How critical is it to store spices in constant temperature? A typical bit of advice on the subject says:

Store your herbs and spices in a cool, dry place. The ideal temperature is one that remains fairly constant, averaging right around 70° F.&quot;

You're also supposed to keep them dark and dry.
I do this by keeping my spices in a drawer, but I'd really like that space for something else, and to put my spices in opaque magnetic jars on the fridge. The opaque jars would keep out the light, and the cap would keep out the moisture, but my fridge is only two feet away from the stove, and there's probably more light, moisture, and temperature variation there than there is in the drawer.
Is this difference worth worrying about?
The small temperature variation is probably not as important as buying whole spices, then toasting and grinding small amounts when you need them. Pre-ground spices lose their flavor and aroma very quickly.