Nasty Week Ahead

After a nice weekend, we’re in for a nasty work-week. More rain and chilly temperatures are on the way.

Rain is expected in south-eastern Manitoba on Monday
Rain is expected in south-eastern Manitoba on Monday

Monday

Monday
9°C / 5°C
Rain

Today will see rainy weather return, or continue, in southern Manitoba, depending on where you live. Western sections of the province should remain mostly dry, but south-eastern sections will be getting wet, as another strong weather system moves up from the south. Rainfall accumulations of 10-20mm are expected in Winnipeg with 15-25mm in areas south-east of the city, including Steinbach. Locally higher amounts are possible in the south-east corner of Manitoba where heavier rain bands will likely develop. The rain will be accompanied by a strong northerly wind, just adding to the misery!

Tuesday

Tuesday
9°C / -1°C
Mix of Sun and Cloud. Chance of Showers.

There may be some lingering rain showers on Tuesday morning in south-eastern Manitoba, and some more pop-up showers in the afternoon, but generally speaking Tuesday will be a dry day. It will also be a fairly crummy day, with a cool airmass of Arctic origins surging southward into the province. High temperatures aren’t likely to crack the double digits in most areas.

Wednesday

Wednesday
8°C / -2°C
Mix of Sun and Cloud. Chance of Showers.

Wednesday will see a continuation of Tuesday’s nasty, cool conditions, with even colder Arctic air surging southward. Once again, temperatures are not expected to reach double-digits, except for maybe far western sections of southern Manitoba. Pop-up showers may develop in the afternoon, just to cap things off!

Long Range

We should see temperatures return to near normal values by the end of the week into the weekend, however no above-normal weather is in store for the foreseeable future.

A Short Warm-Up

There will be only a couple days of sun before the threat for rain returns to the Red River Valley.

After a few unsettled days across Southern Manitoba which, depending on where you were, brought anywhere from no rain to upwards of 15-25mm, the weather is set to offer refuge from the gloom in the form of sunshine and perhaps the warmest temperatures we’ve seen all year. Unfortunately, the pleasantries will be cut short when another complicated weather set-up involving a large cut-off upper low and multiple impulses travelling northeastwards out of the United States redevelops.

Friday

Friday
15°C / 5°C
Mainly sunny.

Today will be a pleasant day with mainly sunny skies and winds out of the northwest at around 20km/h. The temperature should reach a high around 15 or 16°C, which will likely be the warmest day in Winnipeg since we hit 15.1°C on April 23rd. Unfortunately, this will still be 2-3°C below our seasonal normal.

The normal average temperature and departure from it over the last 90 days in Winnipeg.
The normal average temperature and departure from it over the last 90 days in Winnipeg.

Despite the temperatures warming up slowly, the fact that we’ve spent such an unbelievable amount of time with temperatures below normal is what is driving many in Winnipeg to dream of warmer climes. Even last year, which had the latest snowpack melt on record[1] had already seen temperatures as high as 26°C by this point.

Unfortunately, I don’t have much good news in that department.

Saturday

Saturday
18°C / 7°C
Increasing cloudiness late in the day.

Saturday will be the nicest day of the year so far, hands down. Skies will be mostly sunny until the cloud shield associated with the next low pressure system begins creeping into the region in afternoon or evening. Winds will be out of the south at around 20-30km/h and the temperature will skyrocket to take the top spot of 2014 so far…at a seasonal 18-19°C![2].

Saturday night will be mainly cloudy with a chance for showers pushing into the southern Red River Valley overnight. The temperature will drop to around 7°C.

Sunday

Sunday
12°C / 3°C
Cloudy. Periods of rain likely.

Sunday will bring a return to cooler, wetter weather as the weather pattern shifts back into a more unsettled regime. It’s a bit early to get too specific, but it seems likely that some light rain is likely as a low pressure system meanders into the Red River Vally from southwestern Manitoba. The high will be close to 12°C and the low will dip down to 2-3°C.


  1. In 2013, the snow pack did not reach a trace amount until April 27th in Winnipeg.  ↩
  2. Crack the champagne!  ↩

Wet Week Leads to Gradual Improvement

A couple more days of unsettled weather will give way to some of the warmest temperatures of the year.

The main weather story will be gradual improvement as the week progresses. Currently we’re under the influence of a broad trough of low pressure that has brought scattered showers to the Red River Valley over the past couple days.

A complicated, high-amplitude flow is developing over the eastern Prairies.
A complicated, high-amplitude flow is developing over the eastern Prairies.

Multiple bands of precipitation will be in place over Southern Manitoba today thanks to multiple disturbances and a fair amount of instability. As the upper-level flow finally organizes itself, a Colorado Low eject northeastwards on Thursday bringing potentially significant rainfall to the Red River Valley and Southeastern Manitoba. The unsettled weather will linger through Thursday night but then a weak ridge of high pressure will begin building in from the west, bringing more settled weather with relatively warm temperatures, especially compared to what we’ve been suffering through so far this spring.

Wednesday
12°C / 6°C
Mainly cloudy. Occasional showers likely.

Thursday
12°C / 4°C
Showers, possibly heavy at times. 5-15mm.

Friday
15°C / 5°C
Clearing.

Today

Today will bring mainly cloudy skies to the Red River Valley as a large low pressure complex stretching from Northern Saskatchewan to Colorado slowly begins organizing itself. More organized showers will fall through much of the day west of the Red River Valley through southwest regions and the Parkland with total accumulations around 5-10mm, but here in the valley we will likely only see scraps of elevated convective showers occasionally moving over the area.

I say likely since there is pretty high uncertainty in exactly how this system will evolve today. The band of showers to our west will slowly creep eastwards towards the RRV through the day and likely push into the western Red River Valley this afternoon. There’s a chance that it will continue pushing eastwards, and if that’s the case then we might see some more organized precipitation later in the afternoon into the evening. There’s also a very outside chance that this whole thing bumps eastwards mid-morning and we’re the ones stuck under the showers for the day.

Complicating matters will be a secondary band of precipitation that will develop this afternoon and lift northwards out of North Dakota and Minnesota. It’s currently forecast to just clip SE Manitoba, but if the upper level trough tilts a bit more, which it has been doing more than the models have been forecasting for 2 days now, that band of rain could end up inside the Red River Valley.

As a third complicating factor, there seems to be fairly unstable mid-levels over most of Southern Manitoba, so even if the precipitation stays to our west and east, there will still be a chance for some light showers zipping across the valley.

Total precipitation by Thursday evening from the RDPS. The question is will it even be close to right?
Total precipitation by Thursday evening from the RDPS. The question is will it even be close to right?

It’s a very complicated setup; most models agree that there will be rain on the western and eastern fringes of the Red River Valley with little in between[1], however slight variations in the actual positions of systems could change things quite dramatically. For that reason I’m say that there’s a good chance we’ll see occasional showers today. We may see more, we may see less, but this is a situation where trying to be any more specific than that will likely be a futile effort.

What is a little more certain is that we’ll see a high near 12°C today with light southeasterly winds.

The threat for showers will continue through the overnight period through most of the Red River Valley. We’ll drop to a low around 5 or 6°C with winds shifting around to the north.

Thursday

Thursday looks to be the most active day. A strong Colorado Low will track into Minnesota, spreading rain ahead of it into Southern Manitoba. Moderate instability aloft coupled with strong lift and enhanced convergence thanks to the deformation zone will result in showers, potentially fairly heavy at times, through much of Southern Manitoba. There may even be a very slight chance of a rumble of thunder or two.

The wet weather will likely last through much of the overnight period as well. By the end, anywhere from 5-15mm of rain seems likely over the Red River Valley; amounts will likely vary over short distances, and it’s impossible to say where will see the most rain until we’re closer to the event. I’d really love to be more specific, but with this rapidly developing, complex system, the models can be quite misleading and the best forecast will come from observing what’s actually happening and how things are developing in real time.

The high temperature on Thursday will be near 11-12°C once again, and the overnight low near 5°C.

Friday and Beyond

The weather finally looks to turn towards a more pleasant pattern for the end of the week. A cut-off cold low will spin aimlessly over the northwestern Prairies, leaving us on the warmer side of things as slightly milder air manages to work its way into the region. No substantial warm push is on the way, but with the cold air locked up well to our northwest, temperatures should manage to climb to around 15-16°C on Friday, Saturday and Sunday.

It seems quite likely that we’ll see our warmest day of the year this weekend. Currently, the warmest day we’ve had was a mere 15.1°C on April 23rd, but Saturday looks likely to beat that by a degree or so. Overnight lows are expected to sit near 5-6°C through Friday, Saturday and Sunday, which will be right around normal for this time of year.

Skies should be mainly sunny on Friday and Saturday, however we will likely see some cloud and a very slight chance of a shower on Sunday as a weak low pressure system pushes into western Manitoba.


  1. And I’m inclined to believe it given how often any sort of convective precipitation manages to end up on either side of Winnipeg.  ↩

Unsettled Week Ahead

Summer weather will continue to elude us as a complicated weather pattern is set to bring more unsettled weather this week. A series of moderate to strong disturbances will move through Southern Manitoba, each bringing a chance for rain. The first major disturbance looks to move through on Tuesday, with a second major disturbance coming through on Wednesday night.

The forecast surface weather pattern on Monday afternoon
The forecast surface weather pattern on Monday afternoon

At this point it appears that each of these pieces of energy will just bring light to moderate rain to parts of southern Manitoba. However, there is always the potential for heavier amounts if convective elements (i.e. thunderstorms) become embedded within the larger area of rain. These disturbances will be coming in from the south-west along a strong jet stream.

This strong jet may also be the focus for severe thunderstorms in the US Great Plains this week, so you may wish to keep tabs on that if you’re a thunderstorm enthusiast!

Monday

Monday
12°C / 5°C
Mix of Sun and Cloud

Today will be seasonably cool, with high temperatures in the low teens. Skies will be a mixture of sun and cloud to mainly cloudy, but at least no precipitation is expected. There will be a breezy south wind during the day, but it shouldn’t be quite as windy as it was on the weekend.

Tuesday

Tuesday
15°C / 6°C
Mainly Cloudy. Showers.

Tuesday is expected to feature showers in much of southern Manitoba. There is also a slight risk of a thundershower, which may lead to isolated pockets of heavier rain. Temperatures will be in the low to mid teens with a south wind once again.

Wednesday

Wednesday
15°C / 2°C
Mainly Cloudy. Chance of Showers.

Wednesday will be, you guessed it, unsettled once again, with the threat of showers remaining in southern Manitoba. Temperatures will be in the low teens, with a light northerly wind.

Long Range

The long range forecast suggests we’ll see warmer temperatures this weekend. By warmer, we’re talking probably upper teens or maybe low twenties. It won’t be anything spectacular, but those values will feel quite warm considering the weather we’ve seen as of late.