Summer Arrives in Southern Manitoba

The heat is on the way to Southern Manitoba as warmer air finally spills eastwards bringing positively summer-like weather to the area.

There is astonishingly little to say about the coming few days. Temperatures will climb into the mid–20’s Friday, Saturday and Sunday with overnight lows near 11 or 12°C all 3 days. Winds will be fairly light with the slight possibility of some breezier conditions on Saturday afternoon, but even there it would only likely be 20–30km/h. No precipitation is expected, although there will be a slight chance of some showers on Saturday north of Winnipeg along a very weak cold front from Dauphin eastwards across the Interlake.

All in all it will be a perfect weekend to get outside either here in the city or head up to the cottage for a truncated mulligan of the May long weekend!

Uncertain Start to Next Week

The beginning of next week presents another interesting forecast challenge as yet another Colorado Low forms and pushes northwards into the Dakotas. Model forecasts currently diverge quite a bit, demonstrated easily by the current forecasted storm-total precipitation for Winnipeg produced by each one:

Forecast Storm-Total Precipitation for Monday’s Colorado Low
Model Storm-Total Rainfall (mm)
GDPS 16
NAEFS 8
GFS 0

In general, amounts increase to the south and east of Winnipeg in all the forecast scenarios. Why the big difference? The track of the Colorado Low will depend significantly on how it interacts with thunderstorm activity that develops through the Central Plains as it ejects northeastwards from Colorado. If the convection forms close to the upper-level low and has a significant amount of moisture wrap into it, it will strengthen more, tilting the entire upper-level trough and pulling the system further northwest. If the moisture from the convection pulls off to the east over the upper-level ridge, then the system will be a bit faster, weaker and further southeast.

At this point, there’s still far too much disagreement in the models to make much of a forecast. Overall, the GDPS – currently forecasting the highest amounts for Winnipeg & the RRV – tends to produce too much convection and over-develop lows. They’ve made significant improvements in the latest version of the GDPS, but it still tends to have that strong bias which results in slower systems further to the NW. I think the GFS solution of nothing at all to likely be missing the mark and not quite worth banking on.

That leaves us with the middle-of-the-road answer. Likely some rain on Monday, however not likely as much as advertised by some weather sources right now. We’ll certainly keep an eye on things as they develop and have some updates later in the weekend on how it looks like things are developing.

But for now, get out there and enjoy the hot & dry weather!

A Graceful Return to Form

A quiet week is ahead weather-wise as an upper-level ridge over the region dominates the weather for the remainder of the week. No precipitation is anticipated for the rest of the work week while temperatures slowly climb to above-normal values.

Wednesday
19°C / 4°C
Sunny

Thursday
20°C / 9°C
Sunny

Friday
24°C / 12°C
Partly cloudy

The next few days will be mainly sunny with just a few more clouds working in on Friday. No rain is expected. Daytime highs will start near 19°C today and climb to 24°C by Friday. Overnight lows will remain chilly tonight with lows just near 4°C, but then push towards above-normal of 9–12°C.

Long-Range Outlook

Overall, the weekend is looking quite nice. Temperatures will be in the low-to-mid 20’s with overnight lows in the upper single digits. Some showers or thunderstorms will be possible along a weak cold front draped across the province – likely north of Winnipeg through the Interlake – but at this point anywhere along or south of the Trans-Canada Highway looks fairly dry.

Heading into the start of next week, though, some models are hinting at the possibility of another – albeit weaker – Colorado Low impacting southern Manitoba. The GDPS[1] is forecasting a very rainy Monday with elevated convecting drenching Southern Manitoba with over an inch of rain. The NAEFS[2] takes a more middle ground approach and pushes a weaker system a bit further east, with our region being grazed and getting something in the 5–10mm range. The GFS[3] produces the weakest solution with an even weaker low pushed even further east with little-to-no impact on Southern Manitoba.

It’s too early to say too much about that system other than we’ll be sure to keep an eye on it as we head into the weekend. There are numerous factors which make it look not nearly as bad as the storm we had over the long weekend, so even though it may be the 3rd Colorado Low in 2 weeks, it may not be a significant issue for the region.


  1. Global Deterministic Prediction System – The Canadian long-range forecast model.  ↩
  2. North American Ensemble Forecast System  ↩
  3. Global Forecast System – The United States long-term forecast model.  ↩

Seasonal Weather Returns

We’ll see seasonal weather return this week after a chilly weekend. Temperatures will climb into the mid to upper teens by midweek.

Monday will remain cool as we stay in a northerly flow behind a departing low pressure system
Monday will remain cool as we stay in a northerly flow behind a departing low pressure system

Monday

Today will remain below-seasonal, but temperatures will warm somewhat over the weekend’s values. High temperatures should climb into the mid teens in the Winnipeg and Brandon areas. However, areas closer to the US border will remain under thicker cloud cover and will struggle to reach double-digits. The wind will be brisk at 30 km/h from the north.

Tuesday

Tuesday will be a nice day, as temperatures climb into the mid/upper teens under mainly sunny skies. Winds will be light as high pressure settles in over the region.

Wednesday

Wednesday will be similar to Tuesday, but there will likely be a bit more cloud cover as a system passes to our south. Temperatures will be in the upper teens under a mix of sun and cloud and light winds.

Long Range

It appears that temperatures will continue to warm through the end of the week. However, long range models hint at another weather system passing to our south next weekend, which may once again draw down some cooler air from the north. In general, models suggest that our weather will hover near normal values for the next couple weeks.

Pleasant Weather Returns

Winnipeg will see a reprieve from the below-normal temperatures this weekend as the ridge of high pressure that’s brought the cooler weather shuffles off to the . In its place, a southerly flow will return warmer air to the region with temperatures climbing back to near the seasonal mark.

Over the next few days, no significant weather is expected in Winnipeg or the Red River Valley. Today will start off with some lingering cloud that will clear out through the day. Temperatures will climb to a high of around 13°C with a light southeasterly wind. Expect a low near 0°C under clear skies tonight.

Saturday will bring mainly sunny skies, light southeasterly winds and a high near 16°C. Saturday night will see a low near +2°C with a bit of cloud cover.

RDPS forecast Temperature for Friday Afternoon
The RPDS weather model is forecasting highs climbing above 15°C in Winnipeg on Saturday afternoon.

Sunday’s high will also be near 16°C, however with a few more clouds than Saturday. The temperature will drop to 7°C or so on Sunday night with increasing cloudiness overnight.