I do recommend that folks using AJAX markup also continue to upload the page (with weather software tags) in order to allow folks who've turned off JavaScript to see your weather data anyway.
So, if you're using something like <span class="ajax" id="ajaxtemp">^vxv007^^uni007^</span>
to show the temperature, then you need to keep uploading the .htx so that VWS will replace the two weather tags with actual values. Then the AJAX will kick in (if JavaScript is enabled), and replace the area between the <span></span> with new text.
If JavaScript is turned off in the browser and you don't upload through VWS, then the viewer sees the current temperature as '^vxv007^^uni007^' .. not too helpful.
So.. if your page has weather tags, then you should continue to upload it regularly through the weather software so your website 'works' irrespective of the browser's JavaScript on/off status.
Best regards,
Ken