Stormy Sunday on the Way

After a beautiful start to the weekend, things are about to change. A Low Pressure system will sweep through Southern Manitoba over the next 24 hours bringing a possibility of more showers and storms to some regions in the southern part of the province. 

Wonderful Overnight Temperatures in Manitoba (Shown on the GFSX 850 MB Temperature Model)

Tonight things will start to cloud over ahead of a warm front where we will see the possibilty of the odd shower or two with a chance for a storm, as they move in from Saskatchewan. Showers mainly can be expected in areas of Southwest Manitoba, towards the parkland's region. Temperatures will also be in and around 15C in many regions although closer to 10C in the interlakes, during the overnight hours.  

However, a Mesoscale convective system is forecast to form in Montana and drift Northeastward into Southeast Saskatchewan and Southwest Manitoba, tonight through through the early morning tomorrow along a cold front. Although, the area of convection and showers will outstrip the cold front & warm front, and move fairly fast through the rest of the southern part of the province through the morning. Things will clear out late in the morning allowing for our temperatures to rise into the mid 20's by mid afternoon, with a moist airmass in place. 

850 MB Dewpoint Forecast at 18 UTC, showing 15C dewpoints in Southern Manitoba at 12 noon.

Thing's will start to change for the worst by late afternoon. We will have Temperatures in the Mid 20's and Dewpoints near 16C, if the Dewpoints can get that high MLCAPES will be in the 1000 J/KG range along with SBCAPES rising towards 1,580 J/KG at 3pm. Deep Shear Around 40 knots will also be available. This will be a perfect brewing environment for Severe Thunderstorms that will likely form along a cold front somewhere West Of Winnipeg. The Storms will move likely contain large hail and damaging winds & isolated tornadoes, as they move along east into Ontario by Evening. So I do expect that Environment Canada may mention a chance for showers or thunderstorms in tomorrow morning's forecast issuance at 5am and likely at 11am. Also keep in mind that they may also issue severe thunderstorm/tornado watches and warnings if needed.


Temperatures on Monday and for the rest of the week will continue to stay above average, despite the passage of that cold front. Models are also trending at a possible ridge by late week, maybe allowing our temperatures to reach the low 30's along with high humidity. I will have a post detailing that situation on Wednesday if things hold True.