'Ghost of Delta,' other factors unleash soaking rain in northeastern US
By
Alex Sosnowski, AccuWeather senior meteorologist
Published Oct 12, 2020 3:17 PM EDT
|
Updated Oct 13, 2020 1:27 PM EDT
Rain that began soaking part of the northeastern United States late in the weekend will continue into Tuesday evening in eastern New England and could lead to slick travel conditions along with minor flooding issues.
The rain will be beneficial for drought areas but could become problematic for coastal locations that have picked up a surplus of rainfall since the start of the summer. Several weather factors are behind the rain dampening the region with the barely noticeable circulation and moisture from Delta being only a small part of the equation. Delta all but broke up while trying to cross the southern Appalachians over the weekend.
"What has been persevered with the ghost of Delta is a batch of tropical moisture that will continue to intermingle with fresh moisture from the western Atlantic," according to AccuWeather Meteorologist Matt Benz.
"Other goings on with the wet setup include that the warmer, moist air to the south will be forced to rise slowly over the dome of cool air over the Northeast, which meteorologists call overrunning," Benz explained. This overrunning process is the main cause of widespread clouds and precipitation during the autumn, winter and spring.
Enough rain could fall with the setup to cause travel delays and minor flooding in major cities along the I-95 corridor.
A large swath of clouds extended from the Midwest to off the Atlantic coast of the Northeast on Monday morning, Oct.12, 2020. (CIRA at Colorado State/GOES-East)
Farther inland over the central Appalachians and especially over New England, where leaves are coming down, roads can be especially slick from the fallen leaves and rain. Motorists and pedestrians should use caution in any wooded area where leaves may be starting to fall, when combined with the rain. The leaves could also block storm drains, adding to localized flooding concerns.
The wet weather will not only put a damper on outdoor plans and slow commutes in general but could also hinder construction and agricultural operations during harvesting time as fields are prepped for winter.
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The bulk of the rain left northern Virginia early Monday but may linger in New York City into Tuesday morning's commute and may persist much of the day in Boston.
"A cold front approaching from the Midwest will enhance some of the rain farther inland over the central Appalachians to the eastern Great Lakes area and northwestern New England into Tuesday," Benz added.
The cold front from the Midwest will help to kick the rain out of the way, but the same system could bring a period of downpours to the central Appalachians from West Virginia to western Pennsylvania to western and central New York state later Monday night to Tuesday morning.
The rain into Tuesday evening will be tremendously beneficial in New England where long-term drought conditions range from moderate to extreme. A general 1-3 inches of rain is forecast from the wet weather. Even lesser rainfall on the order of 0.25 to 0.75 of an inch will help with abnormally dry to severe drought conditions in western and central Pennsylvania to western, central and northern New York state.
Nearly 2 inches of rain had fallen in Richmond, Virginia, and 1.30 inches on Atlantic City, New Jersey, by the mid-morning hours on Monday. New York City had picked up 0.28 of an inch with much more on the way.
Since June 1, rainfall has varied tremendously across the Northeast. In parts of New England, rain is about 10 inches below average or 50% of normal. In parts of the lower mid-Atlantic, rainfall is about 10 inches above normal or 150% of average.
Since the main thrust of cooler air behind the front will be across Canada, and sunshine is expected to return by midweek, so temperatures should rebound to mild levels for the middle of October.
But beware, a much stronger push of cooler air will be more successful at slashing temperatures later in the week.
Depending on the track of a storm along that strong front, heavy rain in coastal areas of New England and the mid-Atlantic could even end as accumulating snow over some the highest terrain of the Northeast this weekend.
Meteorologists warned that lake-effect mixed rain and wet snow can occur on not-so-high elevations of western New York and northwestern Pennsylvania.
Keep checking back on AccuWeather.com and stay tuned to the AccuWeather Network on DirecTV, Frontier and Verizon Fios.
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News / Weather Forecasts
'Ghost of Delta,' other factors unleash soaking rain in northeastern US
By Alex Sosnowski, AccuWeather senior meteorologist
Published Oct 12, 2020 3:17 PM EDT | Updated Oct 13, 2020 1:27 PM EDT
Rain that began soaking part of the northeastern United States late in the weekend will continue into Tuesday evening in eastern New England and could lead to slick travel conditions along with minor flooding issues.
The rain will be beneficial for drought areas but could become problematic for coastal locations that have picked up a surplus of rainfall since the start of the summer. Several weather factors are behind the rain dampening the region with the barely noticeable circulation and moisture from Delta being only a small part of the equation. Delta all but broke up while trying to cross the southern Appalachians over the weekend.
"What has been persevered with the ghost of Delta is a batch of tropical moisture that will continue to intermingle with fresh moisture from the western Atlantic," according to AccuWeather Meteorologist Matt Benz.
"Other goings on with the wet setup include that the warmer, moist air to the south will be forced to rise slowly over the dome of cool air over the Northeast, which meteorologists call overrunning," Benz explained. This overrunning process is the main cause of widespread clouds and precipitation during the autumn, winter and spring.
Enough rain could fall with the setup to cause travel delays and minor flooding in major cities along the I-95 corridor.
A large swath of clouds extended from the Midwest to off the Atlantic coast of the Northeast on Monday morning, Oct.12, 2020. (CIRA at Colorado State/GOES-East)
Farther inland over the central Appalachians and especially over New England, where leaves are coming down, roads can be especially slick from the fallen leaves and rain. Motorists and pedestrians should use caution in any wooded area where leaves may be starting to fall, when combined with the rain. The leaves could also block storm drains, adding to localized flooding concerns.
The wet weather will not only put a damper on outdoor plans and slow commutes in general but could also hinder construction and agricultural operations during harvesting time as fields are prepped for winter.
CLICK HERE FOR THE FREE ACCUWEATHER APP
The bulk of the rain left northern Virginia early Monday but may linger in New York City into Tuesday morning's commute and may persist much of the day in Boston.
"A cold front approaching from the Midwest will enhance some of the rain farther inland over the central Appalachians to the eastern Great Lakes area and northwestern New England into Tuesday," Benz added.
The cold front from the Midwest will help to kick the rain out of the way, but the same system could bring a period of downpours to the central Appalachians from West Virginia to western Pennsylvania to western and central New York state later Monday night to Tuesday morning.
The rain into Tuesday evening will be tremendously beneficial in New England where long-term drought conditions range from moderate to extreme. A general 1-3 inches of rain is forecast from the wet weather. Even lesser rainfall on the order of 0.25 to 0.75 of an inch will help with abnormally dry to severe drought conditions in western and central Pennsylvania to western, central and northern New York state.
Nearly 2 inches of rain had fallen in Richmond, Virginia, and 1.30 inches on Atlantic City, New Jersey, by the mid-morning hours on Monday. New York City had picked up 0.28 of an inch with much more on the way.
Since June 1, rainfall has varied tremendously across the Northeast. In parts of New England, rain is about 10 inches below average or 50% of normal. In parts of the lower mid-Atlantic, rainfall is about 10 inches above normal or 150% of average.
Since the main thrust of cooler air behind the front will be across Canada, and sunshine is expected to return by midweek, so temperatures should rebound to mild levels for the middle of October.
But beware, a much stronger push of cooler air will be more successful at slashing temperatures later in the week.
Related:
Depending on the track of a storm along that strong front, heavy rain in coastal areas of New England and the mid-Atlantic could even end as accumulating snow over some the highest terrain of the Northeast this weekend.
Meteorologists warned that lake-effect mixed rain and wet snow can occur on not-so-high elevations of western New York and northwestern Pennsylvania.
Keep checking back on AccuWeather.com and stay tuned to the AccuWeather Network on DirecTV, Frontier and Verizon Fios.
Report a Typo