You're using it all quickly enough that most of it doesn't matter. Infolpl your house is air-conditioned, it probably wouldn't even be a big deal if you left the yeast out, but I still wouldn't recommend it.
I would just stick it all in the fridge though.
Yeast should DEFINITELY be kept in the fridge regardless, but if you're storing longer-term, hops are best kept (in order of priority) in an airtight container in the freezer, with minimal UV exposure.
Grain can be kept anywhere at room temperature or cooler, though if it's stored for extended periods it should be COMPLETELY airtight (that is, with no ability for external humidity to get in.) Crushed grain can last at least a few months, but uncrushed grain can last AT LEAST a couple years before staling, if stored properly. Darker grains (especially roasted grains) can last longer than less-kilned grains. Some people recommend putting grain in the freezer for a week to kill weevils (little bugs that live in grain), but this is unnecessary if you're storing properly. Merely keeping bugs from getting in is not enough as there will usually be eggs in the grain which can hatch with sufficient moisture. I have 250lbs of uncrushed malt in my basement, and like many (probably most) people who buy grain in bulk 50/55 pound bags, I store it in 5-gal buckets (each one holds half a bag). A lot of people use the lids with foam gaskets that often come with these buckets in order to make an airtight, bug-tight container, but they are not good enough. Not only can they "dry up" and become brittle and start letting bugs in (and I've even seen evidence of bugs biting the stuff to get through it!), but they are not actually capable of preventing moisture exchange, and so it can still cause the little bastards to hatch, reproduce, and infest your grain.
Some people deal with this buy getting expensive containers called Vittles Vaults, which were originally marketed for pet food, but are used to store all sorts of staple food items. The thing that makes these containers so effective is the lid though, and thankfully, they now sell the exact same lid separately (called a "Gamma Seal Lid") for use with 5-gal and other 12"-diameter buckets. Most cost effective way I've found for truly airtight bulk storage, and will allow grain to reliably last for years without any noticeable staking, and pretty much eliminates any chance of bug problems. The lid is also designed with stacking in mind, not only having raised "lips" to neatly fit the bottom of a standard bucket, but has way more strength than a typical lid as well.
I apologize for getting a bit off-topic there, but I figure that many of the people wondering about short-term kit storage will eventually have similar questions later on about long-term and/or bulk storage.
Hobnob said:
There is a lot of moisture in the fridge
False. The air in a fridge is notorious for an incredible LACK of moisture. Generally, you want to seal things up to prevent them from totally drying up.