Summarize this article in one sentence.
The juice will flow more easily if the lemon is warmed, so let it come to room temperature on the counter, place it in warm (not boiling) water for 3-5 minutes, or microwave it for no more than 10-15 seconds. This is only necessary if the lemon was in the refrigerator.

Summary:
Bring the lemon up to room temperature if it's chilled.