Weather Journal: A Cold Day Before Another Snowstorm

Greater New York will be stuck between snowstorms Monday, as brisk winds chill the air ahead of another brewing storm.

The entire tri-state will face another round of possibly heavy snow on Tuesday evening, even as southern Connecticut continues its recovery from the past weekend’s snows, which left a foot or more of snow behind in some places. This newest snowstorm is already causing massive headaches down south, and will probably rank somewhere between the last two in severity by the time it reaches our area.

The National Weather Service in Upton, N.Y., has issued a hazardous weather advisory in anticipation of the next storm, mentioning that “heavy snowfall accumulations in excess of eight inches are likely”. Blizzard conditions may again return to the Big Apple, as winds are forecasted to gust up to 35 mph or more.

So batten down the hatches — it’s gonna snow on everybody around here. It’s too early to predict snow totals just yet, but stay tuned to Weather Journal on Tuesday as we provide full coverage of this new potential blizzard.

Friday Snowstorm Recap: Although Friday’s snowstorm turned out to be not much more than a dusting for much of New York City (Central Park recorded 1.7 inches, officially), it could have been much worse. Weather Journal’s pre-storm forecast included a mention of the “worst case scenario” — the risk of a quick 10 additional inches on top of the three to six inches more widely expected — and the possibility of a crazy snow map as a result.

This scenario actually panned out in southwest Connecticut, just about 20 miles east of our forecasted “line of maximum snow” — well within the uncertainty of our forecasted snow map. Several spots in Fairfield and New Haven counties received in excess of 12 to 15 inches of snow overnight, which ended up shutting down I-84 for several hours as a tight band of heavy snow moved from northern Westchester County towards New England. In one “crazy map” example, the town of Somers, N.Y., in northern Westchester received 10.5 inches of snow, while 25 miles south White Plains received less than three — that’s one amazingly tight snow gradient!

The reality is that if the storm had shifted in the opposite direction (west instead of east), Mayor Bloomberg’s extensive preparations might have ended up being called into full force for the five boroughs. So why so little snow in New York City?:

In addition to the extremely tight snowfall gradient we thought might set up thanks to the Norlun trough, air temperatures during the entire event remained stubbornly a degree or two above freezing, causing snowflakes to melt on impact with city streets. These two factors combined ended up making accumulating snowfall in the city less likely, even though snow was hard at times throughout the day. Had these chance factors gone the other way, the city could have easily tripled its actual snow total.

Luckily (or not), we’ll have another chance this week.