“The weather is unpredictable.”
“If you don't like the weather in New England, wait five minutes.”
“If you've lived here long enough, you know you don't trust expectations.”
Sure, there are some partial facts, but overall, the weather forecasts are trustworthy and based on solid scientific foundations.
In this day and age, this could be construed as blasphemy – or even “fake news” – but like many science-based professions, meteorology is heavily criticized, and is often relegated to abstract status. Like all scientists, we take pride in our work, our livelihood, and our outlook. Like all scientific disciplines, we strive to decipher what went wrong when things go wrong. It's literally forensic meteorology about what led to the forecast, where it went off track, and what we can do better in the future.
This storm, like two others last year, is disorienting in its sudden deflection just as we run out of snow amounts. Confidence in 6 inches of snow was 73% in Boston and 87% in Worcester (see below).
With these percentages, no one will refuse to dial up snowfall maps, impacts or preparations. The bigger question is what led to it moreTrust in models, and how (or if) we can compensate.
Distinguished colleagues at MIT would argue that even in a warming world, models can handle a variety of outcomes in projections. On the other side of the country, at Stanford University, atmospheric researchers have predicted that for Earth's midlatitudes, where most Americans live, errors propagate through weather models faster as temperatures rise, and there do not appear to be any temperature thresholds where they shift. direction.
The implications for winter weather are enormous, of course. High-intensity rain events can also be affected, because as the temperature rises, warmer air can hold more water vapor (and produce more rain).
Whatever the explanation, in our current case we know that dueling jet streams were competing for control of the storm's path. Models tried to split up – or merge – the jet streams, but failed miserably. Instead, the storm was channeled by the north branch of the jet stream, preventing it from moving deeper into New England, and sparing much of the commonwealth more than 6 inches of snow.
While the debate continues about why the model is wrong, we will continue to move forward with prediction (pun intended).
