Wind graph speed wobbles?

Can anybody explain to me why these 2 screenshots of the wind graph - taken 2 minutes apart - are so different? :?

Screen shot 1;

Screen shot 2;

I think it is down to the resolution of the graph. As there is a lot of data to be shown in that 12 hour period the wind peaks and troughs will change from minute to minute, but data is not lost, just that all data cannot be shown in a confined scale - I think Brian says that if only the last 6 hours are shown on the graph this does not occur.

It happens to my graphs too.

yes, thats it
it will show half the data, and then the next minute, show the other half the data (for a 12 hour graph)
your custom screen banner is looking great bristolwx!

Excellent - thanks. Its good to know that my eyes aren’t playing tricks on me. 8O