As noted in my last blog post a couple small systems will move through Ontario this week into the weekend.  These should remain all rain from locations in North Bay and Sudbury south into Southern ad Eastern Ontario, including tonight’s small system which was on the models more for Wednesday morning but should wrap up overnight and another system coming Thursday.

The strongest of the storms will be the Friday-Saturday storm which should bring mixing and freezing rain around Sault Ste Marie to Sudbury – North Bay down towards the Ottawa Valley. However, everybody should quickly change over to rain (some northern locations like the Sault should turn back to snow).  Southern Ontario will remain all rain. Here is the look from today’s GFS:gfs_mslp_pcpn_frzn_us_14

Behind this storm conditions will return closer to normal as our little spring tease comes to a close.  However, be warned, many of the models have the Great Lakes region in their targets for the next 15 days, as many active systems move in and out.  This is because we have returned to the cold west, strong, warm SE ridge conditions in the East that we have battled with all winter, particularly in late December into January.  Here is the description I provided in a previous December blog post:
“The upper level patterns wants to return to the pattern back in late November early December with upper level atmosphere block trough out west,  and the Southeast Ridge in the east.  These upper atmosphere conditions are common in a La Nina type winter like ours, and force storms from the west to our area.  The jet stream (upper level steering winds) typically takes the path of least resistance, and goes around these areas. The below is an example of what occurs:”trough-ridge-map
Unfortunately too big and strong of a Southeast Ridge can cause storms to really cut west and bring rain and warmth to our region, like the below:too-big-ridge
You can also see this in the upper atmosphere and temperature forecast below for the next 15 days (BTW if you are headed to Florida in March, you are in for a treat, conditions look warmer than normal):Day10.PNG
This means many chances for either snow or rain are in the future for locations across Ontario.  It will depend on how much muscle the SE ridge wants to flex as to who gets rain or who gets snow.  As we return to closer to normal temperatures it wouldn’t take much for somebody to get a pretty major snow storm in the next 2 weeks.  Although given the time of year, as we begin to loose a lot of the colder air, we should see many of the storms become marginal in terms of snow/rain lines.  The snowfall’s ability to stick around after a storm will be numbered, especially for southern Ontario.
I still believe the worst of the winter conditions are behind us, but be on guard for more winter weather through to mid March.