If April showers bring May flowers, what does May snow bring for June? Many locations in Northern Ontario are probably quite sick of snow at this point, but they may have more coming up. Thunder Bay, Nipigon,Geraldton, Moosonee have been getting some of the abuse with the last couple systems however this time the storm system approaching today will stay further south and east towards Northeastern Ontario. This means Timmins has a chance of snow tonight with a piece of energy broken off from the main system. North Bay and Sudbury have a chance of wet snow Saturday evening through to Sunday night with the main system. I don’t see much in terms accumulations mostly just mixing with the rain, but it could be possible in the overnight hours.
Here is a look Sunday morning as the low moves slowly through the province:
However Southern Ontario is not getting out of this one easy. Sunday morning through to Sunday night could see some wet snow further south. Not seeing any accumulations really just a possible mix with the showers. Here is the GFS model Sunday afternoon:
All this ugliness is the result of upper atmosphere blocking pattern that bigmt has been mentioning here and here. The incoming storm tonight will drop somewhere around 2 to 3+ inches of rain from Windsor to Ottawa from tonight until Saturday AM. After that the blocking pattern allows the storm to sit and spin in the area through to Wednesday when the storm eventually weakens and moves east.
This upper atmosphere blocking trough is one I have discussed before and is usually more typical of a winter pattern. The trough allows cold arctic air to filter in through Ontario for the next 5 days while the west stays well above normal. Many Ontario locations will see single digit highs (5c to 9c) temperatures when the normal is closer to 17c.
This below normal period was well noted from the past Euro weeklies and looks to extend to at least the long weekend, with maybe only the odd day at normal temperatures. Even towards the end of the month doesn’t look promising for well above normal temperatures just yet, but we should see this pattern eventually come to an end.
I would wait until at least the long weekend to plant anything outdoors.