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April 2021 nor'easter

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April 2021 nor'easter
NASA satellite imagery of the nor'easter near peak intensity over Cape Cod at 18:58 UTC (2:58 p.m. EDT) on April 16
TypeExtratropical cyclone
Nor'easter
Winter storm
FormedApril 14, 2021
DissipatedApril 20, 2021
(Exited to sea on April 17, 2021)
Highest winds
Highest gust68 mph (109 km/h) at Mount Washington, New Hampshire[1]
Lowest pressure988 mb (29.18 inHg)
Maximum snowfall
or ice accretion
Snow – 14 in (36 cm) at Lempster, New Hampshire[2]
Maximum rainfall2.59 in (66 mm) at Rockland, Maine[3]
FatalitiesNone reported
Power outages> 20,000[4]
Areas affectedNortheastern United States, New England, Atlantic Canada

The April 2021 nor'easter, also referred to as the 2021 Spring nor'easter, was a significant late-season nor'easter that impacted much of New England with heavy snowfall, gusty winds, thundersnow, and near-whiteout conditions from April 15–17, 2021. The system originated from a weak frontal system late on April 14 over North Carolina, which moved into the ocean the next day and began to strengthen. The low-pressure steadily deepened as it moved up the East Coast, and developed an eye-like feature just prior to peak intensity. It prompted a fairly large area of Winter Storm Warnings across interior sections of New England, with Winter Weather Advisories being issued closer to the coast. Over 20,000 customers lost power at the height of the storm on April 16 due to heavy wet snow, and near-whiteout conditions were reported in many areas.[4] Several injuries, some serious, occurred as well, mostly due to traffic incidents on poorly-treated roadways during the storm.[5][6][7] Damage estimates from the system are currently not calculated.

Meteorological history

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Map plotting the storm's track and intensity, according to the Saffir–Simpson scale
Map key
  Tropical depression (≤38 mph, ≤62 km/h)
  Tropical storm (39–73 mph, 63–118 km/h)
  Category 1 (74–95 mph, 119–153 km/h)
  Category 2 (96–110 mph, 154–177 km/h)
  Category 3 (111–129 mph, 178–208 km/h)
  Category 4 (130–156 mph, 209–251 km/h)
  Category 5 (≥157 mph, ≥252 km/h)
  Unknown
Storm type
triangle Extratropical cyclone, remnant low, tropical disturbance, or monsoon depression

The nor'easter formed as a weak frontal system at 18:00 UTC on April 14 over western North Carolina, along an already existing series of fronts stretching down the U.S. East Coast.[8] Several media outlets referred to the nor'easter as the "Spring nor'easter" due to its unusual occurrence in mid-spring.[9][10][11][12][13] It had transitioned into an extratropical cyclone by 12:00 UTC on April 15, as it moved offshore into the Atlantic Ocean and slowly began to strengthen.[14] The low-pressure then steadily strengthened as it moved northeastward up the coast, with its minimum central pressure dropping below 1,000 millibars (30 inHg) at 00:00 UTC on April 16.[15] The system then turned northwards towards the southeastern Massachusetts coastline, while beginning to strengthen faster.[16] Strong mesoscale banding developed in central and eastern Massachusetts, resulting in much higher snowfall totals than initially forecasted in those areas.[17][18]

The nor'easter then proceeded to make two consecutive landfalls, first in Dukes County, Massachusetts and again near Hyannis, Massachusetts between 12:00 and 15:00 UTC, as it reached its peak intensity of 988 millibars (29.2 inHg) over Cape Cod.[19] While maintaining peak intensity, the nor'easter made a third landfall near Kingston, Massachusetts at 21:00 UTC, before making a fourth and final landfall near Barnstable, Massachusetts at 00:00 UTC on April 17.[20][21] After this point, the nor'easter began to steadily weaken while moving northeast toward Nova Scotia, and later passing to the south of it.[22][23] The weakening nor'easter then slowly meandered east of Nova Scotia, moving to the northeast and making landfall along the southern coast of Newfoundland at 00:00 UTC on April 20, with a central pressure of 998 millibars (29.5 inHg).[24] After coming ashore, the nor'easter began to rapidly weaken, dissipating over eastern Newfoundland later that day.[25]

Preparations and impact

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Map of observed snowfall accumulations in the Northeastern United States from the storm

Early on April 14, Winter Storm Watches were issued in the higher elevations of interior New England,[26] and expanded to include more areas later that day.[27][28][29] The next day, many Winter Storm Watches were upgraded to Winter Storm Warnings, mainly in the higher elevations, while Winter Weather Advisories were issued in lower elevation areas closer to the coast.[30][31][32][33]

Northeastern United States

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Mid-Atlantic states

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Much of the Mid-Atlantic saw heavy, soaking rain from the nor'easter, in areas where temperatures weren't cold enough to support snow.[34] New York City picked up 0.83 inches (21 mm) of rain, and areas further to the north saw even more.[35] The rain resulted in a New York Mets game against the Philadelphia Phillies being postponed.[36] Up to 2.5 inches (64 mm) of rain was reported in the Mid-Atlantic, with the highest totals just outside of the New York metropolitan area.[37] The region also saw strong gusty winds from the storm, resulting in windswept rain in many areas. Some areas along the southern Long Island shore also reported minor coastal flooding due to the system.[6][38] The Adirondack Mountains of Upstate New York changed over to snow briefly on the back edge of the storm, and up to 6 inches (15 cm) accumulated on the highest peaks.[39]

New England

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Snowfall accumulation in Lexington, MA during the storm

In advance of the storm, Green Mountain Power in Vermont warned customers of possible power outages during the storm and prepared for restoring power if necessary. They also reminded customers to be prepared for power outages, possibly lasting up to a day. The Vermont Agency of Transportation warned of poor road conditions due to heavy wet snow, and closed VT 108 in Stowe prior to the storm to reduce work for snowplow operators.[40] In New Hampshire, dozens of school districts announced school closings or a switch to remote learning for April 16 in advance of the storm.[41]

In Rhode Island, a coating of snow was observed in Providence, with up to 4 inches (10 cm) falling in the northwestern part of the state. Snowflakes were even observed as far south as Narragansett Bay for a period of time.[6] In Massachusetts, the Berkshires and Worcester Hills in Massachusetts saw a widespread 6–12 inches (15–30 cm) of snow from the system, while the lower elevations of Greater Boston saw 1–3 inches (2.5–7.6 cm).[42] The Blue Hill Observatory in Milton picked up 3.6 inches (9.1 cm) of snow, making it the sixth-largest April snowstorm on record for the city.[6][43] The Boston area also observed occasional thundersnow on the morning of April 16, during the period of heaviest snow and highest instability.[6] High snowfall rates and snow-covered roads in central and eastern Massachusetts led MassDOT to deploy over 240 additional snowplows at 10 a.m. EDT on April 16.[18] A game between the Boston Red Sox and Chicago White Sox at Fenway Park was postponed due to the snow at the stadium.[44]

In New Hampshire, widespread snowfall amounts of 8–12 inches (20–30 cm) were observed, with some areas reporting even higher totals.[6] In Maine, the Portland International Jetport delayed a number of flights due to heavy snow and extremely gusty winds. At the airport, snowfall rates of over 1 in/hr (2.5 cm/hr) and wind gusts of over 50 mph (80 km/h) were observed.[6] Numerous crashes occurred on snow-covered roadways, with Maine State Police responding to three serious crashes. Crashes on roadways were the main source of injuries from the storm.[45] Snowfall accumulations weren't as high in Maine as neighboring states, but up to 9 inches (23 cm) of snow was observed in western areas of the state.[10][46]

Snowfall totals

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Highest observed snow totals from each affected state
State Town Amount
New Hampshire Lempster 14 inches (36 cm)
Massachusetts Princeton 12 inches (30 cm)
Vermont Winhall 11.1 inches (28 cm)
Maine Temple 8.3 inches (21 cm)
Connecticut Tolland 7.1 inches (18 cm)
New York Livingstonville 6 inches (15 cm)
Rhode Island North Foster 5.1 inches (13 cm)
Pennsylvania Ricketts Glen State Park 3 inches (7.6 cm)

See also

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References

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  1. ^ "HIGHEST WIND REPORTS National Weather Service Gray". NWS Gray. April 17, 2021. Retrieved April 21, 2021.
  2. ^ a b "SNOWFALL REPORTS National Weather Service Gray ME". NWS Gray. April 17, 2021. Retrieved April 21, 2021.
  3. ^ "24HR PRECIPITATION REPORTS National Weather Service Gray ME". NWS Gray. April 17, 2021. Retrieved April 21, 2021.
  4. ^ a b "PowerOutage.US". PowerOutage US. Retrieved April 17, 2021.
  5. ^ "Maine State Police respond to several car crashes within an hour due to spring storm". News Center Maine. Retrieved April 21, 2021.
  6. ^ a b c d e f g Cappucci, Matthew (April 16, 2021). "Wild spring storm pounds New England with thundersnow, strong winds". The Washington Post. Retrieved April 17, 2021.
  7. ^ Sonowoski, Alex (April 16, 2021). "Nor'easter walloping parts of Northeast with cold rain, April snow". Accuweather. Retrieved April 21, 2021.
  8. ^ "WPC surface analysis valid for 04/14/2021 at 18 UTC". Weather Prediction Center. April 14, 2021. Retrieved April 17, 2021.
  9. ^ "Spring nor'easter headed for northern New England". Associated Press. Retrieved April 20, 2021.
  10. ^ a b "Spring nor'easter headed for Maine this week". Bangor Daily News. Retrieved April 20, 2021.
  11. ^ "Spring nor'easter is underway". News Center Maine. Retrieved April 20, 2021.
  12. ^ "Snow way! A spring nor'easter is on tap for Maine Friday". WGME. Retrieved April 20, 2021.
  13. ^ "Spring nor'easter headed for Maine and NH later this week". WHDH Boston. Retrieved April 20, 2021.
  14. ^ "WPC surface analysis valid for 04/15/2021 at 12 UTC". Weather Prediction Center. April 15, 2021. Retrieved April 17, 2021.
  15. ^ "WPC surface analysis valid for 04/16/2021 at 00 UTC". Weather Prediction Center. April 16, 2021. Retrieved April 17, 2021.
  16. ^ "WPC surface analysis valid for 04/16/2021 at 12 UTC". Weather Prediction Center. April 16, 2021. Retrieved April 17, 2021.
  17. ^ "WPC surface analysis valid for 04/16/2021 at 09 UTC". Weather Prediction Center. April 16, 2021. Retrieved April 20, 2021.
  18. ^ a b "Look outside: Snow has reached Boston". The Boston Globe. Retrieved April 21, 2021.
  19. ^ "WPC surface analysis valid for 04/16/2021 at 15 UTC". Weather Prediction Center. April 16, 2021. Retrieved April 17, 2021.
  20. ^ "WPC surface analysis valid for 04/16/2021 at 21 UTC". Weather Prediction Center. April 16, 2021. Retrieved April 17, 2021.
  21. ^ "WPC surface analysis valid for 04/17/2021 at 00 UTC". Weather Prediction Center. April 17, 2021. Retrieved April 17, 2021.
  22. ^ "WPC surface analysis valid for 04/17/2021 at 21 UTC". Weather Prediction Center. April 17, 2021. Retrieved April 17, 2021.
  23. ^ "WPC surface analysis valid for 04/18/2021 at 09 UTC". Weather Prediction Center. April 18, 2021. Retrieved April 20, 2021.
  24. ^ "WPC surface analysis valid for 04/20/2021 at 00 UTC". Weather Prediction Center. April 20, 2021. Retrieved April 20, 2021.
  25. ^ "WPC surface analysis valid for 04/20/2021 at 18 UTC". Weather Prediction Center. April 20, 2021. Retrieved April 20, 2021.
  26. ^ NWS Burlington [@NWSBurlington] (April 14, 2021). "A Winter Storm Watch is in effect for portions of southern Vermont Thursday evening through Friday evening. Rain will transition to snow above 1000 feet Thursday night and be moderate to heavy at times through mid-day Friday. Storm total snowfall up to 6" is possible" (Tweet). Retrieved April 18, 2021 – via Twitter.
  27. ^ NWS Gray [@NWSGray] (April 14, 2021). "A Winter Storm Watch has been issued for portions of NH and W. ME. There remains some uncertainty in exact snowfall amounts but 6+" is possible for some, especially at elevations >800 feet. Power outages will be possible where significant accumulation occurs. #MEwx #NHwx" (Tweet). Retrieved April 18, 2021 – via Twitter.
  28. ^ NWS Albany [@NWSAlbany] (April 14, 2021). "A storm will bring widespread rain to the area with rain mixing with & changing to snow Thu night into early Fri especially across the higher terrain. A heavy wet snow of 6+ inches is possible for the Berkshires & southern Vermont mainly above 1500 feet. #nywx #ctwx #mawx #vtwx" (Tweet). Retrieved April 18, 2021 – via Twitter.
  29. ^ NWS Burlington [@NWSBurlington] (April 14, 2021). "Forecast remains on track for widespread rain to develop over northern New York and Vermont Thursday into Friday, but heavy snow is possible above 1000 feet across portions of central and southern Vermont. See graphic for details. #vtwx #nywx" (Tweet). Retrieved April 18, 2021 – via Twitter.
  30. ^ NWS Boston [@NWSBoston] (April 15, 2021). "[5 AM Thursday Update] Difficult forecast for this late season snow event coming up! Best chance of heavy, wet snow is in the Berkshires and Worcester Hills, with rain elsewhere. This forecast will be adjusted before snow starts tonight so check back for the latest!" (Tweet). Retrieved April 18, 2021 – via Twitter.
  31. ^ NWS Albany [@NWSAlbany] (April 15, 2021). "A soaking rain is expected today. As colder air filters in tonight, rain will change over to a rain snow mix or all snow. Occasional rain and wet snow will continue on Friday before ending Friday night. #vtwx #mawx #ctwx #nywx" (Tweet). Retrieved April 18, 2021 – via Twitter.
  32. ^ NWS Gray [@NWSGray] (April 15, 2021). "A Winter Storm Warning is in effect for most of New Hampshire and portions of western Maine. Heavy wet snow will overspread the region tonight and continue throughout the day tomorrow. Scattered power outages are possible. For more information, go to https://weather.gov/gyx/winter" (Tweet). Retrieved April 18, 2021 – via Twitter.
  33. ^ "Winter Weather Returns to New England". WeatherNation. April 16, 2021. Retrieved April 21, 2021.
  34. ^ "Coastal low brings soaking rain to the Northeast, and snow for some". Spectrum News. Retrieved April 18, 2021.
  35. ^ "In April 2007, a nor'easter brought major rain to NYC". Spectrum News. Retrieved April 18, 2021.
  36. ^ Mets-Phillies postponed today, MLB.com, April 15, 2021
  37. ^ "Public Information Statement National Weather Service New York NY". NWS New York. April 16, 2021. Retrieved April 21, 2021.
  38. ^ "Nor'easter to wallop Northeast with cold rain and April snow". Microsoft News. Retrieved April 18, 2021.
  39. ^ "04/15/2021: Transition to snow starting to take place…. in the high terrain…". News 10 Albany. 15 April 2021. Retrieved April 20, 2021.
  40. ^ "Forecasts call for heavy, wet snow, possible outages across higher elevations". Vermontbiz. April 15, 2021. Retrieved April 23, 2021.
  41. ^ "Dozens of closings, delays, switches to remote learning reported in New Hampshire". WMUR. April 16, 2021. Retrieved April 23, 2021.
  42. ^ "Nor'easter starts slogging, soaking journey through New England". The Boston Globe. April 16, 2021. Retrieved April 23, 2021.
  43. ^ BlueHill Observatory [@bhobservatory] (April 16, 2021). "The rain is making the snow melt now. We had a grand total of 3.6" which beats the prior April 16 record of 2.0" set in 1904 and 1962. That makes today the 6th snowiest late season snow storm since 1885" (Tweet). Retrieved May 14, 2021 – via Twitter.
  44. ^ Nor'easter postpones Friday night's Red Sox game, WCVB, April 16, 2021
  45. ^ "Maine State Police respond to several car crashes within an hour due to spring storm". News Center Maine. April 16, 2021. Retrieved April 23, 2021.
  46. ^ "It's True: Maine is Getting a Spring Nor'easter". April 15, 2021. Retrieved April 23, 2021.
  47. ^ NWS Eastern Region [@NWSEastern] (April 16, 2021). "Spring snowfall update...Snowfall totals received as of 6 pm Friday April 16th. Highest totals so far by state:" (Tweet). Retrieved April 20, 2021 – via Twitter.
  48. ^ "Spotter Reports National Weather Service Boston/Norton MA". NWS Boston. April 17, 2021. Retrieved April 21, 2021.
  49. ^ "Spotter Reports National Weather Service State College PA". NWS State College. April 16, 2021. Retrieved April 21, 2021.
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