Much higher temperatures are on the way to Philadelphia. The warmth will be accompanied by spotty rain and patchy fog at times.
Record-challenging warmth is possible on Sunday with temperatures surging close to 70 degrees.
As warmer, more moist air moves in, episodes of fog are possible which could slow travel.
Heavy rain will stay north and west of Philadelphia through the day Sunday.
According to AccuWeather.com Long Range Expert Paul Pastelok, "With the anticipated weather now through the end of the month, temperatures for December may average close to normal."
As of Dec. 18, temperatures have averaged 2.5 degrees below the normal of 39.3 degrees for the month to date.
Pastelok expects the weather pattern to erase much of this local temperature deficit by the end of the month with well above-average warmth forecast late this week into the weekend.
"There will still be a few chilly episodes later in the month, but not to the extreme of what we have experienced during late November into early December," Pastelok stated.
The warmup will not mean an end to snowstorms for the upcoming winter.
Tune in to AccuWeather Live Mornings every weekday at 7 a.m. EST. We will be talking about the snowstorm and weather leading up to Christmas.
Monday is shaping up to be Philadelphia's warmest day so far this year, kicking off a week that will be dominated by summer warmth.
Monday is shaping up to be New York City's warmest day so far this year, kicking off a week that will be dominated by summer warmth.
Early indications suggest that the first tropical system of 2015 could spin up off the southern Atlantic Coast of the United States this week.
After a cooler-than-normal summer 2014, the Northeast can anticipate more 90-degree days. Meanwhile, drought conditions will expand in the West.
Parts of this week will feel more like summer across the Midwest and Northeast with the warmest days of 2015 set to unfold.
Thunderstorms are set to return to the Plains for the first week of May following a relatively quiet end to April.
Eastern U.S. (1812)
May snowstorm swept from Philadelphia northeastward to Maine. Snow covered ground in New York City; 12" accumulated near Keene, New Hampshire, 9" fell at Waltham, Mass., near Boston.
Severe snowstorm: 33.8" in Havre (24.8 inches of which fell in 24 hours).
New Orleans, LA (1978)
Persistent thunderstorms caused worst flooding in 30 years at New Orleans; lightning ignited an oil storage tank at Covent, LA.