Tom Thunstrom of PhillyWeather.net: Forecasting weather in Philly is tougher than in Minneapolis

Tom Thunstrom’s interest in meteorology ‘blew up’ in to a fascination as a kid growing up in Minnesota.
He was interested in the snow and the cold, but there was something about watching a tornado pull debris into the sky that changed his perspective.
Today, Thunstrom, in his mid-30s and living Royersford in Montgomery County (after moving here for his wife), has kept that fascination alive. This summer, Thunstrom, who is the Philadelphia senior program manager of Operation HOPE, an economic tools and services providers for the underserved, celebrated five years publishing PhillyWeather.net, a blog featuring surprisingly detailed, lucid and informative writing on the region’s climate and weather. Now he’s in the thick of his busy season — a snowy winter.
“In the end, I want us to be good at what we do and keep the masses informed without hysterical levels of hype,” he says, noting hopes to dive deeper into the sharing of information and data in new ways in the future.
If it’s going to snow and you want to really understand why it will and how you can follow the science of it all, PhillyWeather.net is where you want to go. A guy with a bow tie in front of a green screen Thunstrom is certainly not.

“Meteorology has been flipped on its head over the last 20 years and technology has driven much of that,” Thunstrom, who has two other contributors to the blog, tells Technically Philly. “Computer-assisted forecast modeling has improved forecast accuracy and also have improved mid-range — two weeks — and long range — month plus — forecast trends.”

Using the tools available to him and a voracious summer reading and research hobby, Thunstrom does much forecasting on his own.
Indeed, Thunstrom is something of a fanboy to a weather and climate-gathering movement, but, like many who are passionate and persistent in a love, he has learned plenty in more than a decade of paying close attention to the tools and five years of publishing what goes into your five o’clock news reports.
He shares three of his biggest lessons in forecasting weather here:

1. “[Our website] traffic is substantially higher in general during the winter… As a result, we provide more updates on potential storms and winter weather from December to March than we would in August since the weather in August is a bit more mundane,” Thunstrom says. “I’m not sure if it’s because our local obsession with going to the Acme for bread and milk before a flake flies or if it’s something bigger.”
2. “Philly… average[s] just 10 inches less snow a winter than Barrow, AK,” he says. “Yeah, they only average out to about 30 inches a year as they’re in a desert climate. We average out to about 20 inches although it’s rare to have an average year. It’s either all or nothing it seems.”
3. “I think forecasting weather in Philadelphia is tougher than it is in Minneapolis, especially with storms,” he says. “There are more variables at play in weather here that can foul up a forecast very easily. The Atlantic can moderate temperatures and turn a snowy forecast into a rainy reality or enhance rain or snow by providing more moisture off the ocean. Minneapolis is not as prone to big snowstorms as we are although it snows more annually as they are in a colder climate. We have had more 20-inch snowstorms in our history than they have – thank you Atlantic!”

Technically Philly also asked Thunstrom for his thoughts on what kind of winter to expect:
“Regarding the rest of the winter, expect a lot of volatility in February,” he says. “We’ll have mild breaks in the weather followed by at least one more pretty decent cold outbreak. Philadelphia’s only experienced back-to-back 40-inch snowfall winters once — that was in the 1970s. That’s tough to do, but a winter total in the 30-35-inch range is not out of the question at all. The brunt of the upcoming cold through late January stays in the Midwest. We’ll be cold but not as bad as it will be in Minneapolis or Omaha, thankfully.