Ice Storm and Heavy Snow in New Hampshire, March 6 to 7, 2011

Name: Ice Storm and Heavy Snow in New Hampshire, March 6 to 7, 2011
Start: 2011-03-06T14:00
End: 2011-03-07T15:00
Location: New Hampshire

March 6 to 7, 2011 · NWS GYX · 5 events in 5 counties and zones

On Saturday morning, March 5th, a frontal system was located over the Ohio and Mississippi River Valleys. Ahead of the front, south to southwest winds ushered in some very mild air.

Where it happened

Every event with a place to put it; 5 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: $718,000
Crop damage: None recorded
Events: 5

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.

On Saturday morning, March 5th, a frontal system was located over the Ohio and Mississippi River Valleys. Ahead of the front, south to southwest winds ushered in some very mild air. Temperatures across most of southern and central New Hampshire warmed into the lower 50s during the day and remained well above freezing Saturday night. At 7 AM Sunday, temperatures were in the upper 40s to lower 50s across the state. By Sunday morning, March 6th, the front had moved east to the Appalachians and the strong southerly flow ahead of the system continued to bring mild temperatures and tropical moisture northeast from the Gulf of Mexico and southern Atlantic Ocean. Temperatures Sunday climbed into the middle 50s across the state. An area of low pressure began to develop over the southeastern states Sunday and then moved northeast along the frontal boundary Sunday night and Monday as it intensified rapidly. Light rain, associated with the approaching cold front began to fall Sunday morning. The precipitation became heavy by late afternoon as the intensifying area of low pressure approached New Hampshire from the south. At the same time, colder air started funneling into the state from the north and changed the rain to snow across Coos County. As the colder air continued to move southward late Sunday afternoon and evening, the rain changed to freezing rain across Grafton County and the higher elevations of Sullivan and Merrimack Counties. Across the state, heavy snow, freezing rain and rain continued through the night and finally ended early Monday afternoon, March 7th. In addition to the precipitation, strong and gusty winds developed across the region Sunday night and continued Monday. Winds gusted to about 20 to 25 mph across much of southern New Hampshire during the storm with gusts of about 30 to 45 mph as the storm moved east Monday afternoon.

Across northern New Hampshire, snowfall accumulations from the storm ranged from 8 to 22 inches. In Grafton and Sullivan Counties, ice accretions of inch were reported, although local amounts were likely higher. This ice, in combination with the wind, brought down trees and tree limbs across Grafton and Sullivan Counties leading to numerous power outages and more than $700,000 in damage.

Rainfall amounts across the southern part of the state were generally in the 1 to 3 inch range, with locally higher amounts. In addition, melting snow, due to the mild temperatures, contributed to the runoff from the storm. The rainfall and melting snow caused river levels to rise which caused river ice to break and move downstream. Several breakup ice jams occurred, with the most notable jams being in West Claremont on the Sugar River and in Plymouth on the Pemigewasset River. Other jams occurred on the Baker and Contoocook Rivers. These ice jams remained in place for several days.

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 6, 4:19 AM EST, 9 hours 41 minutes earlier.

Area forecast discussion, Mar 6, 4:19 AM EST, 9 hours 41 minutes before

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Hazardous weather outlook, Mar 6, 3:22 AM EST, 10 hours 38 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GRAY ME
322 AM EST SUN MAR 6 2011

MEZ007>009-012>014-NHZ001>007-070830-
NORTHERN OXFORD-NORTHERN FRANKLIN-CENTRAL SOMERSET-SOUTHERN OXFORD-
SOUTHERN FRANKLIN-SOUTHERN SOMERSET-NORTHERN COOS-SOUTHERN COOS-
NORTHERN GRAFTON-NORTHERN CARROLL-SOUTHERN GRAFTON-SOUTHERN CARROLL-
SULLIVAN-
322 AM EST SUN MAR 6 2011

...WINTER STORM WARNING IN EFFECT FROM 4 PM THIS AFTERNOON TO 11 AM
EST MONDAY...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN MAINE...CENTRAL NEW
HAMPSHIRE AND NORTHERN NEW HAMPSHIRE.

.DAY ONE...TODAY AND TONIGHT.

PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE
INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS.

   WINTER STORM WARNING.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY.

PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE
INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS.

   WINTER STORM WARNING.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS ARE ENCOURAGED TO CALL OR RADIO IN SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

MEZ018>028-NHZ008>010-013-014-070830-
INTERIOR YORK-INTERIOR CUMBERLAND-ANDROSCOGGIN-KENNEBEC-
INTERIOR WALDO-COASTAL YORK-COASTAL CUMBERLAND-SAGADAHOC-LINCOLN-
KNOX-COASTAL WALDO-MERRIMACK-BELKNAP-STRAFFORD-INTERIOR ROCKINGHAM-
COASTAL ROCKINGHAM-
322 AM EST SUN MAR 6 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN MAINE...CENTRAL NEW
HAMPSHIRE AND SOUTHEASTERN NEW HAMPSHIRE.

.DAY ONE...TODAY AND TONIGHT.

HEAVY RAIN AND WARM TEMPERATURES WILL COMBINE TO INCREASE RUNOFF
FROM MELTING SNOW AND RAINFALL SUNDAY NIGHT. SOME MINOR FLOODING
IS POSSIBLE...ESPECIALLY IN URBAN AREAS WHERE DRAINAGE IS POOR.
SNOW PILES FROM PREVIOUS STORMS MAY BLOCK STORM DRAINS AND CAUSE
FLOODING OF LOCAL ROADS.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS ARE ENCOURAGED TO CALL OR RADIO IN SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

ANZ151-153-070830-
PENOBSCOT BAY-CASCO BAY-
322 AM EST SUN MAR 6 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CASCO BAY AND PENOBSCOT BAY.

.DAY ONE...TODAY AND TONIGHT.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS ARE ENCOURAGED TO CALL OR RADIO IN SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

ANZ150-152-154-070830-
STONINGTON ME TO PORT CLYDE ME OUT TO 25 NM-
PORT CLYDE ME TO CAPE ELIZABETH ME OUT TO 25 NM-
CAPE ELIZABETH ME TO MERRIMACK RIVER MA OUT TO 25 NM-
322 AM EST SUN MAR 6 2011

...GALE WARNING IN EFFECT FROM 7 PM THIS EVENING TO 7 AM EST
MONDAY...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE COASTAL WATERS FROM CAPE
ELIZABETH ME TO MERRIMACK RIVER MA...THE COASTAL WATERS FROM PORT
CLYDE ME TO CAPE ELIZABETH ME AND THE COASTAL WATERS FROM
STONINGTON ME TO PORT CLYDE ME.

.DAY ONE...TODAY AND TONIGHT.

PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE
INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS.

   GALE WARNING.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY.

PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE
INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS.

   GALE WARNING.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS ARE ENCOURAGED TO CALL OR RADIO IN SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

The radar

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

Open the radar archive at this moment

Event by event

3 ice storm, 2 heavy snow. Local standard time, as filed.

Heavy Snow, Northern Coos

When: March 6, 2:00 PM EST to March 7, 3:00 PM EST
Where: Northern Coos forecast zone
Reported by: Official NWS Observations
Coordinates: 44.690, -71.305 (the zone’s center; the record gives no point)

Heavy Snow, Southern Coos

When: March 6, 2:00 PM EST to March 7, 3:00 PM EST
Where: Southern Coos forecast zone
Reported by: Official NWS Observations
Coordinates: 44.690, -71.305 (the zone’s center; the record gives no point)

Ice Storm, Sullivan

When: March 6, 2:00 PM EST to March 7, 3:00 PM EST
Where: Sullivan forecast zone
Property damage: $400,000
Reported by: Emergency Manager
Coordinates: 43.361, -72.222 (the zone’s center; the record gives no point)

Ice Storm, Southern Grafton

When: March 6, 2:00 PM EST to March 7, 3:00 PM EST
Where: Southern Grafton forecast zone
Property damage: $159,000
Reported by: Emergency Manager
Coordinates: 43.941, -71.820 (the zone’s center; the record gives no point)

Ice Storm, Northern Grafton

When: March 6, 2:00 PM EST to March 7, 3:00 PM EST
Where: Northern Grafton forecast zone
Property damage: $159,000
Reported by: Emergency Manager
Coordinates: 43.941, -71.820 (the zone’s center; the record gives no point)

What these are

Heavy Snow: Snowfall reaching the local warning threshold without the other hazards of a winter storm.
Ice Storm: Freezing rain accumulating a quarter inch or more of ice, or less where it caused significant damage.

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

The same day elsewhere

Every storm in New Hampshire in 2011 Every state in 2011 This day in weather history Warnings in New Hampshire, March 2011

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 2026-09-30. Each event’s entry at NCEI: 283795, 283797, 295044, 295045, 295046.