Coastal Flood and Heavy Snow in Massachusetts, December 16 to 17, 2020

Name: Coastal Flood and Heavy Snow in Massachusetts, December 16 to 17, 2020
Start: 2020-12-16T21:00
End: 2020-12-17T13:00
Location: Massachusetts

December 16 to 17, 2020 · NWS BOX · 24 events in 22 counties and zones

A storm system produced heavy snow, strong to damaging winds, and minor coastal flooding in southern New England. This was a tough storm to forecast.

Where it happened

Every event with a place to put it; 24 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 24

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS BOX wrote it up.

A storm system produced heavy snow, strong to damaging winds, and minor coastal flooding in southern New England. This was a tough storm to forecast. Although it was not deep low pressure and although it passed just south of the 40N/70W benchmark, its precipitation shield was expansive because of a broad 700 mb low over southeast New England, abundant moisture, and a very cold air mass in place. By far, the heaviest snow fell to the north (Laconia, NH) and west (Binghamton, NY), where more than 3 feet fell. But amounts ranged from 10 to 20 inches across much of southern New England. There was some minor coastal flooding at the time of high tide and also a flash freeze in eastern Massachusetts as the storm pulled away to the northeast.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Boston/Norton, MA wrote its last area forecast discussion before the first event at Dec 16, 7:42 PM EST, 1 hour 18 minutes earlier.

Area forecast discussion, Dec 16, 7:42 PM EST, 1 hour 18 minutes before

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In the hours before

Special weather statement, Dec 16, 8:54 PM EST, 6 minutes before

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The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

22 heavy snow, 2 coastal flood. Local standard time, as filed.

Heavy Snow, Western Franklin

When: December 16, 9:00 PM EST to December 17, 12:00 PM EST
Where: Western Franklin forecast zone
Reported by: COOP Observer
Coordinates: 42.583, -72.592 (the zone’s center; the record gives no point)

Heavy snow ranged from 10 to 20 inches in western Franklin County, in the east slopes of the Berkshires. Some specific amounts included 20.0 in East Hawley (Co-Op observer), 17.7 inches in Rowe (Co-Op observer), 17.5 inches in Colrain (CoCoRaHS), 17.2 inches in Buckland (CoCoRaHS), 16.3 inches in Conway (CoCoRaHS), 12.5 inches in Leyden (public), and 10.0 inches in Heath (amateur radio). Winds generally were gusting to 20 to 30 mph.

Heavy Snow, Eastern Franklin

When: December 16, 9:00 PM EST to December 17, 12:00 PM EST
Where: Eastern Franklin forecast zone
Reported by: CoCoRaHS
Coordinates: 42.583, -72.592 (the zone’s center; the record gives no point)

Heavy snow ranged from 7 to 17 inches across eastern Franklin County. Some specific amounts included 17.0 inches in Montague (CoCoRaHS), 16.2 inches in Greenfield (public), 12.0 inches in New Salem (trained spotter), 11.6 inches in Sunderland (CoCoRaHS), 11.0 inches in Bernardston (CoCoRaHS), 8.0 inches in Leverett (Co-Op observer), and 7.0 inches in Shutesbury (amateur radio). Winds generally were gusting to 20 to 30 mph.

Heavy Snow, Western Hampden

When: December 16, 9:00 PM EST to December 17, 12:00 PM EST
Where: Western Hampden forecast zone
Reported by: CoCoRaHS
Coordinates: 42.135, -72.632 (the zone’s center; the record gives no point)

While no reports were received from the hill towns in western Hampden County, per se, we are estimating that heavy snow on the order of 10 to 20 inches fell, based on reports from surrounding areas. Winds generally were gusting to 20 to 30 mph.

Heavy Snow, Eastern Hampden

When: December 16, 9:00 PM EST to December 17, 12:00 PM EST
Where: Eastern Hampden forecast zone
Reported by: Trained Spotter
Coordinates: 42.135, -72.632 (the zone’s center; the record gives no point)

Heavy snow ranged from about 8 to 13 inches in eastern Hampden County. Some specific amounts included 13.0 inches in both Longmeadow (trained spotter) and Agawam (public), 12.2 inches in Westfield (KBAF CWO), 11.5 inches in Springfield (trained spotter), 10.8 inches in East Longmeadow (CoCoRaHS), 10.2 inches in West Springfield (CoCoRaHS), and 8.0 inches in Monson (amateur radio). Winds generally were gusting to 30 to 35 mph.

Heavy Snow, Western Hampshire

When: December 16, 9:00 PM EST to December 17, 12:00 PM EST
Where: Western Hampshire forecast zone
Reported by: CoCoRaHS
Coordinates: 42.340, -72.664 (the zone’s center; the record gives no point)

Heavy snow ranged from 9 to 20.5 inches across western Hampshire County, with the highest amounts in the immediate east slopes of the Berkshires. Some specific totals included 20.5 inches in Westhampton (CoCoRaHS), 20.0 inches on the west side of Plainfield (CoCoRaHS), 17.0 inches in Goshen (broadcast media), 12.0 inches in Huntington (trained spotter), 12.0 inches on the east side of Plainfield (CoCoRaHS), and 9.0 inches in Williamsburg (CoCoRaHS). Winds generally were gusting to 20 to 30 mph.

Heavy Snow, Eastern Hampshire

When: December 16, 9:00 PM EST to December 17, 12:00 PM EST
Where: Eastern Hampshire forecast zone
Reported by: COOP Observer
Coordinates: 42.340, -72.664 (the zone’s center; the record gives no point)

Heavy snow ranged from 7.5 to 12.7 inches across eastern Hampshire County. Some specific totals included 12.7 inches in Amherst (Co-Op observer), 10.0 inches in Northampton (trained spotter), 10.0 inches in Easthampton (amateur radio), 8.0 inches in Hadley (amateur radio), and 7.5 inches in Belchertown (amateur radio). Winds generally were gusting to 25-35 mph.

Heavy Snow, Northwest Middlesex County

When: December 16, 9:00 PM EST to December 17, 12:00 PM EST
Where: Northwest Middlesex County forecast zone
Reported by: Public
Coordinates: 42.486, -71.392 (the zone’s center; the record gives no point)

Heavy snow ranged from 10.5 to 14.5 inches across northwest Middlesex County. Some specific totals included 14.5 inches in Ashby (general public), 13.0 inches in West Townsend (trained spotter), 10.9 inches in Townsend (trained spotter), and 10.5 inches in Pepperell (trained spotter). Winds generally were gusting to 25 to 35 mph.

Heavy Snow, Northern Worcester

When: December 16, 9:00 PM EST to December 17, 12:00 PM EST
Where: Northern Worcester forecast zone
Reported by: Trained Spotter
Coordinates: 42.351, -71.908 (the zone’s center; the record gives no point)

Heavy snow in northern Worcester County generally ranged from 9 to 15 inches. Some specific amounts included 15.1 inches in Lunenburg (trained spotter), 14.0 inches in Winchendon (amateur radio), 12.9 inches in Leicester (CoCoRaHS), 12.8 inches in Fitchburg (CoOp observer), 11.5 inches in Hubbardston (public), 11.0 in Ashburnham (CoOp observer), 10.2 inches in Boylston (trained spotter), 10.0 inches in Berlin (CoCoRaHS), 10.0 inches in Harvard (CoCoRaHS), and 9.8 inches in Barre (trained spotter). Winds generally were gusting to 25 to 35 mph.

Heavy Snow, Barnstable

When: December 16, 10:00 PM EST to December 17, 1:00 PM EST
Where: Barnstable forecast zone
Reported by: COOP Observer
Coordinates: 41.684, -70.274 (the zone’s center; the record gives no point)

Snowfall ranged from 2 to 4 inches on the outer Cape to up to 6 to 7.7 inches on the upper Cape. More specifically, some snow totals included 7.7 inches in East Sandwich (CoOp Observer), 6.5 inches in West Falmouth (amateur radio), 5.6 inches in Yarmouth (CoCORaHS), 5.5 inches in Hyannis (WOCN radio), 5.0 inches in Harwich (amateur radio), 4.0 inches in Orleans (CoCoRaHS), and 2.7 inches in Eastham (CoCoRaHS). Peak wind gusts during the afternoon of the 17th included 49 mph at Dennis (CWOP), 46 mph at Hyannis Airport (KHYA ASOS), and 36 mph at the Chatham Airport (KCQX ASOS).

Heavy Snow, Northern Bristol

When: December 16, 10:00 PM EST to December 17, 1:00 PM EST
Where: Northern Bristol forecast zone
Reported by: Official NWS Observations
Coordinates: 41.757, -71.088 (the zone’s center; the record gives no point)

Heavy snow generally ranged 7 to 10 inches in northern Bristol County. Winds generally were gusting to 30 to 40 mph. Some specific snowfall totals included 10.3 inches at the National Weather Service Forecast Office in Norton, 10.0 inches in Mansfield, 9.4 inches in Dighton, and 7.4 inches in Rehoboth.

Heavy Snow, Western Plymouth

When: December 16, 10:00 PM EST to December 17, 1:00 PM EST
Where: Western Plymouth forecast zone
Reported by: Trained Spotter
Coordinates: 41.987, -70.737 (the zone’s center; the record gives no point)

Heavy snow generally ranged from 8 to 14 inches across western Plymouth County, with the highest amounts closest to eastern Norfolk County. Some specific snowfall amounts included 14.2 inches in Whitman (trained spotter), 13.6 inches in Rockland (trained spotter), 11.2 inches in Pembroke (CoCoRaHS), 9.0 inches in East Bridgewater (amateur radio), 8.5 inches in Hanover (amateur radio), 8.0 inches in Lakeville (amateur radio), and 8.0 inches in Middleboro (Twitter report). Winds generally were gusting to 35 to 40 mph.

Heavy Snow, Southern Bristol

When: December 16, 10:00 PM EST to December 17, 1:00 PM EST
Where: Southern Bristol forecast zone
Reported by: CoCoRaHS
Coordinates: 41.757, -71.088 (the zone’s center; the record gives no point)

Heavy snow averaged 5 to 6 inches across southern Bristol County, but ranged from a low of 3.7 inches in Dartmouth (CoCoRaHS) to a high of 7.6 inches in Somerset (CoCoRaHS). Other reports included 6.2 inches in Fairhaven (amateur radio), 5.8 inches in Acushnet (amateur radio), and 5.0 inches in New Bedford (amateur radio). Winds generally were gusting to 35 to 40 mph, with a peak wind gust of 43 mph recorded by a CWOP station on West Island in Fairhaven at 201 PM EST.

Heavy Snow, Eastern Plymouth

When: December 16, 10:00 PM EST to December 17, 1:00 PM EST
Where: Eastern Plymouth forecast zone
Reported by: CoCoRaHS
Coordinates: 42.079, -70.960 (the zone’s center; the record gives no point)

Heavy snow generally ranged from 6.5 to 14 inches across eastern Plymouth County, Some specific snowfall amounts included 14.1 inches in Kingston (CoCoRaHS), 11.4 inches in Hingham (CoCoRaHS), 9.5 inches in Marshfield (CoCoRaHS), 8.7 inches in Duxbury (NWS Employee), and 6.6 inches in Plymouth (CoCoRaHS). Winds generally were gusting to 40 to 50 mph. In Marshfield at 155 PM EST, the ASOS at the Marshfield Airport (KGHG) recorded a gust to 43 mph. In Plymouth at 152 PM EST, the ASOS at the Airport (KPYM) recorded a gust to 41 mph. In nearby Wareham at 253 PM EST, a CWOP station had a gust to 47 mph.

Heavy Snow, Southern Plymouth

When: December 16, 10:00 PM EST to December 17, 1:00 PM EST
Where: Southern Plymouth forecast zone
Reported by: Trained Spotter
Coordinates: 41.987, -70.737 (the zone’s center; the record gives no point)

Snowfall averaged 6 to 7 inches in southern Plymouth County. In Wareham, a trained spotter reported 6.4 inches. In nearby Plymouth, a CoCoRaHS observer reported 6.6 inches. Winds generally were gusting to 40 to 50 mph. In Wareham at 253 PM EST, a CWOP station had a gust to 47 mph. At the Plymouth Airport (KPYM) at 152 PM, the ASOS recorded a gust to 41 mph.

Heavy Snow, Western Essex

When: December 16, 10:00 PM EST to December 17, 1:00 PM EST
Where: Western Essex forecast zone
Reported by: COOP Observer
Coordinates: 42.639, -70.868 (the zone’s center; the record gives no point)

Heavy snowfall generally ranged from 8 to 15 inches in western Essex County. Specific amounts included 14.9 inches in Middleton (CoOp observer), 12.5 inches in Topsfield (public), 12.5 inches in Haverhill (public), 12.5 inches in Methuen (trained spotter), 11.5 inches in North Andover (CoCoRaHS), and 10.5 inches in Boxford (CoCoRaHS), and 8.5 inches in Lawrence (CoOp observer). Winds generally were gusting to 30-40 mph.

Heavy Snow, Eastern Essex

When: December 16, 10:00 PM EST to December 17, 1:00 PM EST
Where: Eastern Essex forecast zone
Reported by: Trained Spotter
Coordinates: 42.639, -70.868 (the zone’s center; the record gives no point)

Heavy snow ranged mainly from 10 to 15 inches across eastern Essex County. Some specific amounts included 15.0 inches in Salem (trained spotter), 15.0 inches in Ipswich (trained spotter), 14.0 inches in Beverly (amateur radio), 13.0 inches in Gloucester (trained spotter), 12.3 inches in Danvers (amateur radio), 12.0 inches in Peabody (amateur radio), 11.3 inches in Newburyport (CoCoRaHS), and 10.5 inches in Rockport (CoCoRaHS). Winds gusted to 51 mph at a CWOP station in Rockport at 105 PM EST but generally were gusting to 30 to 40 mph during the afternoon.

Heavy Snow, Western Middlesex

When: December 16, 10:00 PM EST to December 17, 1:00 PM EST
Where: Western Middlesex forecast zone
Reported by: Public
Coordinates: 42.486, -71.392 (the zone’s center; the record gives no point)

Heavy snow ranged from 9.0 to 15.2 inches across western Middlesex County. Some specific amounts included 15.2 inches in Lowell (public), 15.0 inches in Hudson (public via Twitter), 14.7 inches in Sudbury (amateur radio), 14.5 inches in Framingham (CoCoRaHS), 14.0 inches in Marlboro (amateur radio), 14.0 inches in Sudbury (CoCoRaHS), 14.0 inches in Bedford (trained spotter), 13.7 inches in Tewksbury (trained spotter), 13.5 inches in Holliston (CoCoRaHS), 13.2 inches in Sherborn (trained spotter), 10.0 inches in Lincoln (CoCoRaHS), and 9.0 inches in Carlisle (amateur radio). Winds generally were gusting to 25 to 35 mph.

Heavy Snow, Southeast Middlesex

When: December 16, 10:00 PM EST to December 17, 1:00 PM EST
Where: Southeast Middlesex forecast zone
Reported by: Trained Spotter
Coordinates: 42.486, -71.392 (the zone’s center; the record gives no point)

Heavy snow generally ranged from 12 to 16 inches across southeast Middlesex County. Some specific amounts included 16.0 inches in Waltham (trained spotter), 15.0 inches in West Newton (public), 14.6 inches in Winchester (CoCoRaHS), 14.5 inches in Melrose (CoCoRaHS), 14.5 inches in Wakefield (trained spotter), 13.5 inches in Somerville (CoCoRaHS), 13.3 inches in Lexington (public), and 12.0 inches in Cambridge (CoCoRaHS). Winds generally were gusting to 30 to 35 mph.

Heavy Snow, Western Norfolk

When: December 16, 10:00 PM EST to December 17, 1:00 PM EST
Where: Western Norfolk forecast zone
Reported by: Public
Coordinates: 42.171, -71.184 (the zone’s center; the record gives no point)

Heavy snow generally ranged from 9 to 15.4 inches in western Norfolk County. Some specific amounts included 15.4 inches in Sharon (public), 13.2 inches in Randolph (trained spotter), 13.0 inches in Walpole (amateur radio), 13.0 inches in Wrentham (amateur radio), 12.0 inches in Foxboro (NWS employee), 11.8 inches in Norwood (CoCoRaHS), 11.5 inches in Dover (amateur radio), 11.5 inches in Millis (CoCoRaHS), 10.0 inches in Franklin (amateur radio), and 9.6 inches in Medway (public). Winds generally were gusting to 20-30 mph.

Heavy Snow, Eastern Norfolk

When: December 16, 10:00 PM EST to December 17, 1:00 PM EST
Where: Eastern Norfolk forecast zone
Reported by: COOP Observer
Coordinates: 42.171, -71.184 (the zone’s center; the record gives no point)

Heavy snow generally ranged from 12.0 to 16.5 inches in eastern Norfolk County. Some specific amounts included 16.5 inches from the Cooperative Observer atop the Blue Hill in Milton, 13.4 inches in Quincy (public), 13.0 inches in Weymouth (trained spotter), 13.0 inches in Braintree (trained spotter), and 12.0 inches in North Weymouth (amateur radio). Winds generally were gusting to 30 to 35 mph. At 251 PM EST on the 17th, the ASOS at the Blue Hill Observatory in Milton (KMQE) recorded a gust to 36 mph.

Heavy Snow, Suffolk

When: December 16, 10:00 PM EST to December 17, 1:00 PM EST
Where: Suffolk forecast zone
Reported by: COOP Observer
Coordinates: 42.264, -71.125 (the zone’s center; the record gives no point)

Heavy snow fell in the Boston area, generally ranging from 12 to 18 inches. Some specific amounts included 17.6 inches in the Jamaica Plain section of Boston (CoOp observer), 13.5 inches in Dorchester (trained spotter), 13.3 inches in Chelsea (trained spotter), and 12.7 inches at Logan International Airport. Winds generally were gusting to 30 to 35 mph. At 1254 PM EST on the 17th, the ASOS at Boston's Logan International Airport (KBOS) recorded a gust to 33 mph.

Heavy Snow, Southern Worcester

When: December 16, 10:00 PM EST to December 17, 1:00 PM EST
Where: Southern Worcester forecast zone
Reported by: Trained Spotter
Coordinates: 42.351, -71.908 (the zone’s center; the record gives no point)

Heavy snow in southern Worcester County generally ranged from 10 to 16 inches. Some specific amounts included 16.1 inches in Grafton (trained spotter), 13.3 inches in Milford (trained spotter), 12.5 inches in Westborough (NWS employee), 12.1 inches at the Worcester Airport, 11.7 inches in Northborough (CoCoRaHS), 11.6 inches in Southbridge (CoOp observer), and 10.0 inches in Shrewsbury (public). Winds generally were gusting to 25 to 35 mph. At 154 PM EST on the 17th, the ASOS at the Worcester Airport (KORH) recorded a gust to 36 mph.

Coastal Flood, Eastern Plymouth

When: December 17, 12:05 PM EST to 12:57 PM EST
Where: Eastern Plymouth forecast zone
Reported by: Amateur Radio
Coordinates: 42.079, -70.960 (the zone’s center; the record gives no point)

Minor coastal flooding occurred around the time of high tide. In Hull at 1205 PM EST, there was minor flooding on Nantasket Avenue at the wastewater treatment plant. In Scituate at 1226 PM EST, the media posted a video of minor coastal flooding. In Plymouth at 1244 PM EST, Warren Avenue was closed from coastal flooding. In Marshfield at 1257 PM EST, minor coastal flooding made Plymouth Avenue impassable and Ocean Street closed near the Esplanade.

Coastal Flood, Suffolk

When: December 17, 12:05 PM EST to 12:38 PM EST
Where: Suffolk forecast zone
Reported by: Amateur Radio
Coordinates: 42.264, -71.125 (the zone’s center; the record gives no point)

Minor coastal flooding occurred around the time of high tide. In Boston at 1205 PM EST, Two lanes both northbound and southbound of Morrissey Blvd. were closed between UMass and Freeport Street. In Revere at 1235 PM EST, there was minor flooding on Mills Avenue by River Avenue. In Winthrop at 1238 PM EST, Revere Street/Winthrop Shore Drive was closed from Crest Avenue to the Revere town line due to minor coastal flooding.

What these are

Heavy Snow: Snowfall reaching the local warning threshold without the other hazards of a winter storm.
Coastal Flood: Flooding of coastal land by the sea, from storm surge, onshore wind or high tides.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Massachusetts in 2020 Every state in 2020 This day in weather history Warnings in Massachusetts, December 2020

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-10-01. Each event’s entry at NCEI: 928230, 928232, 928434, 928435, 928436, 928437, 928438, 928455, 928213, 928215, 928216, 928217, 928221, 928223, 928226, 928227, 928439, 928440, 928441, 928442, 928443, 928456, 928224, 928225.