The temperature at BWI-Marshall Airport reached 91 degrees Tuesday, setting a record for the most 90-degree days in a calendar year and topping off more than eight months of weather extremes in Maryland.
Since last winter's blizzards and record accumulations, 2010 has brought drought, crop losses, rising numbers of heat-related deaths and the hottest summer on record for Baltimore.
Many of these events can be traced to natural climate variability, enhanced by the influence of global warming, according to Kevin Trenberth, head of the climate analysis section at the National Center for Atmospheric Research in Boulder, Colo.
"Global warming is not the major factor, but it is a nontrivial factor," Trenberth said. "We can say that these [extreme] events very likely would not have happened without global warming."
The heat has been especially costly for Maryland.
The Maryland Department of Health and Mental Hygiene on Tuesday reported two more heat-related deaths, bringing the total this year to 28. It is the highest count since 2006, but well below the record of 48 deaths in 2005.
Health officials said both individuals had underlying health conditions, and both were found in un-air-conditioned homes where temperatures had climbed to more than 90 degrees. One was an adult in Dorchester County, the other a senior in Baltimore.
Meanwhile, drought conditions in Central Maryland earlier this summer, and drought that persists in Western Maryland, Southern Maryland and the Lower Eastern Shore, have resulted in significant crop losses. Gov. Martin O'Malley asked the U.S. Department of Agriculture last month to consider the entire state for designation as an agricultural disaster area.
State Agriculture Secretary Earl "Buddy" Hance said, "I've farmed all my life, and this looks to be the worst year we've ever had."
Corn losses in Southern Maryland, where he farms, are estimated at 70 percent, he said. "If we can get the rain very quickly, we could salvage the soybean crop, but these hot, windy days aren't helping us."
Vegetable crops, accelerated by the heat, have come in so much earlier than usual that supplies are growing short, Hance said. And withered pastures are forcing livestock producers to buy more hay to feed their animals now and get them through the winter. That has added costs and shortened supplies.
And fields in many areas are "hard as a rock," threatening to frustrate farmers trying to plant winter wheat and barley if rain remains scarce.
As if heat and drought weren't enough, the National Weather Service forecast office in Sterling, Va., posted a Fire Weather Watch for Wednesday in most of Maryland west of the Chesapeake, as dry weather and a windy cold front raise the dangers of spreading wildfires.
Not everyone has hated the weather this year. Inside a Harborplace pavilion, Shan Howard, 27, of Baltimore, said the heat hasn't really affected him. He liked the snow, too.
"I enjoyed it because it was a long time since we got snow," he said. "But it was a lot," saying that one night he had to walk six miles home from work because buses weren't running. "Warmer days are fine," he added. "I went to Ocean City." He also has a friend with a pool.
But Tyreese Smith, 24, also of Baltimore, is looking forward to fall for the fashion — long boots, leggings and sweaters. In this kind of heat, and in last winter's snow, she said, "it's best just to stay inside." Luckily, her utilities are included in the heat. "I live in the house."
Not far away, Blake Wideman, 21, was cooling himself in the shade of an awning on Calvert Street. He's had enough of the heat. He likes to jog, but all summer the heat has been overwhelming. "Even at night it's hot."
The bad weather got a running start from the Dec. 18-19 blizzard that dropped 18 inches of snow at the airport, and more in other locations. An El Nino pattern contributed by sending repeated storms across the southern United States and up the East Coast, Trenberth said. Cold air injected by atmospheric patterns over the North Atlantic did the rest.
Back-to-back snowstorms piled up 25 inches on Feb. 5-6, and another 19.5 inches just three days later. The final February total, 50 inches, was a record for any month in Baltimore, besting the previous snowiest February, only seven years ago, which saw 40.5 inches.
And the season's total, 77 inches, was the most snow for Baltimore in any winter since the first official snow records were kept in 1883. The runner-up winter was 1995-1996, when 62.5 inches was recorded.
(The long-range forecast from the National Weather Service shows no clear trend either way for this winter's precipitation or temperatures. AccuWeather.com is predicting an average winter for Maryland.)
As snowy as it was, the winter was not extraordinarily cold. January 2010 was a bit warmer than average, but February was persistently cold, ending 4.6 degrees colder than the norm.