March 2020 came in like a lamb but made an exit like a lion. A rather dry start to the month was followed by a stormier second half, including a burst of heavy, wet snow.

Chilly temperatures were in place as March began, but as we’ve seen since the first of the year, mild weather would take hold for most of the remainder of the first half of the month. The Arctic Oscillation remained in a positive phase but would dive into a neutral to negative state for the final week of the month.

For the better part of the winter the AO was positive, a record for February, and this is why the arctic air stayed put until almost a month into the spring season. The tail end of March brought about something else quite familiar to the spring season, high latitude blocking.

To point out how the cold air stayed trapped in Canada and Alaska, Fairbanks, Alaska never saw the temperature rise to 32 degrees during the winter for the first time in 21 years.

Alaska suffered through an extremely cold winter with February ranking as the 8th coldest of record. Alaska’s winter suffering brought much of the eastern half of the U.S. low heating bills and spring-like days during a typically cold time. It’s quite common to see the eastern U.S. see the opposite temperature regime that Alaska sees. This mild pattern brought the Nashua area a handful off beautiful spring days during the first half of March. Temperatures topped out at 73 degrees on the 9th, not a record, but a bonus for what we can see in early March.

March is known for flip-flopping and extreme weather and we would see a shift away from the mild temperatures during the final l0 days of the month as the AO became more neutral opening the door for some colder air to head south. The development of high latitude blocking only helped along the redistribution of the cold air supply far to our north.

High latitude blocking occurs during many springs for a time and shows up as high pressure in the upper levels across Greenland or Canada. The blocking pattern forces the jet stream to move south and can allow pockets of low pressure to develop south of the high pressure area creating some odd weather patterns. Weather systems can move from east to west for a time or stall for days bringing long stretches of cool, damp weather which us New Englander’s are familiar with at this time of year.

Temperatures for March averaged above normal for Nashua. The average temperature of 39.3 degrees was 4.7 degrees above normal. March was the 12th mildest of record out of 127 years of data.

Precipitation was sparse during the first half of March but things ramped up during the second half of the month as storminess became more frequent. The southward shift of the jet stream brought much more activity our way boosting precipitation totals.

The months’ total of 3.71 inches was shy of normal by 0.65 inches. March ranked as the 78th driest out of 137 years of record. The largest precipitation event was 1.29 inches recorded on the morning of the 24th.Other than a few flurries on a couple of days, snow was non-existent until the storm of the 23rd into the 24th. This storm brought a thump of heavy, wet snow to the area.

Snow totals were in the 4-7 inch range around the lower Merrimack Valley and resulted in some power outages as trees and branches brought down some power lines. Nashua’s snow total for the month was 3.5 inches, 7.2 inches below normal. March ranked as the 31st least snowy out of 111 years of snowfall data.

For the season Nashua has seen 43.9 inches, a deficit of 10.2 inches. While we are moving deeper into spring the threat of snow is not yet over. A normal April usually sees about 2 inches of snow in Nashua, but snowfall is not consistent from year to year.

April 1982 brought Nashua a major mid-winter type blizzard from the 6th into the 7th. 12-18 inches of snow fell and was blown around by high winds gusting over 50 mph producing big drifts. Temperatures were in the teens during this storm and record low temperatures were set during daylight hours. April’s weather is generally known for being cloudy, damp, and chilly at times. Snow is not uncommon during April but amounts are usually not heavy and occur mostly during the first half of the month. On average April and May are the cloudiest months of the year across New England due to a high occurrence of easterly winds off the cold, moist Atlantic Ocean.

Wildfires can be a potential problem during April. Before the new seasons’ vegetation comes alive there exists a great amount of dry leaves and grass that can easily catch fire on some of the sunny, dry days that can occur this time of year.

Warm weather during April typically comes in short spurts of a day or two. During these periods temperatures can shoot up into the 70s and 80s. Don’t get used to it because a wind switch into the east or southeast can send temperatures tumbling in a hurry.

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March Facts and Feats dating back to 1884

March 2020 Average Temperature

39.3 degrees, 4.7 degrees above normal

Mildest March

2012, 43.5

Coldest March

1906, 26.3

All-time March High

85, Mar. 29, 1998, and

March 30, 197.

March 2020 High

73, March 11.

All-time March Low

18 below, March 6, 1948

March 2020 Low

17, March 1

March 2020 Precipitation

3.71 inches, 0.65 inches below normal

2020 Annual Precipitation to date

9.41 inches, 1.67 inches below normal

Wettest March

2010, 11.04 inches

Driest March

1915, Trace (no snowfall)

March 2020 Snowfall

3.5 inches, 7.2 inches below normal

Snowiest March

1956, 45.7 inches

2019-20 Season Snowfall

to date

43.9 inches, 10.2 inches below normal

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