Has spring arrived in Montreal?

Lac St. Louis remains locked in ice February 28, 2018. However, with above-normal temperatures during the last two weeks and more mild air expected for the next two weeks, the ice should begin to thin and break up soon. (ValleyWeather Photo)

Meteorological winter will come to an end today, February 28. In Montreal, it was an interesting winter, to say the least, but is it over? February started off cold and snowy, with expectations of that weather lasting the entire month and well into March. Mother Nature, however, had a different plan, with a large warm ridge of high pressure dominating eastern North America. A persistent western trough managed to keep the cold air locked in place across the Prairies, Alberta and B.C. For Montreal, the average high for February was -0.2C, well above the normal of -3.2C. The temperature was above the freezing mark on 15 of the 28 days. In the last two weeks, daytime highs have been anywhere from 5 to 15 degrees above normal on most days. The two factors keeping our highs lower than they may have reached were the 207cm of snow that fell on Montreal from December through early February and the frozen St. Lawrence River.

Is the warm weather here to stay?  The short answer: yes. Looking into our "crystal ball", no frigid air is expected for at least the next two weeks. At that point, being well into March, the angle of the sun is increasing, making it rather difficult for arctic air to become established.

Just how warm has it been overall this February? Well in Greenland, February high temperatures have been running well above normal. At Cape Morris Jessup, in the high Arctic region of northern Greenland, the temperature has been above freezing for 61 hours this winter. The Arctic winter runs October to March, with much of the region in complete darkness. The 61 hours establishes a new record, smashing the old record of 16 hours set in 2011. The warm weather included 24 consecutive hours above freezing on February 20th and a high of 6C (43F) on February 24. This shows us just how little cold air is available across eastern North America. These numbers should be a real concern to all of us. They are startling. While above-freezing winter temperatures do occur, on average, once a decade at this location, this is the second time in the last three years, and never for such an extended period. Arctic sea ice is melting faster than anyone expected.

With all of this information taken into account, and peeking at the models over the next few weeks, spring may have indeed arrived in Montreal. However, that does not rule out a quick-hitting storm or two. As we are all well aware, historically, the largest snowstorms in Montreal have occurred in March and even into the early part of April.