A major storm with drenching rain, gusty winds and the risk of flooding will accompany temperatures more fitting for March and April in the northeastern United States early next week.
Additional strengthening is likely as the storm makes a northward turn along the Atlantic Seaboard during Sunday night, Monday and Tuesday.
"Enough rain will fall to cause street and poor drainage-area flooding," according to AccuWeather Senior Meteorologist John Gresiak.
Rain, combined with fog and wind, can cause significant travel delays.
Motorists will face poor visibility for their commutes along Interstate 64, I-70, I-80, I-81, I-95 and other major highways. Airline delays are likely at the major hubs from Washington, D.C., to Philadelphia, New York City and Boston.
"Strong winds blowing in from the ocean will lead to a period of above-normal tides and the potential for minor coastal flooding," Gresiak said.
If the storm develops to its full potential, winds could become strong enough to down trees and cause sporadic power outages.
Enough rain with warmth can occur to melt some of the existing snowcover in northern New England and upstate New York. Should the rain be accompanied by temperatures surging into the 50s and 60s, rapid melting could occur that causes substantial stream flooding and ice jams in these areas.
Farther south, where there is little or no snowcover and streams are flowing with little or no ice, the threat of river flooding will be minimal.
The rainfall will help put some water back into area lakes and reservoirs throughout the region.
According to the United States Drought Monitor, much of the Northeast is experiencing a long-term rainfall deficit with moderate to extreme long-term drought in some areas.
The storm will also produce some wintry precipitation, despite the overall unusual warmth for January over much of the eastern two-thirds of the nation.
Initially, the storm will run into a zone of chilly air over the interior mid-Atlantic and New England. It is possible a period of wet snow and ice occurs prior to a change to rain with warmer conditions.
With the temperature pattern similar to that of March and April, the storm may also behave the same way. Sometimes, intense spring-style storms such as this can create a pocket of cold air west of the coastal areas.
"We cannot rule out a period of wet snow for some of the higher elevations over the central Appalachians during the middle and latter part of the storm," according to AccuWeather Senior Meteorologist Brett Anderson.
This means that for some interior locations rain could change back to snow.
The potent storm early next week will follow a different, weakening storm that is scheduled to bring areas of light rain and drizzle to the mid-Atlantic and the Washington, D.C., area on Friday.
Rain from the weak storm may struggle to reach New England Friday night and Saturday.
Otherwise, the unusually warm weather pattern for January will continue until nearly the end of next week, when more seasonable air will arrive.
Temperatures during the latter half of January typically range from the upper teens in northern Maine to the middle 40s in southeastern Virginia.