The winter of 2015-16 will go down in history as one of the mildest Saskatchewan has seen in the past 50 years.
However, it wasn’t the warmest, says Virginia Wittrock, a climate research specialist with the Saskatchewan Research Council in Saskatoon.
That title still belongs to the winter of 2011-12.
“Yes, last winter was very warm,” Wittrock said. “But it wasn’t the warmest. It was actually the fourth warmest in the last 52 years for our climate station.”
The SRC climate station is based at Saskatoon and has been collecting climate data from the same location since the early 1960s.
Winter climate data is collected during a three-month period that includes December, January and February.
The maximum average temperature during the 91 days of winter 2015-16 was -4.8 C.
The highest maximum average winter temperature ever recorded by SRC’s Saskatoon station was -1.9 C in 2011-12.
The second and third warmest winters on record were 1986-87 and 2005-06.
Last winter was tied for first in terms of average minimum temperatures with 2011-12 at -12.6 C.
Wittrock said the temperature in Saskatoon fell below -30 C only once last winter — to -31 C on Jan. 16.
The mild winter temperatures were also reflected in warmer soil temperatures.
The SRC monitors daily soil temperatures at various depths during the winter, taking the measurements daily at 9 a.m.
The lowest value recorded was -4 C in mid-January at the five centimetre depth, which is usually the coldest.
That compares with 2014-15, when the coldest temperature at five cm was -9 C.
Wittrock said the soil temperatures recorded this winter were a bit of a surprise, given that warmer temperatures are more likely to occur under a heavy snow pack.
“We didn’t have a big snow pack this year,” she said.
“The deepest it got was 14 cm and it was gone by March 11-12, so the snow pack wasn’t very deep, it wasn’t a very long (snow pack) and the soil temperatures didn’t get very cold.”
The winter of 2015-16 also ranks as the 16th driest in the last 52 years, Wittrock said.
“We got 32.1 millimetres of precipitation last winter and we usually get 38.2 mm.”
The mild winter and warm soil temperatures could have a noticeable impact on insect populations and soil borne pathogens this year and affect farming and gardening operations during the coming growing season.
Saskatoon had 24 days with maximum daily highs above 0 C between Dec. 1, 2015, and Feb. 29, 2016. The temperature normally gets above 0 C for only 16 or 17 days during a Saskatoon winter.
Saskatoon had 17 days with daily minimum temperatures below -20 C last winter, compared to 37 days normally.
Monthly and annual temperature and precipitation summaries compiled by the SRC can be viewed online at src.nu/crsdata.