effect. Despite this, there are usually two or more heavy snowfalls each winter which deposit at least accumulation, usually from powerful winter storms known as Alberta clippers, "Colorado Lows" or panhandle hooks that pick up moisture en route to the Great Lakes. These storms can produce strong easterly driven winds that fetch additional moisture from Lake Ontario. They frequently come with a volatile mix of snow, ice pellets, freezing rain and sometimes just ordinary rain, all of which can disrupt transportation, and in severe cases, interrupt power supply. A sustained freezing rain event occurred on December 22, 2013, plunging 30 percent of the city into darkness, some until after Christmas Day. Such storms can also produce large snowfall amounts, higher totals found in areas closer to Lake Ontario, sometimes falling over a series of days or weeks creating havoc. On January 13, 1999, after a series of snowstorms, then-Toronto mayor Mel Lastman called in the Canadian Armed Forces to assist with snow removal and clearing streets. Within twelve days, the downtown Toronto weather station at the University of Toronto (Trinity College near Queen's Park) recorded an average season's worth of of snow, much of it lake effect from Lake Ontario and a monthly record for January, but fell short of the snowiest month overall March 1870, with , of which fell over a five-day span. February 2008 set a record a snowfall record for the month with falling at the airport. The winter of 2007–08 brought accumulated seasonal snowfall totals of downtown and at the airport. The heavy winter snows, in combination with record rains during June–July of that year made 2008 the wettest year on the climate record with over of total precipitation. The largest single 24-hour and daily snowfall records occurred on December 11–12, 1944, when accumulated, with on December 11 alone. More recently on January 16–17, 2022, a blizzard dropped up to (in sections of Scarborough) of accumulated snow in the city, crippling public transportation, with most of it falling on the morning of January 17. The official storm total at Pearson Airport was On the opposite extreme, the winter of 2011–12 had the lowest seasonal snowfall total with only . March 2012 was the warmest March on record. The least snowfall in a calendar year was 2006, with only . The El Niño influenced winter of 2009–10 had , March 2010 recorded no measurable snow, the