We were pretty close with our spring 2018 forecast with the colder and wetter season, We also got close with the timing of the rapid warm up. By the end of April temperatures peaked in the high 20s. May finished off as either the warmest on record or in the top 3.
The consensus on summer 2018 is that it could be significantly hotter than later year.
Overall summer is expected to be much hotter than normal, with relatively less strong heat along the foothills in addition to closer to normal rainfall. The northern part of the province could be extremely dry in July and August. Temperatures potentially flying past the 35°C degree mark. Thunderstorm activity could be the lowest in a decade for East Central and Northern Alberta. More elevated convective activity can be expected in the northern foothills.
June: The closest to normal month of Summer 2018, A modest amount of rainfall and near normal temperatures overall for the first 2 or 3 weeks but growing hot toward the end of the month. Thunderstorm activity will be low save for a few outbreaks mid month.
July: Becoming very hot, especially in the 2nd half of the month. Temperatures could surpass 35°C in many areas and near 40°C in the south. The foothills should be able to stay clear of that mark Red Deer being the largest city to avoid passing 35°C. Rainfall could be nearly zero in the some parts of the province.
August: Very hot conditions continue or amplify. Temperatures could surpass 35°C in Edmonton(esp Blatchford) and Calgary. A break in the drought conditions. A note is that Edmonton surpassed 35°C in 1998 and in 2008. Dense forest fire smoke might prevent such extreme heat much like it did last year and in 2015 (we have a post about that from last year).
Thunderstorm forecast: Summer 2018 has the potential to be the quietest in a decade due the a lack of moisture and persistent ridging. However the northern foothills could see an active storm season which could spark copious forest fires.
Overall we are seeing a cooler and wetter spring overall in Alberta. With a rapid warm up as early as late April.
Winter was colder and near to wetter than average and these conditions are likely to continue at least half way into spring.
March(very cold and wet): March was so winter like I’m going to go and say it counts more as part of the Winter.
April(cold and wet): Cold and wet for most of the province, the exception being the more northern regions being slightly drier than normal. Major snowstorms will track across the province maintaining the winter look for much of the month.
May(Warm and wet): First signs of both spring and summer, Rapid temperature rise will likely make spring 2018 very very short weather wise. An example year would be 2013. This also spells worry as the snows at higher elevations will likely stay until the heavier June moisture builds. The quick increase in temperature and late arrival of warm temperatures should keep the fire risk way down. Flood risk very high
June(warm and wet): Short, but intense startup to the thunderstorm season sparked by high heat and humidity. Very high flood risk. Higher than normal humidity.
Most seasonal models show a large ridge of high pressure stamping down on thunderstorm activity as the summer heats up. Long periods of hot,dry and storm-less weather in July, August, and September. Summer may turn out much drier than normal even after early moisture
After a fall that averaged near to above normal quenched by November cold and snow. Winter 2017/18 is likely to have even more temperature swings, more than we saw last year with swings from the minus 30s to near the all time highs in mere weeks.
Winter should finish off with near to below normal temperatures and generally lower snowfall outside of the rocky mountains and foothills.
The Main factor in play this season is a moderate La Nina, and favors below normal temperatures but may be moderated by other factors such as the AO, PDO, and NAO
While December is very mild; January will likely see the coldest temperatures of the season, possibly into February and the stubborn cold May linger well into March making for a late spring.
December: Well above normal temperatures and very dry. A small amount of snow might save Edmonton and Calgary from a brown Christmas. It may only be 5cm or so but it’s enough to make Christmas white
January: Very cold at times, remaining dry.
February: chance of a thaw but overall near to colder than normal. Snowfall close to normal.
Real significant snowfall might not come until February or March as the dominant air masses in play are very low in moisture content.
The risk of blizzards is higher than a normal winter as the chance of high winds is higher.