Flooding and Heavy Snow in New Hampshire, April 15 to 18, 2007

Name: Flooding and Heavy Snow in New Hampshire, April 15 to 18, 2007
Start: 2007-04-15T07:00
End: 2007-04-18T10:00
Location: New Hampshire

April 15 to 18, 2007 · NWS BOX · 4 events in 3 counties and zones

An unusually strong and slow moving coastal storm for mid April tracked to western Long Island Sound, before weakening slowly and drifting offshore. |Snowfall totals as high as 4 to 8 inches were observed in the higher elevations of Cheshire County.

Where it happened

Every event with a place to put it; 2 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
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Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
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The toll

Deaths: 0
Injuries: 0
Property damage: $1.6 million
Crop damage: None recorded
Events: 4

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.

An unusually strong and slow moving coastal storm for mid April tracked to western Long Island Sound, before weakening slowly and drifting offshore. This storm brought a variety of impacts to southwest New Hampshire, including heavy snow to the higher elevations and widespread river and stream flooding.|Snowfall totals as high as 4 to 8 inches were observed in the higher elevations of Cheshire County. There were numerous reports of downed trees and power lines in these areas from the weight of the heavy, wet snow. |Rainfall totals of 3 to 5 inches, combined with wet antecedent conditions, resulted in widespread river and stream flooding, as well as significant flooding of urban areas. The worst flooding affected the Merrimack Valley, where moderate to major flooding occurred on the Merrimack, Nashua, Piscataquog, and Souhegan Rivers. For many locations, this may have been the worst flooding since the May, 2006 or April, 1987 floods but along the Piscataquog and Souhegan Rivers the preliminary crests recorded may have been the highest since the floods of September, 1938.|Many small streams throughout the region also rose out of their banks and flooded nearby areas, including roadways. Significant flooding|occurred along small streams in Hillsborough County, where a portion of Route 122 was closed in Hollis and a mudslide closed Route 101 in Wilton.

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 Apr 15, 7:00 AM EST, 0 minutes earlier.

Area forecast discussion, Apr 15, 7:00 AM EST, 0 minutes before

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Hazardous weather outlook, Apr 15, 2:27 AM EST, 4 hours 33 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

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

Heavy Snow, Cheshire

When: April 15, 7:00 AM EST to 5:00 PM EST
Where: Cheshire forecast zone
Property damage: $20,000
Reported by: Trained Spotter
Coordinates: 42.919, -72.251 (the zone’s center; the record gives no point)

Heavy Snow, Western and Central Hillsborough

When: April 15, 7:00 AM EST to 5:00 PM EST
Where: Western and Central Hillsborough forecast zone
Property damage: $15,000
Reported by: Trained Spotter
Coordinates: 42.915, -71.716 (the zone’s center; the record gives no point)

Flood, Hillsborough

When: April 16, 5:00 AM EST to April 18, 10:00 AM EST
Where: Hillsborough County, Peterborough to Manchester
Cause: Heavy Rain
Property damage: $1.5 million
Reported by: Amateur Radio
Coordinates: 42.870, -71.930

Flooding closed part of Route 202 in Peterborough, Route 122 and South Merrimack Road in Hollis, and widespread urban flooding in Nashua and Manchester. A mudslide closed a portion of Route 101 in Wilton. Minor to moderate flooding was observed on the larger mainstem rivers. The Merrimack River at Nashua crested at 23.5 feet at 8 am on the 17th (flood stage is 18 feet), while at Goffs Falls the Merrimack crested at 16.8 feet at 1 pm on the 17th (flood stage is 11 feet). The Contoocook River at Peterborough crested at 7.2 feet at 1 pm on the 16th (flood stage is 5.5 feet. The Souhegan River at Merrimack crested at 12.7 feet at 545 am on the 17th (flood stage is 9 feet).

Flood, Cheshire

When: April 16, 11:47 AM EST to 3:00 PM EST
Where: Cheshire County, Marlborough
Cause: Heavy Rain
Property damage: $100,000
Reported by: Amateur Radio
Coordinates: 42.900, -72.220

Several small streams in Marlborough were reported out of their banks.

What these are

Heavy Snow: Snowfall reaching the local warning threshold without the other hazards of a winter storm.
Flood: Flooding that develops more slowly than a flash flood: rivers leaving their banks, or water standing over land for an extended time.

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

The same day elsewhere

Every storm in New Hampshire in 2007 Every state in 2007 This day in weather history Warnings in New Hampshire, April 2007

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: 26735, 26736, 27742, 27745.