Anyone who thought winter was done with us must have been surprised by the snowstorm that hit Boston on Saturday. Although in the end it didn’t leave much snow, it reminded many of the massive snow storm that hit the area 20 years ago to the day. And being thus reminded, I dug into the archives to find the following essay I wrote several years ago, originally posted April, 2011. I hope it’s not too late to enjoy.

As the snow began falling Thursday evening, it brought back memories of 1997 — the year Boston was socked with an April Fool’s Day blizzard that dumped two feet of the white stuff on the city. For those too young to remember that storm, let me (and Wikipedia) refresh your memory:

“During the peak of the storm from about 11 p.m. March 31 to 3 a.m. April 1, snow fell in Boston at an almost unheard-of rate of 3 inches (76 mm) per hour, some of the heaviest Boston had ever seen. Numerous lightning strikes and thunderclaps accompanied the extremely heavy snow, which accumulated one foot (12 inches (300 mm)) in just that four hour period. Moderate to heavy snow continued through mid-morning before tapering off.” (Wikipedia)

Unlike the winter of 1997, which was — up until that unusual blizzard — a mild one, 2011 has been a bear of a year for snow. The last few weeks haven’t been bad, but January and February were brutal. I have to admit, I thought we were through with winter. Maybe it’s cabin fever, but I just can’t wait for the first really warm day.

But there’s a group of people that probably hopes it stays cool for a while longer. I’m talking, of course, about all those poor folks who have trained through this miserable winter to run the Boston Marathon. They were out there every weekend in January and February and March, defying frostbite and slippery roads to get in those long runs. They are the ultimate winter warriors, their bodies and minds toughened by the elements. They probably didn’t even notice the snow falling last night. In fact, there’s only one thing that these runners fear… that it will be 70 (or 80 or 90) degrees on Patriots Day.

There is nothing more unfair than training for four months in sub-freezing temperatures only to be hit with a scorcher on the big day. Unfortunately, and despite today’s wintry mix, that nightmare scenario might be the most likely, or so says a researcher from the National Oceanic and Atmospheric Administration (NOAA). Dr. Rolf Paoli, who heads the NOAA’s long-range meteorological forecasting service and is himself a veteran of six Boston Marathons, recently published an article on the NOAA web site that provides historical evidence for a definite weather pattern that has affected Boston a dozen times in the last sixty years.

According to Paoli, the pattern is characterized by colder-than-usual temperatures for up to six weeks in late February and March, culminating in a significant storm (sometimes cold rain, sometimes snow) on April 1st. In every case, this pattern has been followed by a dramatic warming trend within 2-3 weeks. More ominously, in every year that the pattern occurred, the temperature on Patriot’s day exceeded 70 degrees.

Notwithstanding my own hankering for a nice spring day, this is not at all good news for the legions of winter-blooded runners who are not acclimated to heat and will be trying to cover 26.2 miles on April 18th in what might feel like tropical conditions.

According to Paoli, he became interested in the phenomenon after running the 1997 race less than three weeks after that massive April Fool’s Day storm. The temperature on Patriots Day hit 78 degrees and he struggled just to finish. He ended up with a trip to the medical tent (for bad blisters) and a much slower time than he had hoped for. As he states in his article:

“I began to wonder if the weather had ever shifted so suddenly. I discovered it was actually fairly common. What was surprising when I examined the historical data was to see this correlation — almost 100% — between a storm on April 1st and a hot day on the day of the race. It would be foolish to claim that anyone can predict the weather so far ahead with absolute certainty, but the correlation appears to be too strong to be a coincidence.”

Not all scientists share Paoli’s view that there is a cause-and-effect relationship between April 1st storms in Boston and the weather on a specific day almost three weeks later. Researchers in Yale University’s Department of Atmospheric Statistics point out that even a hundred years of data is not enough evidence to draw conclusions. Associate Professor Ari Pollof is quoted to that effect:

“If a convenience store sells two winning lottery tickets, people might think there is good luck involved, but in fact, it is nothing more than an unlikely coincidence. This supposed connection between snow on April 1 and the weather for the Marathon is similar — it is curious, but ultimately the product of pure and simple chance.”

Still, according to this statement on the BAA web site, the race is taking no chances with what might simply be a matter of chance. The strange connection between April 1st snow and a Patriots Day heat wave has, apparently, caused them to plan for more water consumption and more utilization of on-course and post-race medical facilities for treating heat-related injuries.