Heat wave to roast Northeast as temps forecast to approach 100 F
By
Alex Sosnowski, AccuWeather senior meteorologist
Published Jul 17, 2020 3:34 PM EDT
The hottest weather of the summer is poised to swelter many areas of the mid-Atlantic, central Appalachians and southwestern and central New England into the first part of the week. In addition to heat advisories being in effect across the Midwest, excessive heat watches were issued for Philadelphia and the surrounding area.
A portion of the same weather system, a large area of high pressure, that broiled the south-central United States much of last week will continue to poke northeastward in the coming days.
Actual temperatures are forecast to rise well into the 90s F from Pennsylvania, New York state, Vermont, Connecticut, Rhode Island, New Hampshire, Massachusetts, West Virginia, New Jersey, Maryland, Delaware, and Virginia.
A few locations over the mid-Atlantic can reach or exceed 100 degrees for a couple of hours in the afternoon on Monday.
CLICK HERE FOR THE FREE ACCUWEATHER APP
AccuWeather RealFeel® Temperatures will be several degrees higher than the actual temperature. The RealFeel® Temperature not only takes into consideration the temperature and humidity but also sunshine, any breeze and other factors that provide a true representation of how hot the air feels on the human body.
Daily records that have stood since the 1930s and even near the turn of the 20th century will be challenged.
On Sunday, Washington D.C. the temperature flirted with the one hundred degree mark, but landed just a few degrees short of the daily record high of 102 from 1930. Farther south, Norfolk, Virginia, soared to 102 degrees on Sunday and toppled the previous record of 101 last set in 1942.
In Philadelphia and Baltimore, the records on Monday of 99 and 102, respectively, were also set in 1930.
A heat wave is generally defined as a stretch of 90-degree-Fahrenheit (or higher) temperatures for at least three days in a row over the northern U.S.
The conditions may cause some cities to be dangerously hot around the clock for a several-day stretch. This phenomenon, known as the 'urban heat island effect,' comes into play as the concrete and brick buildings begin to finally cool near daybreak, just as the new day will be getting underway.
People are urged to seek air-conditioned environments where possible and to drink plenty of non-alcoholic and non-caffeinated fluids as alcohol and caffeine can accelerate the dehydration process.
Meteorologists recommend avoiding strenuous physical labor or exercise during the late morning, afternoon and early evening hours when air temperatures climb to the highest levels of the day.
A 20-day streak of temperatures hitting 90 or higher in Washington, D.C., just came to an end on Wednesday -- just one day shy of tying the longest stretch of 90-degrees days on record (set in 1980 and tied in 1988). The high was held to 87 on Thursday due to persistent cloud cover and a breeze off the slightly cooler waters of the Potomac River. The highest temperature at Reagan National Airport during the brutal stretch was 97 on July 3. A new stretch of 90-degree weather commenced on Friday afternoon.
So far, this summer's high in New York City was 96 set on July 6. Temperatures on Monday may challenge this mark.
Farther north, the heat wave which spanned June 18-23 may be tough to surpass, but even so, conditions will still be very warm. Even over the mountains in the region, the uniformly hot air mass will allow little relief, except for a cool lake, stream or pool.
How hot the weather will get in eastern New England is a bit more tricky as a sea breeze may step in to mitigate temperatures, including around Boston. Still, temperatures are forecast to approach 90 on Monday.
The hot air is likely to be felt on most beaches from New Jersey to Delaware, Maryland and Virginia.
The combination of a slight dip in the jet stream and a weak push of slightly cooler air may be enough to keep high temperatures in the 80s for the middle and latter parts of the week around the eastern Great Lakes, eastern Ohio Valley, central Appalachians and portions of New England.
At least spotty thunderstorm activity is forecast to accompany the slight shift in the jet stream and proximity of surface fronts. Just as a dry landscape functions more like a desert with a rapid rise in temperature during the day, a wet landscape requires more of the sun's energy being used to evaporate moisture, rather than heating the ground and adjacent air. For this reason, it is much easier for temperatures to surge when the ground is dry as opposed to when the ground is wet.
Along the mid-Atlantic coast, even though temperatures may be trimmed a few degrees later this week after rounds of thunderstorms, highs are still likely to be at or above 90 in most cases. A slight cooling sea breeze may be more active during the middle and latter parts of the week on the beaches, as opposed to the start of the week.
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
Heat wave to roast Northeast as temps forecast to approach 100 F
By Alex Sosnowski, AccuWeather senior meteorologist
Published Jul 17, 2020 3:34 PM EDT
The hottest weather of the summer is poised to swelter many areas of the mid-Atlantic, central Appalachians and southwestern and central New England into the first part of the week. In addition to heat advisories being in effect across the Midwest, excessive heat watches were issued for Philadelphia and the surrounding area.
A portion of the same weather system, a large area of high pressure, that broiled the south-central United States much of last week will continue to poke northeastward in the coming days.
Actual temperatures are forecast to rise well into the 90s F from Pennsylvania, New York state, Vermont, Connecticut, Rhode Island, New Hampshire, Massachusetts, West Virginia, New Jersey, Maryland, Delaware, and Virginia.
A few locations over the mid-Atlantic can reach or exceed 100 degrees for a couple of hours in the afternoon on Monday.
CLICK HERE FOR THE FREE ACCUWEATHER APP
AccuWeather RealFeel® Temperatures will be several degrees higher than the actual temperature. The RealFeel® Temperature not only takes into consideration the temperature and humidity but also sunshine, any breeze and other factors that provide a true representation of how hot the air feels on the human body.
Daily records that have stood since the 1930s and even near the turn of the 20th century will be challenged.
On Sunday, Washington D.C. the temperature flirted with the one hundred degree mark, but landed just a few degrees short of the daily record high of 102 from 1930. Farther south, Norfolk, Virginia, soared to 102 degrees on Sunday and toppled the previous record of 101 last set in 1942.
In Philadelphia and Baltimore, the records on Monday of 99 and 102, respectively, were also set in 1930.
A heat wave is generally defined as a stretch of 90-degree-Fahrenheit (or higher) temperatures for at least three days in a row over the northern U.S.
The conditions may cause some cities to be dangerously hot around the clock for a several-day stretch. This phenomenon, known as the 'urban heat island effect,' comes into play as the concrete and brick buildings begin to finally cool near daybreak, just as the new day will be getting underway.
People are urged to seek air-conditioned environments where possible and to drink plenty of non-alcoholic and non-caffeinated fluids as alcohol and caffeine can accelerate the dehydration process.
Meteorologists recommend avoiding strenuous physical labor or exercise during the late morning, afternoon and early evening hours when air temperatures climb to the highest levels of the day.
Related:
A 20-day streak of temperatures hitting 90 or higher in Washington, D.C., just came to an end on Wednesday -- just one day shy of tying the longest stretch of 90-degrees days on record (set in 1980 and tied in 1988). The high was held to 87 on Thursday due to persistent cloud cover and a breeze off the slightly cooler waters of the Potomac River. The highest temperature at Reagan National Airport during the brutal stretch was 97 on July 3. A new stretch of 90-degree weather commenced on Friday afternoon.
So far, this summer's high in New York City was 96 set on July 6. Temperatures on Monday may challenge this mark.
Farther north, the heat wave which spanned June 18-23 may be tough to surpass, but even so, conditions will still be very warm. Even over the mountains in the region, the uniformly hot air mass will allow little relief, except for a cool lake, stream or pool.
How hot the weather will get in eastern New England is a bit more tricky as a sea breeze may step in to mitigate temperatures, including around Boston. Still, temperatures are forecast to approach 90 on Monday.
The hot air is likely to be felt on most beaches from New Jersey to Delaware, Maryland and Virginia.
The combination of a slight dip in the jet stream and a weak push of slightly cooler air may be enough to keep high temperatures in the 80s for the middle and latter parts of the week around the eastern Great Lakes, eastern Ohio Valley, central Appalachians and portions of New England.
At least spotty thunderstorm activity is forecast to accompany the slight shift in the jet stream and proximity of surface fronts. Just as a dry landscape functions more like a desert with a rapid rise in temperature during the day, a wet landscape requires more of the sun's energy being used to evaporate moisture, rather than heating the ground and adjacent air. For this reason, it is much easier for temperatures to surge when the ground is dry as opposed to when the ground is wet.
Along the mid-Atlantic coast, even though temperatures may be trimmed a few degrees later this week after rounds of thunderstorms, highs are still likely to be at or above 90 in most cases. A slight cooling sea breeze may be more active during the middle and latter parts of the week on the beaches, as opposed to the start of the week.
Keep checking back on AccuWeather.com and stay tuned to the AccuWeather Network on DirecTV, Frontier and Verizon Fios.
Report a Typo