Nice to get a good rain the last couple days. Here are some rain totals since Friday:

  • Ottawa: 44.4 mm
  • Toronto: 28.2 mm
  • Belleville: 34.8 mm
  • Kingston: 19.1 mm
  • Montreal:  36.3 mm
  • Bancroft: 59.7 mm
  • Hamilton: 22.2 mm
  • London: 38 mm
  • Sault Ste. Marie: 17.4 mm
  • North Bay: 27.3 mm

Many models had been showing this low pressure moving in and developing with heavy rain with all the humidity hanging around.  Models have been wrong multiple times this summer with these fronts and they end up being only scattered convective storms, so it was hard to predict.  Looks like Central Ontario into the Ottawa Valley and Quebec got some good steady rain with downpours and thunderstorms.  It was scattered around Toronto but some good downpours in the area as well as the London area since Friday.  Not enough to end the drought conditions but certainly better than nothing.
So,  let’s get into the fall forecast (September/October/November).  Overall what has been happening this summer will continue for some time into this fall.

First let’s take a look at the average temperatures this fall from 3 long range models, CFS, NMME, JAMSTEC (the IMME seems to be down lately):

Fall long range temps

Only one model (CFS) shows normal temperatures in the east with warmth in the west.  However most models predict above normal temperatures for most of the country.  Expect that September through October’s general pattern will be warm while my predictions are that November through to December will only be slightly above normal. This doesn’t meant that everyday will be hot, just the general pattern on the average will be above normal.

Next here is the long range precipitation:

Fall Long Range percp

Again only the CFS shows slightly above normal precipitation for the east while the others are dry for Ontario and Quebec while both coasts are wet.  My predictions are for dry conditions in Ontario, with less rainy days than normal, likely right through to late November or mid December before we start to see more low pressure systems make there way through here.  This means that the fall leaf colour will not be as spectacular this year, as many trees are already stressed and dropping their leaves with a more yellow dead colour. What we can hope for is that there is a chance of higher than normal tropical and hurricane development.  Often left over hurricanes make there way into Southern ON, however the general long range pattern has them hitting the East Coast.

Here is my breakdown for the regions:

BC West coast:  Expect slightly warmer temperatures and trend wetter than normal through the fall.

The Prairies: Expect things to get warmer than normal for Manitoba and Saskatchewan, and turning drier than normal in the north around Edmonton and normal in the southern section.  Cities like Calgary, Edmonton, Regina, and Winnipeg sure could use a break from the rain they got this summer.

Ontario: All of Ont can expect a warmer than normal fall and dry conditions. Potential for systems from the tropics will be the best option for rain.  With the Great Lakes being warmer than normal if we do get the odd Arctic outbreak in late October early November there could increased Lake Effect snows in the typical regions.

Quebec:  Southern Que can expect the warm and dry conditions as well. The closer to the East coast things should be near normal.

East Coast: Expect the area will be normal trending to colder than normal and Newfoundland and extreme Nova Scotia coasts can expect increased tropical systems moisture.  Otherwise it will dry to possibly near normal.

My initial thoughts for December is it should eventually turn colder and I think there will be more opportunity for snow storms than last year.  Winter Forecast will come later in September or October.