<E30> alternator belt

[E30325is@xxxxxxx]

i have an '87 325is. today my alternator belt snapped. i was at about 5K in 
4th gear getting ready to upshift, when i looked down and saw the following 
warning lights on; battery, brake fluid, parking break. then i noticed that 
my temp guage was climbing at an incredible rate. it went from half way 
(normal) to just touching red in about 2 seconds. the car was running fine, 
but i immediately pulled over anyways, popped the hood, and noticed the belt 
was snapped in half. not having a spare belt or tools with me, i had it towed 
to a local shop, which luckily was within 1 mile of where i was. my question 
is this: would all of these warning lights come on because the electrical 
system was on the fritz due to the batter no longer getting a charge? i can 
understand why the battery light would illuminate, but im trying to figure 
out why the temp guage would do what it did. thanks for any advice.

Kyle B
NCC

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