Originally published by AccuWeather.
A storm packed with moisture will unleash heavy rain in the eastern United States prior to the end of 2024. The rain may not only put a damper on skiing but may also hinder travel due to flooding, spotty ice, and fog.
A gathering storm over the south-central United States will bring heavy rain and the risk of urban flooding to parts of the Midwest, Appalachians, and Atlantic Seaboard from this weekend to early next week. AccuWeather meteorologists also warn that just enough cold air will be around on the front end of the storm to produce a glaze of ice in some areas.
Soon after one storm triggers severe weather and downpours over parts of the South Central states into Friday, a second storm will spring up and roll northeastward while tapping into a stream of Gulf of Mexico moisture beginning this weekend.
Much of that rain may fall during a four-to-eight-hour period, enough to push small streams up to bank full and potentially trigger small stream flooding. At the very least, significant and rapid runoff onto streets and along secondary rural roads will lead to flooding. In mountainous areas, there can be some debris that gets washed onto the roads.
The heavy rain can be especially troublesome in southern Appalachian areas ravaged by Helene in late September. Much of the infrastructure still needs permanent repair, and some people are still living in temporary or makeshift shelters. Stream beds and storm drains that are filled with rocks and debris can flood easily.
As the storm continues to move along, the ribbon of moisture containing the heavy rain will pivot from the Appalachians to the middle and southern Atlantic coast and New England from Sunday midday to early Monday. The heaviest rain along much of I-95 is likely to be from Sunday afternoon to Sunday evening. During this time, poor visibility, downpours, and urban flooding will lead to substantial travel delays. Shifting travel time to well before or after the storm leaves may be a better option, when possible.
Watch for icy patches.
Just enough cold air will linger in the lower part of the atmosphere, along with some cold surfaces, to raise the risk of patchy ice over the interior Northeast as the main storm arrives.
“Similar to Thursday morning over the higher elevations of the central Appalachians, a more expansive zone of freezing drizzle will extend from western Maryland through portions of western, central, and northern Pennsylvania and part of the southern tier of New York and last through Friday morning,” AccuWeather Meteorologist Brandon Buckingham said.
“A more substantial zone where glaze of ice can occur is likely from Friday night to Saturday morning from western Maryland to north-central and northeastern Pennsylvania, northwestern New Jersey, upstate eastern New York, interior Connecticut, western and central Massachusetts, and the southern and central parts of Vermont and New Hampshire,” AccuWeather Senior Meteorologist Dave Dombek added.
From Saturday night to Sunday morning, the icy zone may extend from the northeastern corner of New York to the northern parts of Vermont, New Hampshire, and much of Maine.Milder air with plain rain will reach all the way to the Canada border. That means that, aside from some icy conditions for a time, the snow on the ski slopes over the northern Appalachians will tend to get soft and slushy in many cases.
Even a thin glaze of ice that is patchy and not widespread can be dangerous for motorists and pedestrians. Surfaces may appear wet but can have a thin sheet of clear ice instead. Ice of this nature can form even where air temperatures are a bit above the freezing mark, 32 F.
Milder air and moisture often lead to wintertime fog
Long nights and moist air are the perfect ingredients for fog in the wintertime. The fog can be especially dense as a storm is moving in over snow cover or even just cold ground.
Full-length man wearing sports clothing and red headphones running on the road in foggy weather condition.
As the storm pivots, two types of fog can occur. One will be low-level fog near the ground, and the other will be associated with low clouds that can obscure the ridges and make for poor visibility for motorists on the highways and aircraft as they attempt landings and takeoffs. Substantial delays due to the dangerous conditions can occur.
Same storm to spark severe weather in Southeast
The intensity of the storm will be great enough to produce gusty and locally severe thunderstorms from the central Gulf Coast to the Tennessee Valley on Saturday and then the southern Atlantic Seaboard on Sunday.
A couple of tornadoes may occur in the strongest storms with the most widespread threats being strong wind gusts and flash flooding.
Watching for more storms next week
Soon after the big rainstorm leaves the region, a trailing storm could tap into just enough cold air to bring accumulating snow to part of the interior Northeast from next Tuesday to New Year’s Day.
At this time, the storm is likely to deliver rain to the coast, including the major I-95 cities of the Northeast, with the potential for snow farther inland. However, a shift in the storm track could change which areas get rain and which areas are blanketed by snow.
A potential third storm could have colder air to work with near the coast. From late next week to the first weekend of 2025, a portion of I-95 and some interior locations will be watched for wintry trouble.
