CPU Temperature with / without Protective Case

I've been measuring the temperatures on my 2011 MBP 13" / 8GB all day with various workloads. Surprisingly, the plastic case does not seem to have affected the temperature much one way or another.

Do any of these temperatures seem abnormal? I am afraid I don't really know what temperature range my computer "ought" to be within.

WITH CASE / WITHOUT CASE
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CPU=110-146 F / CPU=115-173 F
FAN=1994-2003 RPM / FAN=1992-2001RPM


The workload varied across the day. I took five readings for each one. The higher temperature readings resulted from times when I was working the computer hardest (email, itunes playing music, microsoft word, excel, voodoopad, chrome, bookends, and adobe acrobat combining multiple files into a single pdf).

There is nothing particularly rigorous about the test conditions. I wasn't doing exactly the same work in exactly the same location, and by the end of the day (without the case) the computer was running a little warmer because it had been in use (the highest readings for each were taken within 30 minutes of one another). Obviously, I am not really pushing the computer as much as some users might (this is the most load I would ever put on the computer in a regular workday). I imagine hardcore gamers / programmers / video editors would see different results.

I was a bit surprised by the results. I was expecting the case to have caused the computer to run noticeably warmer. I was thinking about getting a keyboard cover (the moshi one). Has anyone noticed their computer running much hotter with it on?

 

Thanks. Does anyone happen to know what the range of "normal" operating temperatures are for the 2011 MBP 13" base model?

 

Thanks!