That would explain that, then So.... not anything that can be done about it, Ken?
Well, I've taken a look and experimented with Ranier's great cloud-height.php script and regarding the 'jumping' as it refreshes most every time, there's not much that can be done except to remove the <span class="ajax" id="ajaxcloudheightimg">...</span> from around the invocation of the script (in other words, don't AJAX refresh it).
The AJAX and the image use wind direction/speed to determine if a new image is needed, so in variable winds, you can get a refresh each time the AJAX kicks in. So...
Just use the dashboard to load a static image (created at the time the page is reloaded by the browser), and your display won't 'jump'. The downside (of course) is that unless you force a reload of the page every 5 minutes or so, the image can become 'out of sync' with the current conditions -- I think this is a small price to pay for getting a stable display
BTW, the wind-rose doesn't normally 'jump' because it is a set of 16 static images that the browser can cache, and the thermometer only updates when there is a 1 degree change to the current (or high/low).
Hope this helps...