Another Week, Another Rainstorm

The final day of the Victoria Day long weekend will see rain over much of southern Manitoba. It seems that early-week rain is becoming a new tradition of sorts.

A low pressure system will bring rain to much of southern Manitoba on Victoria Day
A low pressure system will bring rain to much of southern Manitoba on Victoria Day

Monday

Monday
16°C / 9°C
Periods of rain.

A low pressure system moving out of the northern United States will bring moderate rain to most of southern Manitoba today. Accumulations of 5-15mm are expected in Winnipeg and the Red River Valley. Areas further west, in south-western Manitoba, can expected accumulations of 15-25mm. There’s a slight chance of a thunderstorm in areas near the international border, but they should amount to little more than a rumble or two and slightly heavier rainfall.

Tuesday

Tuesday
13°C / 10°C
Showers.

The low pressure system from Monday will remained stalled out over southern Manitoba on Tuesday. That means we’ll see showers continue through the day on Tuesday, but actual rainfall accumulations will generally be light.

Total rainfall expected from Sunday evening to the time everything tapers off on Tuesday evening.
Total rainfall expected from Sunday evening to the time everything tapers off on Tuesday evening.

Wednesday

Wednesday
16°C / 4°C
Mainly sunny.

The weather will finally begin to relent on Wednesday, as skies clear and temperatures climb into the mid or upper teens. There will be a breezy north wind on Wednesday, but it will be a nice day overall. Wednesday’s return to reasonable weather signals a major pattern change that is expected to bring much warmer conditions by the weekend.

Long Range

The long range forecast is finally looking hot for a change. Medium-range weather models suggest we could reach the upper twenties, or near thirty degrees by the weekend. There’s still some uncertainty in terms of how hot it will get, but it definitely looks like some above normal weather is finally on the way!

Moderating Trend Gives Way to Rainy Holiday

Temperatures will moderate to seasonal values by the end of the weekend, but the Victoria Day holiday may end up being quite wet.

Relief is in store for Southern Manitobans weary of the prolonged cold weather as milder air is finally set to return to the region. The intense upper-level cold trough over Ontario that has been bringing a strong northerly flow and cool weather to the region will finally begin to collapse, allowing milder air to work its way eastwards again. Temperatures will remain fairly mild while the weather takes a turn for the worse on Victoria Day as a low pressure system brings the potential for substantial rains across much of Southern Manitoba.

Friday
14°C / 0°C
Mainly sunny.

Saturday
18°C / 6°C
A few clouds.

Sunday
18°C / 8°C
Mixed skies.

Today and tomorrow will see daytime highs climbing towards the high teens with minimal in the way of cloud cover. Both days will also see light winds thanks to a ridge of high pressure situated over the province. We’ll likely see temperatures dip to the freezing mark tonight[1], but milder air will be in place for Saturday night making the overnight low around 5°C warmer.

Sunday will be a more unsettled day. Most places in Southern Manitoba will see cloudy periods with a very marginal chance of a shower. Winds will shift out of the south to 20-30km/h as a warm front lifts northwards through the day. Temperatures should climb to around 18°C and the temperature will drop to around 8°C on Sunday night.

Potentially Stormy Victoria Day Holiday

Monday
15°C / 10°C
Mainly cloudy; rain likely.

A powerful low pressure complex will develop over Saskatchewan on Monday which will bring wet weather to Southern Manitoba as a conveyor belt of warm, moist air sets up all the way from the Gulf of Mexico. We won’t see that warm, humid air at the surface, but thanks to a strong southerly flow aloft, strong isentropic ascent over the warm front will produce a very saturated, potentially unstable atmosphere over Southern Manitoba.

Rainfall forecast (in inches) from NOAA's WPC for Sunday evening through Tuesday evening. The WPC is forecasting as much as 25-30mm of rainfall for Southern Manitoba.
Rainfall forecast (in inches) from NOAA’s WPC for Sunday evening through Tuesday evening. The WPC is forecasting as much as 25-30mm of rainfall for Southern Manitoba.

What does this mean? We could see fairly heavy rainfall on Monday. There is still enough time for things to change substantially between now and then, but amounts anywhere from 5-25mm seem quite possible. The rainfall does seem quite convectively driven, and with a moderately strong 850mb jet there’s always the possibility the rainfall becomes attached to the left-exit region and ends up remaining to our south/southeast. We’ll be tracking this system through the weekend and have updates below when things begin to take shape.


  1. Hopefully for the last time until the fall.  ↩

Mother Nature Mixes Up Months

Things will seem decidely early-April as extremely cool air settles in over the eastern Prairies bringing another stretch of days with temperatures some 10-15°C below normal. Seasonal weather doesn’t look to return until the end of the week when the cold air finally begins being shunted off to the east.

Wednesday
7°C / -4°C
Mainly cloudy. Clearing in the evening.

Thursday
10°C / -1°C
A few clouds.

Friday
12°C / 3°C
Mainly sunny. Cloudy periods overnight.

We’ll see a mainly cloudy sky today as we remain stuck under cloud wrapping around the backside of the low pressure system that impacted Winnipeg and the Red River Valley over the weekend and the first half of the week. Accompanying the cloud cover will be extremely cool temperatures for mid-May; the daytime high today will only reach 6 or 7°C, 10-15°C below the seasonal high of 19°C. The cloud cover looks to begin clearing out ovenright as we drop down to a low of -4°C, again nearly 10°C below our seasonal low temperature for this time of year. No precipitation is expected today or tonight.

Tomorrow will bring a few clouds as we sit on the fringe of the organized cloud pushing off to our east and then see some afternoon cumulus clouds develop. Temperatures will moderate a little to around 10°C, however that’s still nearly 10°C below normal for this time of year. We’ll drop to a low of around -1°C overnight under clear skies.

Friday will bring plenty of sunshine with just a few clouds through the afternoon hours. We’ll see a high temperature of around 12°C as milder air continues to slowly push eastwards. There will be a few cloudy periods overnight as a weak disturbance moves thorugh and we’ll see an overnight low near 3°C. Precipitation is unlikely with this disturbance.

Returning to Near-Normal on the Weekend

Things will get back into form by the end of the weekend as the cold trough finally collapses and pushes well off to the east, allowing milder air to spill across the Prairies. Saturday looks like it will have a high somewhere in the mid-teens followed by temperatures near 20°C on Sunday. The weekend looks to be a bit of a mixed bag with sunny skies and relatively light winds on Saturday, but more cloud and stronger winds developing on Sunday as a warm front pushes into the region ahead of a low approaching from Wyoming. Areas all across Southern Manitoba may end up wtih the threat of some showers or rain activity by Sunday aftenroon. We’ll have more details on this system in Friday’s blog post.

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.