Snow Depth Days
of the Northeast: 2008-2009

The season in review

The explosive start of the 2007/2008 season didn't happen this year. Still, December brought over two feet of snow in 9 days with snowy weather, with most falling between the 19th and 21st, but most melted just after Christmas. January brought two and a half feet with three storms over 6". For the season to date this was more snow than many years. Southern New England saw more snow than in all of last year. There was no January thaw, the high for the month was just 38 and the dew point never went above freezing. There was plenty of cold, the low of -17 was the lowest I've record (by 4 degrees) in my five years of records. February had near average temperatures, but much less snow than average, just under a foot. Still, the minimum snow on the ground was never less than a foot and the SDDs for the month exceeded the seasonal total for half the years in my record.

Daily/Monthly Data

The following table summarizes the snow fall and depth days from sites that are posting that data on local weather observations mail lists and a couple others. If people also prepare Web pages for daily information for their site, I'll include links to them. Cells under the "snow" column are the snowfall for the site in that month, under "SDD" are the depth days for the month.

Location October November December January February March April May
Snow SDD Snow SDD Snow SDD Snow SDD Snow SDD Snow SDD Snow SDD Snow SDD
Collinsville CT
Ashland MA 26 86 21.5 172 7 72
Fairhaven MA 19.1 50 6.6 67 4.1 14 5.8 21
Groveland MA
Marlboro MA 29.7 78.5 22.9 246.5 6.3 158.5 12.3 46.5
Pepperell MA 0.2 0 30 118.5 28.1 379 9.2 349 18.3 132
Poland Spring ME 0.4 0 24.7 129 29.2 354 26.3 496
Bow NH 32.2 145 35.7 496 17.6 616 20.3 567
Penacook NH 26.1 111 30.6 376 11.3 488 12.8 307
Charlestown RI 17.4 44 17.2 132 3.6 44 11.6 34
Woonsocket RI 23.2 64 19.6 210 6.1 68 10.2 42
Mt. Mansfield VT 6 37 30.5 232 55.1 853 48.4 1601 31.5 2008 15.5 2458 21.5 2429 0 617

2008-2009 season to end of last month

The persistence quotient is lower than the ultimate value if there is still snow on the ground at the site. This data will be updated each month.

Location Snowfall Depth Days Persistence
Collinsville CT 0 0 ...
Ashland MA 54.5 330 6.1
Fairhaven MA 35.6 152 4.3
Groveland MA 0 0 ...
Marlboro MA 71.2 530 7.4
Pepperell MA 85.8 978.5 11.4
Poland Spring ME 80.6 979 12.1
Bow NH 105.8 1824 17.2
Penacook NH 80.8 1282 15.9
Charlestown RI 49.8 254 5.1
Woonsocket RI 59.1 384 6.5
Mt. Mansfield VT 208.5 10235 49.1


Name Location
Dennis Bollea Fairhaven MA
A Cadoret Woonsocket RI
Wayne Cotterly Poland Spring ME
Paul Hansen Marlboro MA
Jim Hilt Bow NH
Andrew Plona Collinsville CT
Jot Ross Ashland MA
Chris Seeber Charlestown RI
Rick Tracy Groveland MA
Paul Venditti Pepperell MA
Ric Werme Penacook NH


Jim Corbin, a meteorologist from Rhode Island, proposed the concept of both snow depth days and the persistence quotient, but he didn't have good names for them.  After a bouncing around various ideas, I came up with Depth Days.  It seems to fit into colloquial speech well, e.g. "When mired in the Depth Days of February, she thought fondly of the Dog Days of August." Of course, none of us snow lovers would ever think that. I picked Persistence Quotient while putting this page together, we'll see how it wears with time.


I think depth days is a great statistic, and I'm surprised that it is catching on slowly outside of the NE Weather Spotters mail list. I never expected that the NWS would embrace it quickly, but I had hoped that TV meteorologists would start using it, in monthly summaries, if nothing else. It would be nice if ski areas would use it, but they may not wish to if they are not likely to be #1 consistantly. (And if only one area reports depth days, it would not be a good comparative statistic.) The University of Vermont has graphs of snow depths at Stowe through many seasons.

Last update: 2009 December 13
Ric Werme

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