As summer settles into Boston, residents are increasingly feeling the impact of a thick wall of humidity stretching across the region.
With already two heat waves this season, Boston is on track for one of its most humid summers on record.
The rising temperatures are accompanied by an unusually high level of mugginess, leading to conditions that many are finding uncomfortable and oppressive.
According to meteorological experts, climate change is causing the atmosphere to warm, enabling it to hold more moisture.
As a result, Bostonians are experiencing more tropical days, frequent storms, and a heightened vulnerability to extreme weather events.
A significant example occurred recently with Thursday morning’s severe rainstorm, which dumped 4 to 6 inches of rain, leading to road closures and stranded vehicles on I-93.
This pattern is likely to continue, as summers are becoming not only hotter but also wetter, with predictions of increased snowfall in the winter months.
An important measurement here is the dew point, which indicates the amount of moisture in the air.
High dew points create a sticky and uncomfortable atmosphere, making it harder for the human body to cool itself through sweating.
Data from Logan Airport shows alarming trends in dew point averages since records began in 1936.
During the first 50 days of this summer, daily dew points across Greater Boston were above average, a trend that has steadily risen over the past few decades.
The implications of increased humidity go beyond mere discomfort; they pose serious health risks related to extreme heat.
High dew points hinder the body’s natural cooling process, thus increasing the potential for heat-related illnesses.
Moreover, elevated dew points can intensify severe thunderstorms, creating more significant rainfall potential.
Historically speaking, the average daily dew point in Boston has hovered around 60 degrees, a threshold where noticeable humidity begins altering comfort levels.
Here, bodies start exerting more effort to sweat due to the high moisture content, with evaporation taking longer, further complicating the cooling mechanism.
Current readings for June and early July have exceeded this average by over 2.7 degrees, suggesting a trajectory toward Boston experiencing one of its top three muggiest summers should this trend persist.
Across New England, a similar pattern has emerged, with many regional airports reporting above-average dew points for the last five summers.
Interestingly, the peak period for dew point temperatures typically occurs from mid-July through the first half of August, meaning that the challenge of high humidity is far from over.
Notably, Boston has seen the number of summer days with dew points reaching 70 degrees double since the mid-1980s, escalating from around 20 days to nearly 40 days.
The increased dew points are indicative of a warming atmosphere, contributing to an uptick in severe storms and a growing population of moisture-loving insects like ticks and mosquitoes.
Meteorological analysis points to a change in the jet stream’s trajectory that has allowed for a more consistent southerly airflow, which draws moisture from the Southeast and Gulf Stream into the region.
This summer, a robust Bermuda high pressure system positioned off the East Coast has intensified this moisture influx, leading to persistently high humidity.
This situation creates a dual effect: hotter days combined with elevated nighttime temperatures meaning that cooling doesn’t come easy.
Higher moisture levels add energy to the atmosphere, raising the likelihood of severe thunderstorms when a cold front moves through.
As the summer unfolds, experts anticipate continued high humidity levels, comparing Boston’s climate to that of traditionally more humid cities like Washington, D.C., and Baltimore.
With at least half of the summer ahead, observers are both intrigued and concerned about how this evolving weather pattern will affect Boston and its residents.
The findings underscore the urgent need to address the broader implications of climate change on regional weather and living conditions.
Ken Mahan, the author, can be reached for further insights.
image source from：bostonglobe
