slightly hot e-30 (so far?)

[JHahn22@xxxxxxx]

Hello again everyone,
Lately I've noticed that the temp needle on my 89 325i starts creeping 
upwards whenever I leave it idling for very long with the A/C on.  A month or 
so ago it was about 85 degrees out and I was stuck in bumper to bumper 
traffic for about an hour or so.  I noticed towards the end that the needle 
was well past the 3/4 mark on the guage and approaching red.  I shut down the 
a/c and the temp dropped down fairly quickly.  I've noticed it getting warm 
like this (not as much though) other times when it idles with the A/C on.
I'm wondering if this is normal.  It hasn't gotten hot enough to make me 
think the engine was in any danger. . .yet.  But I live in central texas and 
it will be getting a LOT hotter this summer.  I just want to be ready for it. 
 I remember hearing about a low and a high speed on the aux fan, and some 
reason why the high might give up.  (H2O temp sensor in bottom right hand 
corner of radiator perhaps?).  Somebody please refresh my memory, and let me 
know if I'm being paranoid.
Thanks in advance,
Jake
Bryan, TX
89 325i ('s'ified)

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