Cold Air

You needn't worry about cold air damaging your lungs when you exercise in cold weather. The only reports of lung damage from cold air are in people who were unable to get out of the cold, such as American gunners who lay unconscious in the frozen turrets of high-flying World War II bombers or people who were injured in automobile accidents and lay unconscious for hours in the cold.During exercise, your muscles produce so much heat that air inhaled at 40 degrees below zero will be warmed more than 100 degrees before it reaches your lungs.

Forecasters are watching another possible mess of a light wintry mix on Friday. As the window for a big snowfall narrows, though, at least one forecaster still sees favorable snow chances in the weeks ahead. Meteorologists are watching two key climate patterns that influence storm tracks, and Friday, they are expected to butt heads, helping to keep the forecast for Maryland tricky. One indicator known as the North Atlantic Oscillation, known for sending monster snowstorms up the East Coast, is helping push some precipitation through the area.

If you like frigid air, deep snow and icy ponds, that was one disappointing January. But if you stretch to pay the heating bills and fear getting around on snow and ice, the month just ended in Baltimore was a blessing - mild, even balmy at times, and snow-free. And you're probably praying your good fortune carries over into February. Forget it. "There are certain changes ahead," said Mike Halpert, a meteorologist at the national Climate Prediction Center in Camp Springs. "Week 2 [of February]

Havre de Grace Mayor Wayne Dougherty led the way. He raised the most money. And he was the best dressed. So at the appointed hour - 10 a.m. Saturday - the mayor and dozens of others, including Scotty Hurst, Chief of the Susquehanna Hose Co., ran, walked, waddled and squealed into the Chesapeake Bay for the second annual Havre de Grace Duck Dunk. It's a fundraiser for the Havre de Grace volunteer fire company similar to the Polar Bear Plunge, Maryland's huge winter fundraiser to benefit the Special Olympics.

OK, class, put away your books and get out your pencils. This is a quiz. It's not a difficult one, but your answers may determine whether you can be comfortable in your old, un-centrally air-conditioned house this summer. Here goes:1. Hot air _____. (Fill in the blank.)2. Cold air _____. (Fill in the blank.)Well, we said it wasn't hard. If you said "rises" for 1. and "falls" for 2., give yourself a nice, cold glass of your favorite soft drink.While it's true that virtually everybody knows these simple physical laws, not everyone knows how to use them to vastly increase the comfort level of a home during hot weather.

Sleet fell in the Baltimore metropolitan area yesterday, arriving in the afternoon on blasts of cold air pouring into the Chesapeake region from the north and northwest. The precipitation was expected to end this afternoon, according to the National Weather Service.Jim Wiesmueller, a weather service forecaster in Sterling, Va., said moisture from the southwestern part of the country mixed with the cold air to create "ice pellets," or sleet.Temperatures were just below 40 degrees at rush hour last night, Wiesmueller said.

Will Baltimore ever get a decent snowfall? Some forecasters believe they're seeing a shift in continental weather patterns that could send more storms our way, starting next week. We'll be sandwiched between cold air to the north and moist air to the south. Storms tracking eastward along the boundary will throw the wet air into the cold, making snow and ice. Kids! Pajamas inside-out!

The main thing you need to retrofit central air conditioning is a deep desire for it.Even in a gut rehab, central air ductwork can be obtrusive and play havoc with a design.There are three areas where problems arise:* Air supply. A truly efficient air-conditioning system needs a lot of ductwork. Generally, each room needs at least one air supply, or outlet. Most supplies feed from the basement trunk line, with a separate duct all the way up for each one. (It is possible to feed more than one supply by installing trunk lines at each floor, but it requires chases and bulkheads.

The robins were casting their votes by first light today.Bring on spring, they seemed to be whistling.The crocuses are emerging, too, trying to stand up and be counted.It's Election Day, and the early returns are decisive: Out with ice on the windshield and winter wardrobes. In with longer, sunnier days and shirt-sleeves.However, weather pundits, analyzing these early returns, aren't promising that happy days are here again. Not yet.But they are saying it will be pleasantly warm through the weekend, if a bit wet.In central and eastern Maryland, temperatures are expected to reach the high 50s or low 60s. Lows will be in the upper 30s and low 40s."

The snowstorm that pummeled Maryland yesterday was first spotted by weather forecasters late last week when it came in off the Pacific Ocean and produced weekend showers in Los Angeles. With plenty of time to watch the conditions develop - and close agreement among the computer models they use to predict weather behavior - forecasters were on the money this week as the season's first big winter storm struck the Northeast. "They had a choice: to go with the models or go out on their own. The consistency of the models gave them high confidence, and they went in the right direction," said James Hoke, director of the federal Hydrometeorological Prediction Center in Camp Springs.

A springlike weekend with temperatures approaching 70 degrees is ahead, but forecasters are hypothesizing Arctic air could dip southward to push the mercury below normal late in the month. Temperatures are forecast to reach 60 degrees or higher three days in a row, Saturday through Monday, without a chance for showers until Monday evening. While that warmth is about 20 degrees above normal, it isn't all that rare. The last time BWI Marshall Airport did not break 60 degrees at some point in January was 2009.

Will Baltimore ever get a decent snowfall? Some forecasters believe they're seeing a shift in continental weather patterns that could send more storms our way, starting next week. We'll be sandwiched between cold air to the north and moist air to the south. Storms tracking eastward along the boundary will throw the wet air into the cold, making snow and ice. Kids! Pajamas inside-out!

If you like frigid air, deep snow and icy ponds, that was one disappointing January. But if you stretch to pay the heating bills and fear getting around on snow and ice, the month just ended in Baltimore was a blessing - mild, even balmy at times, and snow-free. And you're probably praying your good fortune carries over into February. Forget it. "There are certain changes ahead," said Mike Halpert, a meteorologist at the national Climate Prediction Center in Camp Springs. "Week 2 [of February]

Temperatures dropped 20 degrees in three hours yesterday afternoon in the Baltimore area and headed toward freezing as a powerful cold front barreled across the state with rain and gusty winds, ushering in the coldest weather of autumn. The mercury topped out at 75 at Baltimore-Washington International Thurgood Marshall Airport, just one degree shy of the record for the date set in 1928. The highest temperature we can hope for today will be in the low 40s, forecasters said. "That's a big change," said Steven M. Zubrick, science and operations officer for the National Weather Service forecast office in Sterling, Va. "Somebody who walks out and thinks they're ... . not going to wear a coat, they're going to be very surprised."

Wintry conditions returned to Maryland today after yesterday's springlike temperatures, as morning rain gave way to light snow when a front brought with it a blustery, cold air mass. The snow tapered off by midday, and the National Weather Service in Sterling, Va., canceled its earlier snow advisory. By 3 p.m., a wind advisory for the region had also been canceled. A cold front that moved into the Mid-Atlantic region forced temperatures to plummet from a high of near 50 degrees early in the day. At 2 p.m., Baltimore-Washington International Airport registered a high of 28 degrees, but the wind chill made it feel more like 15. Forecasters called for the storm to produce from 1 to 2 inches of accumulation, mainly over grassy areas.

The three-day Presidents Day weekend storm in Maryland had its origins in a Pacific rainstorm that soaked the Los Angeles area with torrential rains, then crossed the country and collided with stubborn arctic air entrenched across the Northeast. Its legacy will likely be the biggest snowstorm in Baltimore in more than seven years, weather experts said, with total accumulations that might rival some of the deepest snowfalls in the city's history. "I would say we're destined here for the top five, and we've got a good shot at the top three," said Todd Miner, a meteorologist with Penn State Weather Communications.