A strong winter storm will drop the first significant snow of the season across parts of the Northeast this weekend, bringing up to a foot of snow in some places — though which places, exactly, remained uncertain on Friday morning.
Forecasters said the final details of where the division of rain and snow will exactly line up may not be known until the storm is underway on Saturday.
“The greatest uncertainty in the rain-snow transition is from southeast Pennsylvania and northern New Jersey into southern New England,” forecasters with the Weather Prediction Center wrote Friday morning. “People in those areas should still be prepared for the possibility of snow and changes to the forecast.”
There is at least a slight chance that cities including New York — where the emergency management department on Friday warned residents to prepare for “snow, rain, breezy winds, and minor coastal flooding” — may still squeak out an inch of accumulating snow or more through Sunday. It has been almost 700 days since Central Park last received an inch of snow in a single day.
Why don’t the meteorologists know what to expect by now?
The hesitancy in meteorologists’ forecasts comes down to subtle differences in the weather computer models of precisely where the storm tracks.
The Weather Service in New York said that if the storm tracks farther offshore, or if it is more robust, the division between rain and snow will move southeast, resulting in higher snowfall totals for New York City and the coast.
A weaker system may allow warmer air to infiltrate further inland and lead to more rain than snow.
On Friday morning, forecasters said the most recent trend in their computer models indicated a secondary burst of energy toward the end of the storm on Sunday. This additional energy could prolong the precipitation into much of the day on Sunday and provide more opportunity for cold air to infiltrate areas closer to the coast.
This final burst is expected to be pretty light in intensity, but it could allow for some minor accumulations of an inch or less for Long Island and the New York City metro as the storm winds down.
A larger, more powerful storm will follow this one.
The next storm system is expected to be stronger and warmer, and its affects will be much more widespread. It will intensify into a dynamic storm over the Great Plains and cause impacts from there to the East Coast from the early to middle parts of next week, forecasters said.
Excessive rainfall from Texas to the Northeast will be a significant factor with that storm. This means that any snow that falls on Sunday could be washed away by heavy rain by Wednesday, increasing the chances of floods in places hit by both. The second storm is also expected to have even stronger and more widespread winds across the eastern half of the country.
On the northwest side of that storm system, there is likely to be an impactful winter storm from Kansas to the western Great Lakes, including possible blizzard conditions. On the southeast side, across the South, severe storms are likely, with tornadoes possible.
Forecasters warned people to be prepared for the second storm system, because the region will only have about 48 hours of relative quiet before some places begin to experience the effects of this next storm.