Does An Unusually Mild Winter Mean A Hot Summer Is On The Way?
By Kate Bilo
PHILADELPHIA (CBS) — Today marks the last day of astronomical winter across the nation, though you’d never know it step outside here in Philadelphia, with temperatures again surpassing the 70 degree mark today.
It’s been a wild winter this year, but certainly not “wild” in the same sense of the past two years – this winter will be remembered for its top-5 warmth and it’s lack of snow.
And so the question we’ve been hearing a lot from people lately is: does a warm winter mean we’re in for a hot summer?
While it’s far too early to make predictions about the summer, I went ahead and analyzed data from the top 11 warmest winters (meant to do ten, but threw an extra one in there – bonus!) and the corresponding summer that followed to see if a mild winter indeed means a scorching summer. And the results are inconclusive at best, as you can see from the chart.
While averaging the numbers for those 11 summers did yield a mean summer temperature roughly 1 degree warmer than the norm, three of the summers were below average and another four were only just above the average. There certainly a few hot summers to be found in that data set, but there is no conclusive evidence that proves a mild winter will spawn a sweaty summer – perhaps just a summer that’s slightly above the average.
Keep in mind, our hottest summer ever on record here in Philadelphia (2010) followed our most brutal winter on record, when we shattered our previous snowfall records by over a foot.
Of course, these data seta refer to meteorological winter (Dec-Jan), and don’t take into account the extreme warmth we’ve had in the month of March thus far. Hence, my next task – find which of the warm winters also had an unusually warm March, and see if there’s any further correlation.
However, just because March is extremely warm doesn’t mean we can pack away the jackets just yet. Nationwide data shows that historically warm Marches are generally followed by a cooling trend in April and May. And even if we don’t have an exceptionally hot summer, a mild winter and early spring can lead to a host of other problems – earlier vegetation means increased insect populations and an early start to the growing season could mean problems for the plants if we get hit by a chilly spell in April or early May.
And remember this past winter, when we got hit by a freak nor’easter in late October and everyone was wondering – does the early start to winter mean it’ll be a bad one? And it most certainly was not. We will be issuing our official summer forecast in May, but until then, enjoy this unseasonably warm end to winter while we’ve got it!