Higher temperatures will allow wood to dry faster, as it increases the capacity of the surrounding air to hold moisture. Another way to say this, is it lowers the air's relative humidity.
Alternately, putting the wood in a drier environment will also speed up the process, even if the temperature remains unchanged.
When you're measuring with a moisture meter, keep in mind that the wood dries from the outside, and there will be a gradient with the outside being drier than the core, so you need to measure deeper than just the surface. Also, keep in mind that pin moisture meters are very affected by temperature (both of the wood being measured, and the surrounding air).
If you'd like to play around with how each of those two variables affects the drying process, look up an EMC (equilibrium moisture content) calculator online, and see how changing temperature and relative humidity changes the answer. The lower the EMC, the more effective your drying process will be. (Since you're working with firewood, you don't have to worry about the cracks and splitting that other moisture meter users do).
Source: I work for a meter manufacturer.
