I forgot to pick up the hops from the homebrew store I was at and have the mashed wort ready to boil but no hops. Are there certain precautions or a certain way to store the unboiled wort until I pick them up tomorrow?
Just keep it covered and boil again the next day. Hopefully some stray yeast floating around in the air doesn't start things, highly unlikely. Boiling will kill anything that would be floating around in the air. If you lost some volume to evaporation, you can always top up with more water while you are boiling or boiled water after you are done boiling. You should be GTG once you start boiling again.