New Hampshire, 2020

Winter Storm in New Hampshire, March 23 to 24, 2020

March 23 to 24, 2020 · NWS GYX · 13 events in 13 counties and zones

Low pressure west of the Appalachian Mountains on the 23rd underwent secondary development along a baroclinic zone lingering off the Mid Atlantic coast. That secondary area of low pressure steadily deepened as it moved northeastward into the Gulf of Maine by the 24th.

Where it happened

Every event with a place to put it; 13 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
13

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 GYX wrote it up.

Low pressure west of the Appalachian Mountains on the 23rd underwent secondary development along a baroclinic zone lingering off the Mid Atlantic coast. That secondary area of low pressure steadily deepened as it moved northeastward into the Gulf of Maine by the 24th. Mid level low centers developed in a location that ensured that warm air struggled to get very far north and prevented most of the mixed precipitation potential. That and a cool and dry antecedent air mass meant that the predominate precipitation type was snow across most of New Hampshire.

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 Gray, ME wrote its last area forecast discussion before the first event at Mar 23, 10:57 AM EST, 3 hours 3 minutes earlier.

Area forecast discussion, Mar 23, 10:57 AM EST, 3 hours 3 minutes before
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Hazardous weather outlook, Mar 23, 1:44 PM EST, 16 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

13 winter storm. Local standard time, as filed.

Winter Storm, Cheshire

When
March 23, 2:00 PM EST to 11:00 PM EST
Where
Cheshire forecast zone
Reported by
Trained Spotter
Coordinates
42.919, -72.251 (the zone’s center; the record gives no point)

Snow moved into the Connecticut River Valley during the afternoon on the 23rd and quickly became moderate to heavy. Forcing was driven primarily by warm air advection and banding near the low center never made it far enough northwest to affect the area, and so came to an end in less than 12 hours. Snowfall rates approached one inch per hour at times in the evening, before tapering off quickly around midnight. Total snowfall ranged from 5 to 8 inches.

Winter Storm, Sullivan

When
March 23, 3:00 PM EST to 11:00 PM EST
Where
Sullivan forecast zone
Reported by
Trained Spotter
Coordinates
43.361, -72.222 (the zone’s center; the record gives no point)

Snow moved into the Connecticut River Valley during the afternoon on the 23rd and quickly became moderate to heavy. Forcing was driven primarily by warm air advection and banding near the low center never made it far enough northwest to affect the area, and so came to an end in less than 12 hours. Snowfall rates approached one inch per hour at times in the evening, before tapering off quickly around midnight. Total snowfall ranged from 5 to 7 inches.

Winter Storm, Merrimack

When
March 23, 3:00 PM EST to March 24, 1:00 AM EST
Where
Merrimack forecast zone
Reported by
Trained Spotter
Coordinates
43.298, -71.680 (the zone’s center; the record gives no point)

Snow moved into the central New Hampshire during the afternoon on the 23rd and quickly became moderate to heavy. Forcing was driven primarily by warm air advection and banding near the low center never made it far enough northwest to affect the area, and so came to an end in less than 12 hours. Snowfall rates approached one inch per hour at times in the evening, before tapering off quickly around midnight. Total snowfall ranged from 5 to 8 inches.

Winter Storm, Western and Central Hillsborough

When
March 23, 3:00 PM EST to March 24, 1:00 AM EST
Where
Western and Central Hillsborough forecast zone
Reported by
Trained Spotter
Coordinates
42.915, -71.716 (the zone’s center; the record gives no point)

Snow moved into the Monadnock region during the afternoon on the 23rd and quickly became moderate to heavy. While forcing was driven primarily by warm air advection, a band of heavy snow developed northwest of the low center and did manage to lift into the area. This extended the duration of snow in addition to producing snowfall rates of one inch per hour at times in the evening. Snow tapered off quickly after midnight. Total snowfall ranged from 6 to 8 inches, with locally higher amounts around 10 inches in the Monadnocks.

Winter Storm, Eastern Hillsborough

When
March 23, 3:00 PM EST to March 24, 2:00 AM EST
Where
Eastern Hillsborough forecast zone
Reported by
Trained Spotter
Coordinates
42.915, -71.716 (the zone’s center; the record gives no point)

Snow moved into Nashua and Manchester during the afternoon on the 23rd and quickly became moderate to heavy. While forcing was driven primarily by warm air advection, a band of heavy snow developed northwest of the low center and did manage to lift into the area. This extended the duration of snow in addition to producing snowfall rates of one inch per hour at times in the evening. Snow tapered off quickly after midnight. Total snowfall ranged from 6 to 7 inches.

Winter Storm, Interior Rockingham

When
March 23, 3:00 PM EST to March 24, 2:00 AM EST
Where
Interior Rockingham forecast zone
Reported by
Trained Spotter
Coordinates
42.985, -71.089 (the zone’s center; the record gives no point)

Snow moved into southeastern New Hampshire during the afternoon on the 23rd and quickly became moderate to heavy. While forcing was driven primarily by warm air advection, a band of heavy snow developed northwest of the low center and did manage to lift into the area. This extended the duration of snow in addition to producing snowfall rates of one inch per hour at times in the evening. Snow tapered off quickly after midnight. Total snowfall ranged from 5 to 8 inches.

Winter Storm, Southern Coos

When
March 23, 4:00 PM EST to March 24, 12:00 AM EST
Where
Southern Coos forecast zone
Reported by
Trained Spotter
Coordinates
44.690, -71.305 (the zone’s center; the record gives no point)

Snow moved into the White Mountains during the afternoon on the 23rd and quickly became moderate to heavy. Forcing was driven primarily by warm air advection and banding near the low center never made it far enough northwest to affect the area, and so came to an end in less than 12 hours. Snow tapered off quickly around midnight. Total snowfall ranged from 8 to 11 inches.

Winter Storm, Northern Grafton

When
March 23, 4:00 PM EST to 11:00 PM EST
Where
Northern Grafton forecast zone
Reported by
Trained Spotter
Coordinates
43.941, -71.820 (the zone’s center; the record gives no point)

Snow moved into the White Mountains during the afternoon on the 23rd and quickly became moderate to heavy. Forcing was driven primarily by warm air advection and banding near the low center never made it far enough northwest to affect the area, and so came to an end in less than 12 hours. Snow tapered off quickly around midnight. Total snowfall ranged from 6 to 9 inches.

Winter Storm, Northern Carroll

When
March 23, 4:00 PM EST to March 24, 12:00 AM EST
Where
Northern Carroll forecast zone
Reported by
Trained Spotter
Coordinates
43.874, -71.203 (the zone’s center; the record gives no point)

Snow moved into the White Mountains during the afternoon on the 23rd and quickly became moderate to heavy. Forcing was driven primarily by warm air advection and banding near the low center never made it far enough northwest to affect the area, and so came to an end in less than 12 hours. Snow tapered off quickly around midnight. Total snowfall ranged from 6 to 8 inches.

Winter Storm, Southern Grafton

When
March 23, 4:00 PM EST to 11:00 PM EST
Where
Southern Grafton forecast zone
Reported by
Trained Spotter
Coordinates
43.941, -71.820 (the zone’s center; the record gives no point)

Snow moved into the White Mountains during the afternoon on the 23rd and quickly became moderate to heavy. Forcing was driven primarily by warm air advection and banding near the low center never made it far enough northwest to affect the area, and so came to an end in less than 12 hours. Snowfall rates approached one inch per hour at times in the evening, before tapering off quickly around midnight. Total snowfall ranged from 6 to 8 inches.

Winter Storm, Southern Carroll

When
March 23, 4:00 PM EST to March 24, 1:00 AM EST
Where
Southern Carroll forecast zone
Reported by
Trained Spotter
Coordinates
43.874, -71.203 (the zone’s center; the record gives no point)

Snow moved into the White Mountains during the afternoon on the 23rd and quickly became moderate to heavy. Forcing was driven primarily by warm air advection and banding near the low center never made it far enough northwest to affect the area, and so came to an end in less than 12 hours. Snowfall rates approached one inch per hour at times in the evening, before tapering off quickly around midnight. Total snowfall ranged from 6 to 8 inches.

Winter Storm, Belknap

When
March 23, 4:00 PM EST to March 24, 1:00 AM EST
Where
Belknap forecast zone
Reported by
Trained Spotter
Coordinates
43.519, -71.423 (the zone’s center; the record gives no point)

Snow moved into the Lakes Region during the afternoon on the 23rd and quickly became moderate to heavy. Forcing was driven primarily by warm air advection and banding near the low center never made it far enough northwest to affect the area, and so came to an end in less than 12 hours. Snowfall rates approached one inch per hour at times in the evening, before tapering off quickly around midnight. Total snowfall ranged from 5 to 7 inches.

Winter Storm, Strafford

When
March 23, 4:00 PM EST to March 24, 2:00 AM EST
Where
Strafford forecast zone
Reported by
Trained Spotter
Coordinates
43.297, -71.029 (the zone’s center; the record gives no point)

Snow moved into southeastern New Hampshire during the afternoon on the 23rd and quickly became moderate to heavy. While forcing was driven primarily by warm air advection, a band of heavy snow developed northwest of the low center and did manage to lift into the area. This extended the duration of snow in addition to producing snowfall rates of one inch per hour at times in the evening. Snow tapered off quickly after midnight. Total snowfall ranged from 6 to 7 inches.

What these are

Winter Storm
A storm that brought snow, sleet or freezing rain at warning levels, usually over several hours or days.

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

The same day elsewhere

More

Every storm in New Hampshire in 2020Every state in 2020This day in weather historyWarnings in New Hampshire, March 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: 875635, 875634, 875636, 875638, 875639, 875640, 875629, 875630, 875631, 875632, 875633, 875637, 875641.