Warm winter weather

The only clues that this is the first day of winter are the lack of leaves on the trees and the installation of holiday evergreens above Joseph Young and Amanda McCormick of Baltimore, who enjoy the Winter Solstice with an unofficial temperature in the 70s at Mount Vernon Place. (Karl Merton Ferron, Baltimore Sun / December 21, 2013)

People wore shorts and T-shirts all around Baltimore on Saturday as temperatures hit a record 70 degrees, with slightly higher temperatures expected Sunday.

Both the Inner Harbor and BWI Marshall Airport recorded highs of 70 degrees, while Annapolis hit 72 degrees, the National Weather Service reported.

The previous record high for the day at BWI was 62 degrees in 2011. A normal high is 44 degrees.

The warm weather came during the winter solstice, the "shortest" day of the year. Baltimore had nine hours and 24 minutes of daylight Saturday.

The actual solstice is the instant when the sun is the farthest south in the sky because of the Earth's tilted axis. This year, it occurred at 12:11 p.m. Saturday.

The Earth's axis tilts at a 23.5-degree angle, which is what brings the seasons; at the winter solstice, the North Pole is tilted farthest from the sun. At that moment, the Arctic circle is in 24-hour darkness, while Antarctica is in full sunlight.

The solstice marks the start of winter in the Northern Hemisphere. Although Saturday was the day with the least sunshine, the coldest weather typically lags behind the solstice by a month or two, with January and February, on average, being colder than December here.

For Sunday, the National Weather Service predicted scattered showers and a possible thunderstorm after 1 p.m., with temperatures again in the low 70s and overcast skies for the Ravens game at M&T Bank Stadium. The chance of precipitation was 60 percent, with a south wind blowing about 17 mph.

If temperatures reach that high on Sunday, they could eclipse the record of 70 degrees set on Dec. 22, 1889, according to National Weather Service meteorologist Dan Hoffman.

The warmth was caused by a persistent southwesterly wind pumping warm air into the region over the past two or three days, Hoffman said.

The Baltimore area could see showers and thunderstorms Sunday night, with rain likely after 1 a.m. Monday. Lows could hover about 58 degrees. Showers could linger into Monday before temperatures start falling again. Monday's high is expected to be about 60 degrees while temperatures will be in the lower 40s on Tuesday.

"Then we're back down to the mid-30s," Hoffman said.

Forecasters are predicting a high of about 34 degrees for Christmas.

Baltimore Sun reporter Scott Dance contributed to this article.

jgeorge@baltsun.com