Unsettled Weather Continues

The wet & unsettled weather seen over the last week in Winnipeg will continue, albeit in a more disorganized fashion, as the series of disturbances that have brought anywhere from 30-70mm of rain to the Red River Valley this week begin moving out of the region only to be quickly replaced.

Today will continue the soggy trend with another round of showers developing through the Red River Valley. Temperatures will be slightly cooler than normal with a daytime high near 19°C. Skies will be mostly cloudy, however there is a chance of seeing the odd sunny break through the day. Winds will be out of the north at around 10-20 km/h through the day. Skies will remain fairly cloudy tonight with a low near 12°C.

RDPS 12hr QPF Amounts valid 00Z Saturday May 28, 2016
One model’s forecast of precipitation totals over Southern Manitoba on Friday

Saturday will bring mixed to cloudy skies to the Red River Valley with a high temperature near 20°C. A few light showers are possible, particularly through the morning hours as a disturbance passes through the Whiteshell, bringing rain through the southeastern portion of the province. Winds will be relatively light through the day. Expect a low on Saturday night near 12°C with some clearing working into the Red River Valley.

Sunday will be the warmest day of the next 3 with a high near 22°C. We'll likely see a fair amount of sun through the morning and midday, but by the late afternoon a trough pushing across the province from the west will bring another chance for showers to Winnipeg & the Red River Valley. Winds will once again be fairly light. Temperatures will dip to around 13°C for a low on Sunday night under partly cloudy skies.

Long Range

The start of next week brings another chance for significant widespread rain for Southern Manitoba as a strong low pressure system develops in Alberta and then pushes eastwards across the Prairies.

GDPS 12hr. QPF Amounts valid 06Z Wednesday June 1, 2016
The GDPS produces a faster system that impacts Southern Manitoba on Tuesady

There's some inconsistency on the timing of this feature. The GDPS is fairly progressive with it and pushes it across the region on Tuesday with another moderate rainfall associated with it. The GFS, however, is much slower.

GFS 12hr. QPF Amounts valid 06Z Wednesday June 1, 2016
The GFS produces a slower system that remains over SK & southwestern MB on Tuesday

The GFS is much slower and holds this system back in Saskatchewan and southwestern Manitoba through Tuesday, and then shifts it in such a way that little rain actually falls over the Red River Valley.

Most long-range models all see this system developing, but with the disagreement in its development & progression, it means at this point we can just say that there's a chance for rain early next week, but we'll have to wait and see.

Winnipeg’s seasonal daytime high is currently 21°C while the seasonal overnight low is 7°C.

Winnipeg’s Weather Takes A Wet & Unsettled Turn

A series of disturbances are set to track into Southern Manitoba through the remainder of the week, brining numerous chances for showers & thunderstorms to the region over the coming days.

Today will start with some sunshine for Winnipeg, but as the day progresses skies will become increasingly cloudy as a disturbance pushes northwards out of North Dakota. Before the sun is hidden away behind the cloud, Winnipeg will reach a warm daytime high near 24°C. By mid-afternoon, showers and/or thunderstorms will be pushing northwards through the Red River Valley, likely reaching Winnipeg for the evening rush hour.

Forecast 500mb Vorticity form the GDPS valid Thursday morning
A complex series of upper disturbances will move through Southern Manitoba through the remainder of the week.

The rainy weather will continue overnight and into Thursday, gradually tapering off by Thursday evening. Expect a low near 14°C tonight, a high near 18°C on Thursday, and a low near 12°C on Thursday night.

The sun should make an appearance again on Friday, returning daytime highs back to the mid-20's. There will be a chance for some showers or an isolated thundershower on Friday afternoon. A weak disturbance moving into the region on Friday night will once again bring the chance for more rain on Friday night.

By the time all is said and done, a fair amount of rain is possible over the coming days throughout the Red River Valley. In general, it's likely that most places will see somewhere between 10-30 mm of rain over the coming 3 days, however with the convective nature of some of the precipitation, it's possible that some areas exceed these amounts and end up closer to the 50 mm mark. Where that may be will depend on exactly how this system sets up, so we'll keep an eye on it and provide updates in the comments below.

Long Range

The unsettled weather will continue into the weekend as a couple more disturbances move through the region. Both Saturday and Sunday show a chance of precipitation for the Red River Valley. Daytime highs will be in the low-to-mid 20's once again.

Winnipeg’s seasonal daytime high is currently 21°C while the seasonal overnight low is 7°C.

Holiday Weekend Turns Unsettled

Summer warmth will continue in Winnipeg for the weekend as southerly winds continue to pull moisture northwards from the United States. By the latter half of the weekend, conditions will become noticeably more humid as a low pressure system begins moving into the region, bringing with it the first organized thunderstorm threat of 2016.

Today will be a beautiful day for Winnipeg & the Red River Valley with mainly sunny skies over the region as temperatures climb to a high near 26°C. Winds will be out of the south at around 20 km/h. There could be an isolated pop-up shower this afternoon through the RRV, but the chance for that will be quite small and not nearly as much shower activity is expected as was seen yesterday through the Red River Valley. Temperatures will fall to a low near 14°C tonight under clear skies.

RDPS Forecast Surface Temperature valid 00Z Sunday May 22, 2016
It will be another warm day on Saturday with high temperatures in the upper-20’s over Southern Manitoba.

Saturday will be another beautiful day with a high temperature once again near 26 or 27°C under sunny skies. It will be a little breezier than Friday with winds strengthening to around 30 km/h. Expect a low near 16°C on Saturday night with winds out of the south near 20 km/h.

Things will begin to change on Sunday as a low pressure system approaches from the west and some of the more humid air from the US begins working into Manitoba. The day will start off sunny with winds out of the south strengthening to 30-40 km/h. It will begin to feel more humid as the day progresses as dewpoint temperatures climb into the mid-teens. It will be warm, too, with a daytime high near 28°C.

NAM SBCAPE, SFC/850/500 X-Over valid 00Z Monday May 23, 2016
Forecast instability (SBCAPE) and wind crossover on Sunday evening.

Through the afternoon, the threat for thunderstorms will develop across southwestern Manitoba and spread eastwards into the Red River Valley for the evening. Instability will peak over SW Manitoba in the afternoon with SBCAPE1 values approaching 2500 J/kg and then tapering off to the 1500-2000 J/kg range as the axis of instability moves into the Red River Valley. Fairly unidirectional wind profiles combined with 30-40 kt of surface to 500mb bulk shear will favour the development of a line of thunderstorms moving northeastwards. The thunderstorms will likely be moderate-to-strong but at this point the threat for severe thunderstorms seems relatively low in the Red River Valley. West of the Red River Valley there is a slight chance for severe thunderstorms, particularly early on in the event before the thunderstorms develop into a line. The primary threat over southwestern Manitoba with any severe thunderstorms that may form will be large hail. We'll continue to keep an eye on things as they develop and refine the storm forecast if needed.

Unsettled Start to Next Week

Holiday Monday will be lead off an unsettled start to next week. Daytime highs will fall back to the low 20's with showers or thundershowers likely to start off Monday and then general unsettledness continuing through the first few days of next week. Conditions will improve through the second half of the week with warmer temperatures returning to the region.

Winnipeg’s seasonal daytime high is currently 21°C while the seasonal overnight low is 6°C.

  1. Surface-based convective available potential energy

A Stretch of Beautiful Summer Weather

Winnipeg will see plenty of sun and warmth as the first deep southerly flow of the year develops this week, advecting warm and increasingly humid air northwards from the Great Plains of the United States into Manitoba.

The coming days will be bring beautiful summer weather with plenty of sunshine and temperatures soaring into the mid-20's. This afternoon will also bring breezy southerly winds to around 30-40km/h. We'll see just a few clouds today as a weak disturbance moving into Manitoba from the western Prairies slowly falls apart.

RDPS Temperature Forecast valid Thursday Afternoon
The RDPS shows warm summer-like temepratures across the Prairies on Thursday.

Thursday and Friday will both be sunnier days with winds out of the south at 20-30km/h. Thursday will be the windier of the two with gusts in the 40-50km/h range possible, while Friday will see winds more steady and a bit lighter. For both days, the high will be near 26 or 27°C.

Nights will be much milder than we've seen lately with overnight lows in the 12-15°C range.

Of note, and a significant change from what we've seen so far this year, is that this prolonged period of southerly winds will finally bring some more humid air into the region as moisture from the Great Plains of the United States. By the end of Friday, dewpoints will have climbed from near 0°C into the upper single digits. While we won't notice a significant difference in how it feels, it will certainly alleviate some of the moisture stress for plants which could help improve the fire danger in the region.

Long Range: 2016's First Humid Days?

For the weekend, the weather will continue distinctly summery with high temperatures climbing into the upper 20's. Along with the continued warmth, those southerly winds will continue to push moisture northwards and begin pushing dewpoint values towards something that may actually begin to feel humid. By the end of Saturday, it is forecast that the dewpoint will climb to around 12-13°C which is a fairly typical summer value for the region. On Sunday, however, a surge of humidity is expected to push into Manitoba, bringing dewpoint values into the 15-17°C range, which will begin to feel a bit humid when combined with a high near 29°C.

GFS Surface Dewpoint Forecast valid Sunday Evening
The GFS shows clearly this weekend’s stream of humidity from the Gulf of Mexico northwards through the Great Plains into Southern Manitoba.

With the humidity will also come unsettled weather. It's far to early to get into many specifics, but beginning on Sunday afternoon, the chance for thunderstorms will make an appearance across Southern Manitoba. Early indications are that there may be a slight chance for severe thunderstorms with a primary threat of severe hail. We'll be sure to keep an eye on things as they develop and provide a more in-depth outlook in our Friday post.

Winnipeg’s seasonal daytime high is currently 20°C while the seasonal overnight low is 6°C.