Stormy Forecast

     Uncertainty still exists with the upcoming system which will give us precipitation tonight through to Tuesday night. We really wont know for sure until the thunderstorms begin developping south of the border later this afternoon and evening. Today is definitely a windy day, with winds from the south east at 30 or 40 km/h, and gusts over 50 km/h. Hold on to your hats!

     Here's my current best forecast for tonight and tomorrow:

     I'll be updating my forecast throughout the event, but here's how it looks so far. Some scattered showers are moving through southern Manitoba this afternoon, though it really isn't much. Most of us will likely see nothing until tonight.
     More organised showers and thunderstorms are expected to form south of the border in the Dakotas, Wyoming and Montana this evening. These storms will move northeastward into southeast Saskatchewan, Manitoba and northern Ontario later in the evening and overnight. Rain looks to be heaviest and more widespread in northwest Ontario, over the Interlake, and over southwest Manitoba and southeast Saskatchewan. That being said, the highest risk for thunderstorms will be in south/southeast Manitoba and northwest Ontario. At this point it does not appear storms will be severe on our side of the border, though some bigger storms may give some small hail, gusty winds and torrential downpours. Areas that get storms will see higher rainfall amounts.

Map shows thunderstorm risk overnight tonight.
Light blue = small risk. Dark blue = medium risk
Details on storm potential by following tab at top.

     Generally, 5-10 mm can be expected around Winnipeg tonight with the showers, though higher amounts are possible if we get thunderstorms. At this point, it appears we will see a break in the precipitation in the dry slot tomorrow morning before wrap-around precipation takes over in the afternoon with an additional 5-10 mm possible by Tuesday night. This wrap-around precip. will dump heavy rain in southwest Manitoba and the Interlake where upwards of 30 mm of rain will be possible.     Rain will likely also make a switch over to snow in west and southwest Manitoba tomorrow afternoon and evening, and here in southeast Manitoba by Tuesday evening and overnight. 5-10 cm will be possible in areas north of Brandon, with 10-20 cm possible over higher elevations such as in the Riding and Duck Mountains. Areas around and south of Brandon, and over south-central and southeast Manitoba will likely only see meager snowfall amounts of less than 2 cm.
     All the precip. looks to be all set and done by early Wednesday morning, with a few lingering flurries possible in the morning before beginning to clear in the afternoon.

     Here's a map of predicted precipitation amounts by the GEM model for the whole system (tonight through to Wednesday morning). Please note that these amounts include both rain AND snow. Use the legend on the right for the colour-codes, and click on the image to enlarge:

    

     Thank you for taking the time to read my forecasts =)