A showery and unsettled end to the week will mark the final day with precipitation before a stretch of drier weather builds into the Red River Valley for the weekend and into the first half of next week.

Today will be a rather unsettled day for Southern Manitoba as an upper-level low tracks into southwestern corner of the province. This morning starts out with the remnants of overnight convection tapering off over the Red River Valley, then attention will shift westwards as further thunderstorm development focuses along a trough extending from northeastern North Dakota back towards southeastern Saskatchewan.

In general, scattered non-severe thunderstorms are possible throughout western and south-central Manitoba today. MLCAPE values of 400-800 J/kg will be enough to help some thunderstorm development occur, but weak shear and unfavourable moisture profiles will limit their strength. The main area of note runs from Yorkton, SK into southwestern Manitoba then southward into North Dakota, indicated by the hatched area on the map. In this area, a surface trough combined with better daytime heating and the approach of the upper-level low will introduce the possibility of some non-supercell funnel clouds as thunderstorms develop midday into the afternoon. These can often be eye-catching, but generally pose little threat and are short-lived. That said, if a non-supercell funnel cloud touches the ground, it is considered a tornado, although they too are also typically weak and short-lived.

In Winnipeg, the best chance for shower or thundershower activity will be this morning as any remnants move into the Red River Valley. The remainder of the day will be cloudy with a slight chance of some showers or thundershowers re-developing in the afternoon. Expect a high near 20°C with winds out of the southeast at 15-25km/h. Skies will clear this evening as temperatures drop to around 12°C.

Dry & Mild Weekend

The weekend, on the other hand, will be comparatively pleasant in Winnipeg & the Red River Valley. Skies will be partly cloudy to mixed on Saturday and mainly sunny on Sunday. Daytime highs both days will be in the low 20’s with overnight lows in the low teens. Winds will be fairly light out of the northwest on Saturday at 10-20km/h, but Sunday will be winder with northwest winds to 30-40km/h.

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

Forecast Update – Unsettled Weather Continues for Saturday

A bit of an update is required for today’s forecast as this weather system has evolved in a slightly different way than was expected when originally written on Thursday night.

The overall pattern has progressed to the east more slowly than originally thought, largely in part due to the stalling of an upper low in northern Minnesota. As a result, cloudier skies have remained in the Red River Valley, and some precipitation that was expected to be to our east today has not yet past.

For Winnipeg, well see a few light showers through the morning hours as a weak area of lift moves through from the Interlake. The extent of the showers will be fairly limited and largely confined to the northern half of the Red River Valley. These will taper off by mid-day, but be replaced by a chance for the development of afternoon showers with a slight risk of a thundershower as a trough moves through the region. This trough was fairly active yesterday, but will be far more benign today as less upper-level support is in place. The best chance for showers this afternoon will be over southeastern Manitoba through the Whiteshell and down towards Sprague.

Once we start clearing out for the afternoon, we should still be able to reach our high near 21°C-22°C with light winds.