difference for 1 Feb too.

My own records match so it might be down to your Vue setup. Has this been a problem for a while?

[William Grimsley]

If the Cumulus value is correct then you need to raise a ticket with WU if you feel that a 1mph difference is worth reporting. I noticed the same 1mph difference for 1 Feb too.

My own records match so it might be down to your Vue setup. Has this been a problem for a while?

Well, the high wind gust today was recorded on Weather Underground before Cumulus. So, I'm wondering if the high wind gust today was carried over from yesterday on Weather Underground? The difference on 01/02/2014 was correct by me in Cumulus. Hmmm, it might be. I asked a few days ago how to check?

[Karv]

25.7km/h = 15.97mph

I think all you are seeing here is a rounding issue between the various different types of software, and really, 1mph, accept it already, how may more posts about 1mph ????

If it was 10 mph, fine, but please please nor more posts about 1 mph wind difference!

Stop please!

[William Grimsley]

25.7km/h = 15.97mph

I think all you are seeing here is a rounding issue between the various different types of software, and really, 1mph, accept it already, how may more posts about 1mph ????

If it was 10 mph, fine, but please please nor more posts about 1 mph wind difference!

Stop please!

Can't be. When I have a 15 mph average wind speed it shows 24.1 km/h. But, this is 25.7 km/h which is 16 mph, ok? Fine. But, you don't see BBC Weather showing 16 mph if it's 15 mph.

[RayProudfoot]

William,

I appreciate it may frustrate you but as Karv suggested it's almost certainly due to rounding. I also see slight anomalies in pressure on the RapidFire feature but it doesn't worry me. I suggest you ignore it.

[William Grimsley]

I suggest you ignore it.

Ok, I may aswell seen as I can't do anything about it on Weather Underground.

This might help what I'm trying to explain:

Wind.jpg

[steve]

I'm going to regret getting involved in this, but in this case it's obvious what the 'problem' is:

2014-02-02 00:00:00,43.2,39.8,29.50,SW,232,10.0,16.0,88,0.01,,,0.00,Cumulus v1.9.4,2014-02-02 00:00:00,
2014-02-02 00:05:00,43.0,39.7,29.50,SW,228,9.0,16.0,88,0.01,,,0.00,Cumulus v1.9.4,2014-02-02 00:05:00,

The 16 mph wind reading clearly occurred just before midnight. The 'recent max gust' figure was still 16 for those first uploads to WU after midnight. End of thread, hopefully.

Have Davis not got back to you with that copy of Weatherlink yet?

[William Grimsley]

The 16 mph wind reading clearly occurred just before midnight. The 'recent max gust' figure was still 16 for those first uploads to WU after midnight. End of thread, hopefully.

Have Davis not got back to you with that copy of Weatherlink yet?

Ok, I understand.

No, they haven't.

[William Grimsley]

I think I've got it now. So, if the high wind gust today is lower than the wind gust at 00:00. Then, Weather Underground doesn't record it as the high wind gust? So, when the high wind gust today is recorded higher than before. Then, Weather Underground and Cumulus will match?

[William Grimsley]

There we go. The high wind gust today is the same on Weather Underground and Cumulus.

[Karv]

Can't be. When I have a 15 mph average wind speed it shows 24.1 km/h. But, this is 25.7 km/h which is 16 mph, ok? Fine. But, you don't see BBC Weather showing 16 mph if it's 15 mph.

A short maths tutorial for your benefit.

To convert km/h to Mph, divide by 1.609344

25.7 divided by 1.609344 = 15.96923964049948 which, as you are so particular about precision, you will see is clearly not 16 mph.

A rounded value would be 16mph.

This is where rounding in software comes into play.

additionally for the record, 24.1km/h = 14.97504573291975 which is also not 15mph.

Regards
K

[William Grimsley]

Can't be. When I have a 15 mph average wind speed it shows 24.1 km/h. But, this is 25.7 km/h which is 16 mph, ok? Fine. But, you don't see BBC Weather showing 16 mph if it's 15 mph.

A short maths tutorial for your benefit.

To convert km/h to Mph, divide by 1.609344

25.7 divided by 1.609344 = 15.96923964049948 which, as you are so particular about precision, you will see is clearly not 16 mph.

A rounded value would be 16mph.

This is where rounding in software comes into play.

additionally for the record, 24.1km/h = 14.97504573291975 which is also not 15mph.

Regards
K

Ok.

1) I don't need a maths lesson I am in 2nd to top set in Maths.

2) Weather Underground rounds every wind value to the nearest integer.