By Kennedy Elliott and Shelly Tan Jan. 31, 2015 at 4:56 p.m. UTCshareEditor's note: Our colleagues in the Graphics department had a burning question: can groundhogs really predict the weather? They ran the numbers on 250 cities over 30 years. Here's what they found out.Support our journalism. Subscribe today.arrow-rightThe previous headline misstated the number of years mapped. The headline has been corrected.Today's HeadlinesThe most important news stories of the day, curated by Post editors and delivered every morning.