The first half of this week will bring generally pleasant summer weather to Winnipeg & the Red River Valley. Some showers or thunderstorms may be possible on Monday and/or Tuesday, but mainly south and east of Winnipeg.
Monday
Today will be a beautiful day for the first 2015 FIFA Women’s World Cup game played here in Winnipeg. Skies will be mainly sunny and high temperatures will climb into the upper twenties. Winds will be relatively light from the north-west at 20 km/h or lower. There may be a few passing showers or very weak thunderstorms south and east of Winnipeg, but nothing of particular significance. Overall it will be a very nice day!
Tuesday
Tuesday will see mainly sunny skies prevail once again, with temperatures in the mid twenties over much of southern Manitoba. Winds will be fairly gusty from the north-west at 30km/h gusting up to 50km/h. Similar to Monday, there will be a risk of thunderstorms south and east of Winnipeg. The risk for storms may shift in later forecasts, but presently it appears that eastern Manitoba could see some marginally severe storms, with perhaps some severe hail. We will provide another update if this threat is expected to materialize.
Wednesday
Benign weather looks to return for Wednesday with mainly sunny skies and no precipitation expected. Temperatures will be in the low twenties and winds will be from the north-west at 20-30km/h.
Long Range
Long range models suggest that generally normal to above-normal weather is expected for the next week or two. Frequent passing weather system will bring unsettled conditions from time to time, with a risk of thunderstorms (generally non-severe). We are certainly not in a full-blown summer pattern just yet, but average temperatures continue to warm!
The weather will take a turn back towards being unsettled this weekend as a weak trough moving through the region brings another round of shower or thunderstorm activity. For the most part, though, it appears that most of the next few days will be quite pleasant.
Today will be a pleasant early summer day with daytime highs around the 23°C mark throughout the Red River Valley with mixed skies – likely leaning towards the cloudier side. Winds will be relatively light at just 20km/h or so out of the southeast. The RRV will see increasing cloudiness overnight with a low near 14°C and winds out of the southeast at 20–30km/h.
Saturday
Saturday is a day fraught with uncertainty. Similar to earlier this week, a disturbance tracking across the Northern Plains of the U.S. will spread rain and thunderstorm activity across North Dakota, while significant uncertainty exists to how far north into Manitoba the precipitation will extend.
Overall, it will be a cloudier day with highs around the 20°C mark. There are several possible outcomes to consider for the day:
We see a large area of rain move across Southern Manitoba on Saturday morning that produces a wide swath of 1–2” of rainfall. It moves out on Saturday afternoon and we see a slight chance of some evening convection.
The bulk of the rainfall stays in North Dakota with a disorganized area of showers moving across Southern Manitoba through the day on Saturday.
The bulk of the precipitation moves through North Dakota while precipitation focuses along a surface trough over Western Manitoba that gradually works its way into the Red River Valley later in the day.
It’s really difficult to tell which outcome will be the correct one at this point; models struggle terribly with systems that are driven by the energy release of thunderstorms; it’s not uncommon to have successive model runs wildly alter precipitation location by over 100km, such as what happened with the system that brushed Southern Manitoba earlier this week.[1]
Probability of ≥ 0.5″ (13mm) of rain between Friday night and Saturday night.
With all the uncertainty regarding what may happen on Saturday, I’d err towards the current HPC 24hr. rainfall probability outlook. This image shows the probability of receiving more than 0.5 inches (13mm) of rain over the 24-hour period. It shows roughly a 20–30% chance for Friday evening through Saturday evening. This would suggest that the heaviest precipitation stays through the Dakotas while further north we see some shower activity with a slight chance of some thunder mixed in. There’s a decent chance of some thunderstorms along the trough line in Western Manitoba in the afternoon, but much of that activity will likely taper off heading towards the Red River Valley.
At this point, though, I wouldn’t rule out all of the precipitation remaining to the west and south of Winnipeg, leaving us with just a cloudy day. We’ll be tracking this system and providing updates in the comments below as things become a little more clear.
Sunday
Sunday will be a fairly nice day with temperatures climbing back into the mid–20’s under mixed skies. There will be a slight chance for some afternoon pop-up shower activity throughout the Red River Valley, but nothing significant is expected. Overall, it looks to be quite a pleasant end to the weekend.
UPDATE: Convective Outlook for Sunday
A risk of thunderstorms exists across much of Manitoba today, including the Red River Valley. Scattered thunderstorms are expected to develop this afternoon as daytime heating, coupled with ample surface moisture, destabilizes the atmosphere. In general, thunderstorms are expected to be non-severe with no organized severe thunderstorm threat. Isolated, short-lived severe storms may be possible, though, particularly along the trough line extending from the Central Interlake southwards through the Red River Valley to the US border.
Convective Outlook for June 7, 2015
The overall thunderstorm setup doesn’t look too impressive today. MLCAPE values around 1000-1250 J/kg will have only around 15 kt of 0-6 km bulk shear thanks to a unidirectional northwesterly wind profile with low speed shear through the column. Temperatures are fairly mild through the depth of the column, resulting in skinny CAPE profiles. Moisture is sufficient, with dewpoint values in the 15-17°C range through the Red River Valley. It’s possible that some localized backing of the surface winds may occur near the trough, providing a little more inflow structure to the thunderstorms.
In general, a relatively unimpressive day; with limited energy available and weak focusing, once convection starts, everything will be “fighting for scraps” so to say and it’s quite likely that thunderstorm activity will be very pulse-y: a storm will spike up in intensity for 10-20 minutes then weaken as another one pops up.
With the higher moisture, and slightly more favourable directional profiles along the trough, there’s a small chance for isolated, marginally severe thunderstorms. The main feature of today’s storms will be fairly heavy downpours under them, but the unidirectional shear looks like it will successfully push storms along at a decent clip, so no one location should see a storm for too long, unless it roots on the trough line. For any storm that might become severe, the reason would likely be marginally severe hail at around 20mm (a nickel) diameter.
The weather will calm down this evening and we’ll be heading into a gorgeous summer week!
The NAM forecast model went from forecasting ≥ 50mm of rain for Winnipeg to 0.5mm on the next run of the model. ↩
After cooler-than-normal weather set up over Winnipeg & the Red River Valley behind last Thursday’s low pressure system, it looks like more seasonal warmth is poised to return to our region as plenty of sunshine makes a return.
Today will see steady improvement with the gusty northerly winds in place this morning gradually tapering off as the cloud cover moves out of the region. By the afternoon we should see fairly sunny skies with a high near 20°C. Expect mainly clear skies and a low near 8°C.
The RDPS is forecasting high temperatures near 25°C on Thursday across much of Southern Manitoba.
The second half of the work week looks great with both Thursday and Friday seeing highs in the mid 20’s and little in the way of significant wind. Thursday looks mainly sunny while a bit more cloud looks possible on Friday as a low pressure system moves north through Western Manitoba. No rain is expected.
Weekend Outlook
The weekend will bring back the chance for some rain with a system moving through on Saturday. Otherwise, the weather seems fairly nice with temperatures in the mid–20’s.
The first part of this week will see unsettled weather as a strong low pressure system passes to our south. This system will likely result in moderate rainfall and a risk of thunderstorms over southern Manitoba on Tuesday.
Monday
Today looks to be mainly cloudy ahead of an approaching low pressure system. There may be a few passing showers throughout the day, but no major precipitation is expected. High temperatures are expected to reach the low twenties with gusty south winds.
Tuesday
Tuesday looks quite unsettled as we sit north of a fairly strong low pressure system over the Dakotas. A warm front will likely be located over northern North Dakota, allowing for warm and potentially stormy weather just to our south. In southern Manitoba, we will remain stuck in a cool easterly flow north of the warm front. As a result of our position relative to the warm front we likely see moderate rainfall during the day with a chance of embedded thunderstorms.
The simulated RADAR reflectivity from the NAM forecast for Tuesday afternoon shows a large area of rainfall moving over Southern Manitoba.
Should the warm front move further north than expected, our risk of thunderstorms will be higher, but at this time that does not look probable. Total rainfall amounts in southern Manitoba could be in the 15-35 mm range, although it is difficult to predict this sort of system ahead of time. Higher rainfall amounts are certainly possible on a localized basis due to isolated thunderstorm activity.
Wednesday
Wednesday looks cool and cloudy as Tuesday’s system departs. We my see a few showers during the day, but in general not much precipitation is expected. The wind will be from the north at around 30 km/h.
Long Range
The long range forecast suggests we’ll see generally normal to above-normal weather through the middle of June. Numerous weak to moderate weather systems are expected to traverse the region over the next while, meaning our weather will continue to feature unsettled patches, before we return to more favourable conditions.
