Gulf of Maine climate quarterly impacts and outlook: March 2015

Winter temperatures (averaged over December, January, and February) ranged from near normal in Nova Scotia to 3°C (5.4°F) below normal in New Hampshire and Massachusetts. December was quite warm, with most areas seeing temperatures 2°C (3.6°F) to 4°C (7.2°F) above normal. The three states ranked this December among their top 11 warmest. Colder conditions returned in January, with temperatures ranging from near normal in Nova Scotia to 3°C (5.4°F) below normal in the states. February was an extremely cold month across the region, with temperatures up to 8°C (14.4°F) below normal. The three states had their second coldest February on record.

Temperature and precipitation normals based on 1981-2010.

Winter precipitation (accumulated during December, January, and February) ranged from near normal to 200% of normal, with the greatest amounts in eastern New Brunswick. December was a wet month regionwide. Precipitation generally ranged from 125% to 275% of normal, with the wettest areas in eastern New Brunswick. Maine, New Hampshire, and Massachusetts ranked December 2014 among their top 20 wettest. Precipitation varied in January, with amounts ranging from 50% of normal in northern Maine and northern New Brunswick to 150% of normal in Nova Scotia. February precipitation ranged from 25% of normal in northern Maine to 200% of normal in eastern Nova Scotia.

Canada and ocean precip data: Canadian Precipitation Analysis.

U.S. precipitation data: interpolated station data.

Warm sea surface temperature anomalies that were present throughout the region in fall persisted in most areas through winter. Temperatures (averaged over December, January, and February) were up to 1°C (1.8°F) above normal over the entire region except in the shallowest areas near shore. Strong region-wide warm anomalies in December weakened only slightly in January. These warmer than normal sea surface temperatures may have helped intensify storms during winter. The three-month winter average hides the fact that in February, ocean cooling created negative anomalies over shallow coastal areas, the Jordan Basin, the northern Bay of Fundy, and the Scotian Shelf in response to the cold air temperatures.

Sea surface temperature anomalies based on 1985-2014. Mean SST anomalies from NOAA AVHRR data. Credit: University of Maine School of Marine Sciences and NERACOOS

Snow totals varied widely in December, but in late January and February, a persistent trough over eastern North America allowed Arctic air and numerous storms to move through the Gulf of Maine region. With back-to-back storms and persistent cold, snow accumulated quickly (see daily snowfall accumulation chart). Snow removal was difficult, especially for cities such as Boston, MA, and Saint John, NB, which each hauled away at least 20,000 truckloads of snow from their streets. Some municipalities in the U.S. received exemptions to dump snow directly into bodies of water, a practice not normally permitted. The cost of snow removal made this winter the most expensive year ever for some areas.

The snowstorms caused frequent school and business closures, thousands of flight delays and cancellations, and power outages, while the weight of the snow caused roofs to collapse. It was estimated that the snowstorms cost Massachusetts’ economy at least $1 billion. The snow also contributed to many accidents, including one of the largest chain-reaction crashes in Maine’s history on February 25. Frigid temperatures resulted in water main breaks and frozen pipes.

Ski resorts benefited from the cold and snow, though. Sugarloaf, in Carrabassett Valley, ME, anticipated its best season ever with respect to traffic and revenue. As of mid-February, the resort had seen a 10% increase in total skier visits and a 14% increase in revenue since last year.

For March through May, Environment Canada is predicting an increased chance of below-normal temperatures for New Brunswick and northern Nova Scotia, an increased chance of above-normal temperatures for a small portion of southern Nova Scotia, and equal chances of above-, near-, or below-normal temperatures elsewhere. Greater than normal snowpack, record ice cover on the Great Lakes, and extensive sea ice in Hudson Bay, the Gulf of St. Lawrence, and waters near Newfoundland and Labrador contributed to the forecast for below-normal temperatures.

NOAA’s Climate Prediction Center is forecasting equal chances of above-, near-, or below-normal temperatures from March through May for Maine, New Hampshire, and Massachusetts.

(Caption: Environment Canada map produced on February 28.)

The potential for river flooding during spring is near to above normal for Maine, New Hampshire, and Massachusetts, according to NOAA. Across eastern New England, the potential for spring river flooding is above normal. Snow water equivalents are above normal for this time of the year in that area. If the region gets a period of warm weather combined with heavy rainfall events, then the possibility of moderate flooding may occur. In northern New England, extensive river ice increases the risk for ice jam flooding. Minor river flooding is possible across the rest of New England.

Heavy rainfall can cause river flooding at any time, even in areas where the flood potential is considered low. Local river forecasts can be found the Northeast River Forecast Center.