Is Phil's forecast accurate?

So Spring is on its way?  Yessirree, according to Punxsutawney Phil.  Today is Groundhog Day in the US.

Because the weather hereabouts is rainy and cold, Phil did not see his shadow this morning.  Neither did Staten Island Chuck.  According to tradition, if the groundhog does not see his shadow, Spring will arrive early.  That is welcome news to those dealing with heavy snowfalls or otherwise subject to winter weather advisories right now.   The prediction means that we can look forward to less of this.

Still, there are doubters.  The Guardian (UK) wondered about this and conducted an analysis of groundhog predictions dating from 1999.  Here are the bases for its analysis.

"... We have taken snow cover in North America for February of every year to 1999, but this alone does not tell us if the groundhog was right about winter ending. To work this out we need to know how snowy a given February was relative to an average February. We calculated the mean average snowfall for a February in North America using data from the last 10 years, then we subtracted this average from the snowcover for the particular year. This gives us an indication of the severity of the winter for that year relative to the other years."

Although the "study" recognizes that there is scope for further investigation, its conclusion is that groundhogs have predicted the weather accurately only three times in the last ten years.

You can see the full data used in the Guardian's analysis here.   Have fun and we'll all see together whether the "predictions" of Phil and Chuck come true in 2011.