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Philly’s dry January (no, not that kind) has kept snow from melting and led to flaky skin

The ultra-air has inhibited melting, and it has been mighty windy, with 15 days so far with gusts past 30 mph.

Daliah Legenski (left) and her mother, Michele (right), of Durning String Band, battle the wind along Broad Street on New Year's Day, the beginning of what has been a very windy and bone-dry month.
Daliah Legenski (left) and her mother, Michele (right), of Durning String Band, battle the wind along Broad Street on New Year's Day, the beginning of what has been a very windy and bone-dry month.Read moreDavid Maialetti / Staff Photographer

It would be understandable if you failed to recognize the liquid due to fall from the skies on Friday. It’s a harmless substance called rain.

And not only has rain been mighty scarce in the early going of 2025, the atmosphere overall has been moisture-starved, something that dermatologist Khanh Thieu doesn’t need a hygrometer to verify.

“I’ve had a lot of patients come in and complain their skin is more itchy,” he said. Added Thieu, who is chief of dermatology for Main Line Health, and who happens to suffer from eczema: “The last few weeks I’ve been moisturizing several times a day.”

Said New Jersey state climatologist David Robinson: “Lots of ChapStick likely used this month!”

In terms of absolute moisture in the atmosphere, this has been one of the drier Januaries in the period of record, an Inquirer analysis showed. That helps explain the itchy skin — along with the tenacity of that tired, meringued snowpack that had covered much of the region since mid-month, despite highs above freezing on several days.

It has also been a month of drying winds from west and northwest, with Wednesday being the 15th day this month that gusts have exceeded 30 mph.

How dry has the air been in Philly this month?

Through Wednesday, officially 0.39 inches of precipitation had been measured at Philadelphia International Airport, and most of that was the result of 4.6 inches of melted snow. An inch of rain is expected Friday, and that would spoil Philly’s shot at the January record for lowest precipitation, 0.45, set in 1955.

The air, itself, also has been exceptionally dry, based on an analysis of dew points, which measure the absolute moisture content of the air. “Humidity” is a more popular measure, but it is relative to the amount of moisture the air can hold at a certain temperature. Hot air can hold a whole lot more moisture than cold.

The dew point is the temperature at which vapor condenses and comes out of hiding, as it does with the morning dew as the air cools. The average dew point temperature this month through Wednesday was about 15, several degrees below normal, ranking this among the driest Januaries in the last 50 years.

During January 2024, which Thieu said was relatively itch-free for him, the dew point was five degrees above average.

When it’s cold and dry like this, the skin has a hard time retaining moisture, leading to irritating cracking and itching.

The dryness also has contributed to the snow’s staying power, meteorologists said. Moist air promotes melting. When water vapor comes in contact with snow and ice, it condenses and gives off latent heat. That can make snow disappear faster than a computer-model run.

What does moisture in the air have to do with the snow cover?

A classic example of high dew point melting occurred in January 1996, after the city’s record 30.7-inch snowfall on the 7th and 8th, which was taking its time melting with a sequence of chilly days and a lame winter sun.

Early on the morning of Jan. 19, the dew point surged to 60 degrees in the early morning as a light rain began, and what was a prodigious snowpack was erased in a matter of hours. According to Nolan Doesken, the former longtime Colorado state climatologist and an expert on melting, the surging moisture-laden air had far more to do with the vanishing than the modest rains.

Only about 0.8 inches fell that day, the bulk of that in the afternoon, but the snowmelt set off widespread and destructive flooding.

January also has been a windy month in the region

Winds have helped erase some of the snow cover by promoting “sublimation,” meteorologists said, in which snow changes state and returns to the atmosphere as water vapor.

January has been quite windy in the region, with gusts past 30 mph at Philadelphia International Airport on 15 different days.

Robinson, a Rutgers University professor who is the nation’s longest-serving state climatologist, said that in the first 11 days of the month, at least one of his stations across New Jersey reported gusts past 40 mph, “a run I can’t recall seeing before.”

When will all the snow be gone, and when might snow return?

If it hasn’t happened already, bare ground is likely to appear soon near you.

Temperatures and dew points are forecast to rise well into the 40s on Friday afternoon in the rain.

As for the prospects of accumulating snow in the near future, let’s just say: May the Eagles fans fare better than the snow fans.

And foreshadowing the groundhog’s big day, the National Oceanic and Atmospheric Administration’s Climate Prediction Center sees the chances favoring a warmer-than-normal February.