Breaking down the science of Wednesday’s nor’easter

PROVIDENCE, R.I. (WPRI) — The nor’easter that moved through Wednesday night had many interesting components, including huge snowflakes and snow that was extremely wet and heavy.

The weight of the snow was enough to bring down a power line in Johnston.

“Just from the weight of the snow,” electrician Dennis Parrillo said. “It’s about 120 feet on the run from the pole to the house, and it just took the wire right down.”

Snowfall amounts showed big differences by just small distances; they ranged from around a foot in northern Rhode Island to barely a coating along parts of the south coast.

Very wet, heavy snow tends to fall when temperatures are borderline freezing in the bottom layer of the atmosphere down to the surface. A computer model simulation during the storm showed temperatures were easily cold enough for snow 10,000 feet high, but hovered near freezing from 3,000 feet down to the surface.

A 2008 article from the Washington Post’s Capital Weather Gang looked at giant snowflakes, and pointed out that when temperatures are borderline freezing, snowflakes might partially melt, which makes them sticky enough to collect others, eventually forming one big snowflake.