One of the Driest Meteorological Winters on Record Across Much of the Prairies – Except Southern Alberta
*Note: these statistics do not include the early March 2018 winter storm across the Prairies, which was technically part of meteorological spring.
It was a very dry meteorological winter (DJF) across much of the Prairies this year. Widespread parts of southern Manitoba had less than 50% of normal precipitation. The same can be said for much of southern Saskatchewan, particularly in the Regina area, and for eastern Alberta.
The contrary was true in southern Alberta, where snowfall was well above average this winter. At Calgary International Airport, 77 mm of precipitation and 87 cm of snow were recorded between December 1 and February 28, making it the 7th wettest and 4th snowiest meteorological winter since 1884. Normal is only 29 mm of precipitation and 45 cm of snowfall.
The precipitation amounts and their rankings are presented with a great degree of uncertainty. The methods used to measure precipitation at Environment and Climate Change Canada’s stations have changed significantly over the period of record and have become automated in the past couple decades. We have found that the new automated methods tend to produce smaller precipitation amounts as compared to previous methods, especially when there are moderate to strong winds present. These differences in methods make it difficult to accurately and confidently compare this year’s data with historical data. Nonetheless, this past winter was certainly a dry one throughout much of the southern Prairies, despite the data issues.
Another issue with the weather data in the past couple decades has been the presence of missing observations. Missing observations have occurred quite frequently at some major stations. Often times, the missing data can be retrieved in raw data formats, but sometimes an estimate must be assigned. In the case of Regina, a snowstorm on December 4-5, 2017 of this past winter was not recorded. As a result, by comparing with nearby CoCoRaHS stations, we were able to assign an estimated precipitation amount of 3 mm for the event.
In southern Alberta, a lingering deeper-than-normal snow pack may result in a delayed start to spring with cooler than normal temperatures to start the month of March, before a warming trend occurs later in the month. In southern Saskatchewan and Manitoba, an early March winter storm has increased snow depth from near record lows, to fairly healthy levels. This increase in the snow pack will be helpful in replenishing moisture in the soil, but additional spring rains will be needed to fully recover from the dry conditions last summer.
For more information about the forecast for the upcoming summer/growing season, check out our official forecast here: https://www.weatherlogics.com/weatherlogics-summer-forecast-for-2018/.