By Eric Snodgrass
Each year on February 2, we have a long standing tradition of asking a groundhog in Pennsylvania his opinion on the weather for the remainder of winter and the start of spring. The tradition goes back over 130 years, and the most famous of groundhogs is ‘Punxsutawney Phil’ from Pennsylvania.
The idea is simple - if the groundhog sees its shadow, the forecast calls for six more weeks of winter. No shadow, and we should expect an early spring. Of course, this tradition has no actual scientific reasoning, as the groundhog has no predictive skill. But, still it happens, and an important fact to consider is that astronomical spring always starts about six-and-a-half weeks after Groundhog Day on March 21-22. This day is called the Spring Equinox, and on that day, everywhere on Earth has 12 hours of daylight and 12 hours or darkness, except the north and south poles.
But, getting back to the groundhog, the big question is should we trust its forecast? Over the last 130 years or so, the groundhog has predicted an early spring 17 times. Ten times he didn't come out due to the US being in war, but the other 100+ times, he has predicted six more weeks of winter. So, what is the groundhogs accuracy?
According to the National Climactic Data Center, the groundhog has been right only 38% of the time. That's worse than flipping a coin! So, how about some real data to chew on with regard to the arrival of spring?
At the Agrible Headquarters, our temperature records extend back into the late 1880s. Over that time period, the average date of the last freezing minimum temperature is April 19. Since 1990, 21 of the last 26 years have had an earlier last freeze date. It appears that spring is arriving sooner, regardless of the groundhog’s best guess.
In addition to this, while February will have bouts of very cold temperatures (as it always does) - like the cold air that is set to invade the cornbelt by February 8-10 - the long-range forecast for the whole month puts a slight warm bias for most of the US. That forecast is supported by the Climate Prediction Center, as well as long range models like the European Model (ECMWF). That being said, if the groundhog consults with the experts this year, I would recommend he go with not seeing his shadow - meaning an early arrival of spring!
For more weather knowledge and weekly updates on US ag weather forecasts, check out Eric's weather videos on Morning Farm Report every Monday morning.