I’ve received several emails asking when we’ll be doing our in-depth review of this summer’s weather. For those of you who are interested, you will have to wait for one more issue. As part of my seasonal review, I also take some time to look ahead to see what the long-range forecasts call for next season. Since it looks like this summer’s review will take up a fair bit of space, we are going to take our first look ahead to see what the forecasters predict now for this fall and winter.
Before we dive directly into the forecasts, I thought it would be a good idea to look at what’s happening with some of the large-scale climatic features that help drive overall weather patterns.
To begin, we’ll look at the planet as a whole. July’s global temperature, as measured by NOAA, came in as the fourth warmest on record. NASA ranked July as the third warmest and the University of Alabama Huntsville ranked July as the fourth warmest in its 40-year record of global satellite-measured temperatures. Year to date, 2018 is also the fourth-warmest year on record and, barring some climate-altering event, it looks as though the five warmest years globally will all have occurred over the last five years.
Does this mean it is going to be a warm fall and winter across our region? No, not necessarily. What it does mean is that our atmosphere is continuing to be warmer than average and will help increase the odds that we will see warmer-than-average temperatures.
Next, it looks like the extent of Arctic sea ice will end up falling somewhere between the fourth- and ninth-lowest amounts on record. Exactly how lower levels of summer sea ice in the Arctic impact our weather is just beginning to be understood and there is still much research to be done. We now know these lower levels of ice are changing our mid-latitude weather patterns; we just don’t know exactly how. This is creating a bit of a wild card when it comes to long-range weather forecasting.
The last piece of the big-picture puzzle is El Niño. El Niño, the warming of a large part of the Pacific Ocean, and La Niña, which is the cooling, can have significant impacts on our weather, especially in the winter. There is an El Niño watch now in effect, with NOAA forecasting a 60 per cent chance of El Niño conditions developing this fall and a 70 per cent chance of one developing by the winter. El Niño often brings our region warmer-than-average winters.
OK, now that we have some background on what is going on, let’s look at some of the long-range forecasts. The Old Farmer’s Almanac calls for a cool and dry fall, followed by a cold and snowy winter. February is the only warmer-than-average month, with January forecast to be the coldest. It forecasts both December and January seeing well-above-average snowfall. It looks as though the Canadian Farmers’ Almanac also predicts a cooler-than-average fall as it mentions cold or colder weather several times. It also looks like it calls for above-average amounts of precipitation as it mentions wet, stormy, and showery weather several times. It then predicts the cold weather will continue into the winter, with below-average temperatures and above-average snowfall.
Moving on to Environment Canada’s probabilistic forecast, it calls for above-average temperatures this fall and early winter, trending toward average temperatures for the latter part of winter. As for precipitation, Environment Canada’s models always seem to lean toward near-average amounts. Environment Canada’s other long-term weather model, the CanSIPS model (Canadian Seasonal to Inter-Annual Prediction System), calls for a cooler-than-average start to fall, with a return to warmer-than-average conditions which are then forecast to last right through the winter. This model also calls for near-average amounts of precipitation.
While NOAA’s long-range forecast maps magically stop right at the Canada-U.S. border, I think we can reliably extrapolate its forecast northward into southern and central Manitoba. NOAA is on the same page as Environment Canada and predicts above-average temperatures this fall and winter, with a good chance of well-above-average temperatures in the winter. Its precipitation forecast calls for near-average amounts, with western regions having the best chance of seeing below-average amounts.
Lastly, my forecast. At this point I am leaning toward a warmer-than-average fall and winter. For those of you who follow my long-range forecasts, you’ll know that precipitation forecasts are really tough, as one storm can significantly change things. So, I am also going to play it safe for now and predict near- to slightly below-average amounts of precipitation both for this fall and winter. Now as usual, we’ll have to see what Mother Nature decides to throw our way.