'Wet slide' avalanche concludes wild week on Mount WashingtonBy JOHN KOZIOL
Union Leader Correspondent
January 16. 2018 9:21AM
After record cold followed by rain and record warmth, the tallest mountain in the Northeast wrapped up a wild week of weather Saturday with a “wet slide” avalanche in Tuckerman Ravine and the near disappearance of all snow from the summit.
Conditions were returning to “normalcy” on Sunday, when temperatures were right around zero and there was a forecast for snow on Tuesday, said Tom Padham, a meteorologist and observer at the Mount Washington Observatory.
On Jan. 6, the observatory tied a record low set on Jan. 5, 1959, when the thermometer atop the Rock Pile registered an air temperature of 38 below zero.
Combined with a wind measured at 106 mph, the resulting windchill was minus 97, ten degrees off the record of February 2004 when the air temperature was minus 44.
On Saturday, Mother Nature went the other way temperature-wise, with a high of 45, which set a daily record. The all-time monthly record is 48 degrees, on Jan. 13, 2013.
Between Jan. 6 and Saturday, the observatory had three days of temperatures in the 40s and got 2 1/2 inches of rain. What had been a snowpack of 26 inches was, as of Sunday afternoon, down to about an inch, Padham said.
Asked about the avalanche in Tuckerman Ravine, Padham said it was “absolutely because” of the warm temperatures and rain. He said the water ran beneath the snow, ultimately undermining the snow and bringing it and a significant amount of debris into the bowl of the ravine.
The Mount Washington Avalanche Center on Sunday said a refreeze had stabilized the snowpack, “but this avalanche serves as an excellent reminder of what heavy rains on snow can produce.”
At the observatory for five years, Padham called the recent 83-degree swing in temperature “pretty incredible.”
He said it also is unusual to have the top of Mount Washington bereft of snow.