ok temp gauge acting funny!! whats wrong now?

[240silvia]

ok well the weather here has been gettin kinda cool lately, bout low to mid 50's at night, so anyway this is my setup, stock 92 ka24de w/ 80k, fan clutch removed, with ac fan running all the time, no ac condesor infront of the radiater. now during the day when its low to mid 80's outside the temp gauge reads normal at the half way point, which is good. but at night when it cools down i noticed a signaficant drop in the temp gauge, the gauge reads halfway between the first and second mark after the C. well i didnt think anything of it till i had turned on the defrosters and noticed the gauge was reading a lil over the C, sooo i remembered that if ur car overheats that if u turn on the defroster the temp will drop so i turned off the heater and what do u know the temp gauge went up too the second notch, sooo wtf? is this normal or what? soo i notcied that today the gauge was reading bout half way sooo its workin ok just at night when the temp is cooler it reads low as shet.