The meteorological setup for this late-week storm is driven by a strong ridge of high pressure building over the western United States. This ridge is facilitating the southward movement of colder Canadian air into the Northeast, while simultaneously allowing warmer air to build across the West. This temperature gradient provides the necessary upper-level energy and lift to support a strengthening area of low pressure. The dip in the polar jet stream is allowing the storm to originate somewhere between the Great Lakes and the Ohio Valley. Furthermore, the unusually early disruption of the stratospheric polar vortex high above the Arctic has contributed to supporting this larger-scale weather pattern.
Despite the clear large-scale drivers, forecast models continue to display uncertainty regarding the specific track and impacts of the potential nor’easter. Two primary scenarios have emerged from current modeling. In the first scenario, an initial area of low pressure tracks inland across the Ohio Valley and eastern Great Lakes before transferring its energy offshore. This development would allow a secondary coastal low to form. Under this setup, the immediate coast and the I-95 corridor would remain on the drier side, while inland and higher-elevation areas could receive accumulating snow.
The second scenario suggests the nor’easter will track much closer to the Eastern Seaboard. In this case, the storm would develop nearer to the coast, bringing more significant impacts to those areas, including periods of heavy rain and gusty winds. Inland snow accumulations in this scenario would likely be limited by a lack of sufficiently cold air, confining the heaviest totals to higher elevations. A wildcard in this second track is the possibility of the storm moving farther offshore into the open Atlantic. A track too far east could push precipitation away from the coast, significantly reducing the potential for coastal rain and wind while also limiting snowfall inland. While this offshore track is not currently favored, it cannot be ruled out given the number of days remaining before the storm fully develops.
Regardless of the final track, a wave of low pressure is expected to organize across the Ohio Valley late Wednesday before tracking toward the Mid-Atlantic and Northeast by late Thursday. The developing system is expected to spread widespread rain across the East. Accumulating snow is most likely to occur across the higher elevations of New England and the interior Northeast. Although cold air will be limited, some snow is expected across parts of Maine, Vermont, New Hampshire, and upstate New York, with precipitation potentially extending south into the Appalachians. For areas closer to the coast along the I-95 corridor, any snow that mixes in is unlikely to accumulate due to intermittent rain, surface temperatures, and the absence of a deep cold air mass.
According to the FOX Forecast Center, the system will begin taking shape as it moves across the Great Lakes and Ohio Valley. At this initial stage, the low-pressure system will remain relatively weak and disorganized, producing scattered light rain with minimal impacts. By Thursday, the initial low will advance toward the Northeast. With cold air remaining to the north, precipitation will be mostly rain. Scattered showers could reach the I-95 corridor, causing minor travel delays, but overall immediate impacts are expected to remain limited.
By Friday, the low will track toward the coast and attempt to strengthen. The best chances for accumulating snow will be concentrated across northern New York, Vermont, New Hampshire, and Maine. If a secondary coastal low fails to develop near the Mid-Atlantic, impacts along the I-95 corridor would likely remain minimal, while snowfall totals farther inland could be lighter. However, if a secondary low develops farther south and offshore, the coastal corridor could experience stronger wind gusts and potentially a brief transition from rain to snow on the back side of the departing system.
By Saturday, the storm is expected to pull away toward Canada. However, moisture and colder northwesterly winds could bring lingering snow showers from Maine south through the Appalachians, including parts of upstate New York and central Pennsylvania. Behind the departing storm, a late-autumn air mass will settle across the region, sending afternoon temperatures into the 30s Fahrenheit for more than 110 million people across the Northeast and surrounding areas.
The temperature swing associated with this event is substantial. Beginning late Friday, cold air from Canada will spread across the eastern United States. High temperatures could remain in the 30s or 40s across the Northeast, Great Lakes, and Ohio Valley, with lows plummeting into the 20s. There is also a possibility that this cold air could reach the Gulf Coast and Florida by Sunday. To illustrate the scale of this shift, the FOX Forecast Center notes that on Tuesday, over 300 million Americans were above average temperature, with only a little over 4 million below average. By Saturday, that number is projected to exceed 160 million Americans below average, potentially rising even higher into Sunday.
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