Humidity (low is better) is more important than temperature. If the leads get corroded the solderability suffers and they may no longer be easily or reliably useful. Maybe you could put them in air-tight plastic food storage containers with some fresh dessicant, though a basement would probably be better than a garage (cool and dry is best). Garages also tend to have a big door that (if opened) can let the temperature inside change rapidly, leading to condensation if the items inside are cooler than the dew point of the air that comes in. This is why a garage isn't a great location for machine tools - they tend to rust.
In you are reflow soldering, many parts should be baked to remove moisture from the plastic packages before they go in the oven, but that's not often a concern for hobby parts. Hand soldered (with an iron) J-lead parts are typically not a problem, but hot air reflow of QFN and similar packages could well be.
Parts can generally be exposed to long term outside air temperatures that exist anywhere in Michigan without damage. Some parts will tend to last longer if kept cooler, with most (especially semiconductors) it won't matter much.
Regarding baking, here is an excerpt from an article in Circuits Assembly magazine (MSD = Moisture Sensitive Device)- note also that the "packaging" referred to is the tape and reel or tray the IC is shipped in rather than the IC package itself:
Baking MSDs can permanently damage the plastic tape and reels,
carriers, carrier tape, tubes and trays used to dispense the
components. Damage can occur at temperatures as low as 45°C (113°F),
making it impossible for placement machines to process these parts.
Baking exacerbates oxidization4,5,6 on the MSD’s solder terminations, one of the biggest causes of poor solder quality.
Baking takes a long time: up to 79 days for somewhat thick (2 to 4.5mm) components at the package safe low temperature of 40°C (104°F) to as little as 3 hr. at a package melting temperature of 125°C
(257°F) for MSDs with MSL 2, with exposure time PAST the expired
floor life less than 72 hr. Clearly the higher the temperature, the
shorter the bake time, unless components can be unpackaged, baked at
a very high temperature and then repackaged at a safer 40°C (104°F)
temperature. At this safer temperature, bake times start at five days
and can go up to 79 days.
Baking consumes at least 20 times the energy as that of simply keeping the parts dry.7 And, since most MSDs do not require baking
unless they are MSL 6 or the floor life was mistakenly exceeded, it
would more reliable and economical to keep the parts dry rather than