Threat of Massive Hail is the Driving Force Behind a Widespread Strong Severe Risk in Southeast Manitoba Sunday Afternoon IF Storms Develop

/

NOTE: YOU CAN CLICK ON THE MAP TO OPEN A ZOOMABLE IMAGE

It’s been a very active few days across the Prairies and this morning was no exception, with destructive wind gusts pummelling parts of East Central Saskatchewan and the Westman and Parkland Regions.

Unfortunately, this trend of dangerous severe weather will likely continue this afternoon, but this time the target will be Southeastern Manitoba. The possibility for massive hail across the region has resulted in this being a widespread Strong Risk for severe thunderstorms for this afternoon.

GOOGLE AD (NOT ENDORSED BY INSTANT WEATHER)

Once again, weather models are struggling with pinpointing these storms, but the ingredients for severe weather should all be in place and there is a potential for severe storm development, which warrants a forecast. Today will be an “IF day” in the sense that IF storms end up developing, they are expected to be very strong and widespread across the region. With the intense heat and temperatures feeling into the low 40s, along with ample moisture and instability, the environment will be primed for storms, but a strong enough trigger will be necessary for them to occur.

This storm development could begin early this afternoon, as the existing line of storms pushes northeastward through the Interlake Region. Behind this, additional storms could develop along a cold front and make their way eastward through the Red River Valley and Interlake Region during the afternoon and the Eastman and North Eastman Regions in the evening and overnight hours. Whether or not this development actually occurs is still uncertain.

GOOGLE AD (NOT ENDORSED BY INSTANT WEATHER)

If the severe thunderstorms end up developing this afternoon, the major threat will be very large hail. Golf ball-sized hail appears to be likely with these potential storms, with even up to tennis ball-size possible. Widespread damaging wind gusts over 100km/h would also be associated with these storms, as well as up to 100mm of rain resulting in localized flooding and the possibility of a tornado.

This could very well end up being a bust, but the threats involved in the event that storms do develop are quite significant and it’s important to be prepared.

Greatest Severe Thunderstorm Threat for Saturday Afternoon Shifted West; Still Slight Risk for Southern Manitoba

/

NOTE: YOU CAN CLICK ON THE MAP TO OPEN A ZOOMABLE IMAGE

Following this morning’s thunderstorms, we are still expecting more severe weather for Southern Manitoba later today, however the anticipated strength of those storms has diminished and the area they’re expected to hit has also changed. The strongest storms of the day are now expected in Southern Saskatchewan, but the potential for damaging winds, large hail. and localized flooding still result in a Slight Risk for severe thunderstorms in the Westman, Parkland and Northern Interlake Regions.

GOOGLE AD (NOT ENDORSED BY INSTANT WEATHER)

The exact timing of these storms is tricky to establish due to uncertainty between weather models, leaving three possible scenarios.

Scenario 1

Large storms could begin to develop in the mid-afternoon just east of the Saskatchewan border in the Parkland Region as isolated supercells which would travel northeastward across the province. Development of additional storms would continue through the evening and early overnight, following the same northeastward trajectory. These storms would then be followed by a more organized cluster of storms crossing through the region Sunday morning.

Scenario 2

Smaller storms could start to develop in the Parkland Region in the mid to late afternoon and quickly become more organized into a strong line that spreads into the Northern Interlake and travels southeastward through the evening before starting to fall apart approaching the Central Plains overnight. In this scenario, the storms Sunday morning would be weak, if they occur at all.

Scenario 3

A handful of small storms could pop-up starting in the later in the afternoon, once again in the Parkland Region, and continuing into the late evening, but not amount to anything too concerning. Then, in the early morning hours, a large cluster of storms could push northeastward into the region from Saskatchewan, followed by a second round of strong storms later in the morning.

GOOGLE AD (NOT ENDORSED BY INSTANT WEATHER)

Regardless of which of the three scenarios unfolds, it is likely that there will be strong storms in Manitoba over the next 24 hours. The threats from these storms will be the large hail, with up to toonie-size likely and damaging wind gusts that could exceed 100km/h, as well as one or two tornadoes . There is also the concern of localized flooding because these storms are expected to occur over the same area. It’s important to note that the level of uncertainty between weather models means that this could very well end up being a classic “bust” day, but we believe that it is better to be prepared in the event that any one of these scenarios materializes.

Slight and Strong Risk for Severe Thunderstorms Across Southern Manitoba Saturday, Hitting in Multiple Rounds

/

NOTE: YOU CAN CLICK ON THE MAP TO OPEN A ZOOMABLE IMAGE

It will be a hot day across Southern Manitoba on Saturday, but there will be some active weather, in the form of a line of severe thunderstorms, to contend with before the temperatures start to climb. More storms will hit the region later in the day, but the timing remains a little unclear. Regardless, the risk of large hail and damaging wind gusts, along with the possibility of a tornado makes this a Strong Risk for severe thunderstorms in Southwestern Manitoba, including Brandon, and a Slight Risk across much of the rest of Southern Manitoba.

GOOGLE AD (NOT ENDORSED BY INSTANT WEATHER)

The first line of storms will make their way into Southwestern Manitoba around sunrise Saturday morning, packing a punch with strong winds and large hail. These storms will lose steam as they travel eastward across the width of the province throughout the morning and into the early afternoon. Following this line of storms, it will be a hot day across the region, feeling closer to 40°C with the humidity, which should provide ample fuel for another wave of storms. The exact timing of this second line of storms is still uncertain. Some models are suggesting that the additional storms could start Saturday evening and make their way across Southern Manitoba overnight and into Sunday morning. On the other hand, there are other models that show the second line of storms developing in the early morning hours of Sunday and continuing into the early afternoon, followed by a third line of storms beginning Sunday evening. Due to this uncertainty, we will likely have a revised forecast for the secondary storm development posted Saturday afternoon.

The threats from these storms will be the large hail, with up to golf ball-size possible, as well as widespread damaging wind gusts that could exceed 100km/h and approach 120km/h, along with the possibility of a tornado or two touching down. There will also be a flooding risk, with these storms expected to bring up to 100mm, particularly to areas that will experience multiple rounds of storms.