AccuWeather.com reports in the Northeast and southern New England, the perfect pattern for fog, along with the warmth, continues through the week.

While the late summer into early fall is the prime season for fog, under the right conditions, fog can be a problem in the early spring as well.

Folks in parts of the Northeast have certainly received an education on this in recent days.

According to AccuWeather.com’s Chief Operating Officer Evan Myers, “The pattern is very similar to what occurs in September, in terms of the long nights, moisture and temperature.”

“It’s a blend of radiation and advection fog in this case,” Myers added.

Radiation fog occurs when marginally moist air in place cools to its saturation point at night and is most common in the autumn.

Advection fog occurs when the cloud bank is pushed in from a particular area or it is caused by the flow of moist air over a cold surface, causing it to cool to its saturation point. Advection fog is most common in the spring and late-winter.

Backdoor fronts bearing advection fog and drizzle have spoiled many fine spring days in coastal New England and the mid-Atlantic over the years.

According to AccuWeather.com’s Chief Meteorologist Elliot Abrams, “While water and land temperatures are running much warmer than normal this year, they are still relatively cool when compared to the unusually warm air mass like we have around the region now.”

Light winds and a layer of warm air above the ground are preventing the fog from breaking up at a rapid pace during the midday hours in the current pattern.

The temperature inversion, as it is called, is also trapping pollutants near the ground.

Over the weekend, a slow-moving storm will drift to the Atlantic coast and will begin to stir the atmosphere over the region.

Until this storm passes and dry air mixes in from the west, fog problems will continue. As the storm itself affects the area with its own moisture and showers, problems with low visibility may not be limited to the late-night and early-morning hours.

Abrams quipped, “In the wake of the storm next week, once the fog is gone it won’t be mist (missed).”

By Alex Sosnowski, expert senior meteorologist for AccuWeather.com

Los Angeles is almost as famous for its choking smog—a haze of ground-level ozone and particulate pollution that can aggravate asthma and other respiratory problems—as for its Hollywood stars. The reason so much smog forms there is because the city is in a low basin surrounded by mountains, with millions of cars and industrial sites spewing emissions into the air.

But thanks to tougher state and federal air quality standards, L.A. residents can breathe easier than they’ve been able to for decades. According to the non-profit Environment California, air pollution from cars and trucks across the state has decreased since the 1970s by more than 85 percent, with peak smog levels in the city of Los Angeles itself dropping some 70 percent. Meanwhile, California’s South Coast Air Quality Management District (AQMD) has been tracking smog levels in the area since 1976, and reports the number of ozone advisories—where residents are advised to stay indoors due to unhealthy local accumulations of smog—fell from a high of 184 days in 1977 to between zero and a few days a year now.

Tougher state and federal air quality standards, combined with cleaner burning engines on new vehicles today, have cut air pollution from cars and trucks across California by more than 85 percent since the 1970s, with peak smog levels in the city of Los Angeles dropping some 70 percent. (Thinkstock)

“California’s efforts to reduce air pollution from cars and trucks have made the state’s air cleaner than it has been in decades and Californians are healthier as a result,” says Bernadette Del Chiaro, Environment California’s clean energy advocate. This is especially notable because the number of miles driven in California doubled since the 1970s even though emissions significantly dropped—meaning that vehicles have gotten considerably more fuel efficient over the years. “The technologies found on new car lots today were practically unimaginable even 20 years ago, much less 40 years ago,” adds Del Chiaro. “Yet thanks to strong policies, California has pushed the auto industry to innovate and engineer a greener, cleaner car.”

According to Environment California’s research, a typical new car today is more than 99 percent cleaner burning than its 1960s counterpart. An older car produces about a ton of smog-forming pollution every 100,000 miles; a new car generates only 10 pounds over the same distance. This improvement saves consumers money at the pump as well as health care expenses and lives due to reduced pollution loads. And a new generation of hybrid and electric cars is driving automotive efficiency to even newer heights.

Updated federal air quality standards implemented in 2008 have also helped reduce ozone alert days in California and elsewhere. But despite this progress, environmental and public health advocates are urging federal lawmakers to raise air quality standards even higher. The goal is to get ground level ozone, a chief contributor to smog, no more prevalent than the range of 60-70 parts per billion averaged over eight hours, as unanimously recommended by an independent board of air experts and scientists created under the Clean Air Act to provide periodic review and recommendations on air quality standards.

The Obama administration reportedly considered updating the 2008 standard last summer but decided to table the decision until 2013 given economic priorities. Let’s hope that the economy turns around enough in the meantime so that industry won’t push back too hard against raising the federal standards.

CONTACTS: Environment California, www.environmentcalifornia.org; AQMD, www.aqmd.gov.

I got stuck with a weather story on Tuesday at the Boston Globe.

I actually really like writing about the weather, and I love weather maps and statistics and even lightening storms.

But I wasn’t prepared for the response I’d get for a simple story about advection fog rolling over Boston on Tuesday.

There were emails about conspiracy theories — people thought the government was sending Swine Flu through the fog. There were emails calling my an idiot, telling me to get a real job and write about real things. There were references about Kennedy flatulence. And there were cool emails with photos.

Here are the photos.