The National Christmas Tree will light up at President's Park in Washington, D.C., amid clear, calm weather on Thursday night.
On the first day of the month, tens of thousands of people will gather near the White House to catch a glimpse of the First Family and several celebrity headliners.
Mild and rainy weather will plague the mid-Atlantic through Wednesday night, saturating lawns and sidewalks for Thursday.
The rain is expected to end on Wednesday night, allowing peeks of sun to sneak through as spectators arrive at the White House lawn throughout the day on Thursday.
"It will be nice and dry with a mainly clear sky thanks to an area of high pressure edging into the region," AccuWeather Meteorologist Steve D. Travis said.
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Cooler conditions are also expected to take over for Thursday, though high temperatures will remain well above the seasonal average of 52 F.
High temperatures will drop from the low 70s on Wednesday to around 60 F on Thursday in the nation's capital.
"For anyone heading out early for the lighting, temperatures will generally be in the middle to upper 50s late in the afternoon," Travis said.
Those arriving early to the event will therefore be able to forgo the hats and winter jackets, at least during the afternoon.
Temperatures are expected to fall quickly after sunset (which takes place at 4:45 p.m. EST), though it will be an unseasonably mild evening.
By the time the tree lights up at 7:00 p.m. EST, temperatures will fall into the lower 50s.
Light winds will bring RealFeel® Temperatures down into the upper 40s F.
Anyone planning to attend the event after dark should prepare for the chill with coats, hats and gloves despite the mild afternoon weather.
Temperatures will continue to fall through the night, becoming increasingly chilly as performers including Kelly Clarkson, James Taylor and Garth Brooks take the stage.
Story written by AccuWeather Meteorologist Faith Eherts.