Weather
By Dan Skeldon
“It’s the only job you can always be wrong all the time and not get fired.”
Yes, it’s true. Meteorology is an “inexact” science, and blowing a weather forecast has resulted in many an email in my inbox or comment on my Facebook page similar to the above over the years. And there’s been much worse of course, that’s not fit for print. But I do take issue with the “always” implication in the opening critique. In my two-decade career alone, we’ve made significant strides in forecasting, and accuracy is as high as it’s ever been. But that doesn’t mean an occasional forecast doesn’t work out as planned.
Coincidentally, there’s no other time of the year more likely for a forecast to go awry than the early to mid-spring, or roughly from late March through the middle of May. In fact, it was just last Thursday (March 25th) when spring through its first curve ball, and low clouds which were expected to burn off never did, and temperatures sat closer to 60 degrees instead of surging into the forecast 70s. (Of course, the next day worked out as planned, and last Friday saw temperatures soar into the mid 80s!). It was the first bust of the spring, but it likely won’t be the last.
South Jersey weather is always fickle and there are challenges for meteorologists in each and every season. Summertime thunderstorms can rapidly develop and hit hard and fast. Look no farther than the June 2012 derecho for that. Tropical systems bring their own set of complications each fall. We all remember one or more winter storms when a foot was forecast and only a few flakes fell, or conversely when we went to bed expecting to wake up to an inch of snow and there was instead eight inches waiting when we woke up the next morning.
While the spring doesn’t usually offer up strong and destructive storms, the challenges that the spring season present are more subtle but also more numerous. The biggest temperatures bust each year, meaning a given day is either much warmer or much cooler than expected, are most commonly found in the spring. Likewise, the biggest sky cover busts, meaning that a given day is either much sunnier or much cloudier than expected, also occur this time of year more than any other.
Why? We largely owe it all to that big body of water that sits just to our east, the mighty Atlantic Ocean. To be more specific, we can blame the fact that ocean water takes a longer time to warm up each spring and summer compared to the air. Yes, the ocean is still quite cold in the spring, even when the land heats up. Take last Friday for instance, when the air temperature at the beaches soared into the mid 80s, while the ocean temperature sat in the mid 40s.
The cold ocean is one part of the complex spring weather equation. Any wind off that ocean increases the complexities. Spring sea-breezes can keep the islands in the 40s, given that is the temperature of the ocean that the wind is coming off of. But head 20 miles inland, and it can be summer-like and above 80 degrees. On the extreme side, I’ve seen several a South Jersey day when Margate is around 45 degrees with a marine layer and low clouds, Mays Landing is 65 degrees with clouds and some peek-a-boo sun, and Hammonton is 85 degrees with sweltering summer sunshine. What’s challenging about a 40-degree temperature-spread over just Atlantic County?
Winds off a cold ocean can also lock in clouds and fog, which can sometimes be stubborn to leave once they settle in. There is seemingly always more than a handful of forecasts for sunshine each spring spoiled by some fickle fog or an obstinate overcast of low clouds. Get the sunshine forecast wrong, and an incorrect high temperature forecast will obviously follow.
And then there’s the notorious “back door” cold front, a feature that usually occurs only in the spring and only along the Northeast and Mid-Atlantic coast. Cold fronts normally move from west to east across the country and through South Jersey. Back door fronts sneak “backwards” down the coast from New England. While they seldom bring any significant rain, they are known for instantly changing a mild and sunny spring day to a cool, cloudy, and brisk one. Temperatures can drop 20-something-degrees in less than an hour as a back door front slowly slides down the shore. It’s real fun for forecasters when that front stalls over South Jersey, and Cape May County is on the sunny, warm side and Atlantic County on the cooler and cloudier one.
Thanks to the colder ocean, getting a nice spring season from start to finish is difficult but not impossible to accomplish. So is getting through a spring with no blown forecasts. Here’s hoping we’re lucky on both counts going forward this season!
Meteorologist Dan Skeldon has a degree in meteorology from Cornell University. He has forecasted the weather in South Jersey for the last 18 years, first on the former television station NBC40 and then on Longport Media radio. Dan has earned the American Meteorological Society Seal of Approval for Broadcast Meteorologists, and now does television broadcasts on WFMZ-TV in Pennsylvania’s Lehigh Valley.
