Tag: Rain

Summer Heat Brings First Significant Thunderstorm Risk of the Year

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The mercury will soar today thanks to the significant upper-level ridge over the region that has brought very warm air into the province. That hot weather will moderate a bit for the weekend, though, as a low pressure system moving through tonight will bring a threat of thunderstorms to the region and push temperatures down closer to seasonal values.

A scorcher is on the way today as temperatures climb above the 30°C mark across much of southern Manitoba. Southerly winds around 30 km/h will help bring up some humidity from the United States, and by the afternoon it may actually begin to feel muggy as well.

The weather will turn later this afternoon over the southwestern corner of the province as a cold front pushes eastwards across the province. Thunderstorms will develop near the Saskatchewan border mid- to late-afternoon and then grow into a line along the cold front as they progress eastwards through the evening.

Thunderstorms are possible across Southern Manitoba today with a risk of severe thunderstorms over the Parkland, southwestern portions of the province, and the western Red River Valley.

The biggest risk for severe weather will be in the afternoon during the early stages of thunderstorm development. Thunderstorms will have more energy to work with with temperatures in the 30’s combining with dew point values in the mid-teens providing 2000-2500 J/kg of CAPE. Shear will be a bit lacking, at 20-35 kt of 0-500mb bulk shear depending on the position with respect to the cold front.

That said, there’s a slight risk of severe thunderstorms across southwestern Manitoba tomorrow with the primary threat being large hail. Some of these thunderstorms may also produce strong to severe wind gusts.

The energy and dynamics to support these storms will shift as the evening progresses, with the best support slumping into the United States. As the line moves into the Red River Valley, the threat for severe weather diminishes, however thunderstorms will likely continue to roll eastwards through the night.

The expectation for thunderstorms to decrease in severity as they progress eastwards is based on the belief that models are being too aggressive in their advection of elevated dew point values into Southern Manitoba. If higher dew point values pushing into the upper teens do in fact show up in the region, the threat for severe thunderstorms will persist all night, and there would be an increased likelihood of a severe squall line along the cold front. Strong linear forcing could produce bowing segments with severe winds should that outcome occur.

The Weekend

Saturday will bring clearing skies in the morning, and then a few afternoon clouds with a slight chance of another shower or thundershower in the afternoon. The showers will move down from the northwest on the backside of Friday’s low, but as of writing it seems like most guidance suggests the showers will stay to the north and pass through the Interlake. That said, there’s a chance Winnipeg may see a little more rain in the afternoon.

The GFS is an outlier forecasting widespread showers across Southern Manitoba on Saturday afternoon

Aside from that, it will be a pleasant day with a high near 26°C and westerly winds to 20-30 km/h. Temperatures will dip to around 15°C on Saturday night with clearing skies.

Sunday will bring mainly sunny skies and a high temperature near 25°C to Winnipeg. Winds will be 15-25 km/h out of the north. All things considered, a great day!

Winnipeg’s seasonal daytime high is currently 22°C while the seasonal overnight low is 9°C.

One More Damp Day, Then May Ends With Nicer Weather

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Winnipeg will be under the influence of the storm system that has been bringing showers to southern Manitoba the past couple days for one more yet, but then a return to more pleasant weather will quickly return for the end of May!

More showers are on the way for Winnipeg today as moisture continues to stream southwards through the province on the back-side of the storm system that moved through over the weekend. Breezy northwesterly winds of 30 gusting 50 km/h will make today’s high of just 11°C feel rather dreary. The chance for showers will continue tonight, although it won’t be quite as likely, as temperatures drop to a low near 6°C.

More showers are expected across much of Manitoba today and tonight.

Sunshine will return to Winnipeg on Tuesday as skies clear for the afternoon. There will be a slight chance of showers in the morning as one more little disturbance ripples through, but as skies clear midday temperatures will warm up to a high near 18°C. The wind will continue to be gusty out of the northwest, but the sunshine should make for a much more pleasant afternoon. Skies will completely clear out by evening as winds taper off and Winnipeg heads to a low near 8°C.

Wednesday will be a beautiful day to end the month on; sunny skies with a high near 24°C are on the way with light winds of just 10-20 km/h out of the west. The low will be relatively mild on Wednesday night at around 10°C.

Long Range

The remainder of the work week looks pleasant with continued sunny to mixed skies and highs in the low 20’s. A system will approach Manitoba on Friday, but at the moment guidance suggests it will remain to the south and west. There is general agreement that next week may turn more unsettled once again, so we’ll be keeping an eye on that as the week progresses.

Winnipeg’s seasonal daytime high is currently 22°C while the seasonal overnight low is 8°C.

Mixed Bag For Second Half of the Work Week

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Winnipeg will dodge the worst of a major storm system that will slam Alberta and portions of Saskatchewan with strong winds and rain; comparatively, things will be quite pleasant!

A major storm is developing over Alberta today that will bring 30-50 mm of rain to the province alongside winds gusting over 100 km/h. This system will spread eastwards and bring significant weather to Saskatchewan later today, but will begin to weaken as it approaches Manitoba overnight. While Winnipeg will be spared from the brunt of this storm, some breezy and unsettled weather is still on the horizon.

First up, today will be a warm and windy day as moderate southerlies develop ahead of the Alberta storm. We should see fairly sunny skies, but winds will pick up out of the south-southeast to 30-40 km/h with gusts to 60 km/h through the morning and early afternoon. Temperatures will be near-seasonal with a high of 21°C.

The winds will continue out of the south-southeast tonight at around 30 gusting 50 km/h as cloud cover pushes in late overnight. Temperatures will drop to a low near 11°C.

Thursday will bring cloudy skies to the region as a trowal1 moves through the region. Whether or not Winnipeg will see rain is still somewhat uncertain; support for it definitely tapers off as the feature moves into the Red River Valley, but it will likely be able to sustain a band of rain or showers that will move through mid-day. A second batch of showers is possible in the early evening as the low pressure system moves into the Interlake.

More recent model runs are beginning to show accumulating rainfall in the Red River Valley on Thursday

While the winds will be breezy first thing, they should diminish through the morning as the low approaches. Temperatures will reach a high near 18°C. Temperatures should dip to around 12°C on Thursday night with the cloud cover breaking up.

Friday will bring mixed skies to Winnipeg & the Red River valley with a high near 19°C. It should stay dry, with any showers to our east and north. Winds will be out of the west at 15-25 km/h. It looks like skies should be fairly clear on Friday night as temperatures dip to a low near 9°C.

Long Range

The mixed bag continues this weekend with Saturday likely bringing a fair amount of sunshine and highs near the 20°C mark, but things take a turn on Sunday with highs dropping into the mid-teens as showers slump southwards out of northern Manitoba. With breezy northwesterly winds, it will likely be a relatively unpleasant day. The unsettled weather may persist into Monday, but then the remainder of next week looks pleasant with dry conditions and highs in the low 20’s.

Winnipeg’s seasonal daytime high is currently 21°C while the seasonal overnight low is 7°C.

  1. Trowal stands for “trough of warm air aloft” and is the warm air rising around a low pressure system from the occluding frontal wave. ↩

Rain Today Gives Way to Sunny & Seasonal Weather

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The reprieve from yesterday’s 10-20mm of rain that fell across the Red River Valley will be short-lived as another disturbance will move through the region today and bring more wet weather. Fortunately, things will improve quickly with clouds clearing out for Tuesday and Wednesday alongside a rebound to seasonal temperatures.

It will be another cool one in Winnipeg today with mainly cloudy skies and intermittent showers as a disturbance slumps southwards from the Interlake, bringing another couple millimetres of rain to the region. Temperatures will top out at just 12°C today, kept down by the cooler air mass and brisk northerly winds that will develop a bit later this morning to around 30 gusting 50 km/h. The rainy weather will finally taper off late this afternoon into the early evening, and Winnipeg will be left with cloudy skies and northerly winds of 15 to 20 km/h as temperatures dip to a low near 8°C.

Light rainfall accumulations are expected across portions of Southern Manitoba today.

Tuesday will be a much nicer day with skies clearing in the morning and then temperatures climbing to a high near 19°C. Winds will remain out of the north to northeast at 15-20 km/h. Expect a low near 9°C on Tuesday night under clear skies with light winds.

Wednesday will bring more pleasant weather to the city with mainly sunny skies and a high near 21°C. Winds will increase out of the south from calm to around 30 km/h through the day.

Long Range

Conditions will turn more unsettled through the second half of the week as a major storm develops over Alberta and track eastwards.

A very potent low pressure system will develop in Alberta on Wednesday, bringing very strong and potentially damaging winds with it. This system will track eastwards and weaken through the second half of the week.

As it does so, Winnipeg will see a few chances for precipitation Thursday through Saturday, but it really seems like we’ll avoid the worst of this system. We’ll be keeping an eye on it as it develops and begins to push towards the region.

Winnipeg’s seasonal daytime high is currently 21°C while the seasonal overnight low is 7°C.