Am I missing something, or isn't it pretty clear that Berkely has bandwidth capacity limitations Monday - Friday which will impact all S@H users. On the weekends, the problem is dramatically less, so all the queues catch up on their uploads, as well as their downloads.
Wait, theory #2: A majority of S@H machines crunch Mon-Fri, so there are more machines trying to connect during that period.
If the weather reports continue on a daily basis, I would expect to see the Results start from 0 on Mondays, and rise throughout the week, and then drop off again on Sat/Sun. Keep the reports coming, please.