I was told to take a urine sample and bring it in the next day will the temperature effect what they are testing for?

Absolutely: Urine samples taken at home should be immediately refrigerated (& labled) to prevent false levels for bacteria counts. If you can transport the specimen in a cooler chest with ice packs, that will help, too.

It depends.: This would depend on how high the temperature is/was where it was kept, and what is being tested. Apparently, if it was not artificially heated, and was kept at a reasonable temperatture, like room temp. Or lower, it should not be affected for most urine values. However, the big issue with temperature is if high, it might cause growth of bacteria, which can be a big factor if testing for uti.