Tag: Thunderstorms

Showery Weather Ahead

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A persistant Arctic vortex over the Eastern Arctic will continue reinforcing a westerly to northwesterly flow over the Prairies which has been bringing cooler summer weather to Southern Manitoba. Multiple disturbances are forecast to track down in the northwesterly flow which will produce a showery second half to the week.

Wednesday

22°C / 13°C
Increasing cloudiness then showers with a risk of a thunderstorm in the afternoon.
Thursday

21°C / 11°C
Cloudy with scattered showers. Windy.
Friday

22°C / 10°C
Mainly sunny.

We’ll see a fairly cloudy day today as temperatures climb to only around 22°C. A trough of low pressure will work it’s way into and through the Red River Valley bringing scattered showers with the risk of a thunderstorm through much of the day and the early evening. No severe weather is expected. Skies should clear overnight as we drop to a low of around 13°C.

On Thursday a second – more potent – system will begin working it’s way through the province. Clouds will roll in early on Thursday as an upper disturbance tracks an area of rain through the Interlake. Here in the Red River Valley we’ll likely see another round of scattered showers starting midday with the winds picking up out of the north to around 30km/h with gusts to 50 or 60km/h. Thunderstorms aren’t expected and we’ll see a high near 21°C. Things will clear out overnight as we head to a low of about 11°C.

Friday will bring more stable weather with mainly sunny skies and a high of 22°C. Winds will continue to be breezy through the morning but should begin to let up in the afternoon. Things look very pleasant through the weekend with mainly sunny skies and highs in the mid–20’s with overnight lows in the 12–13°C range.

Mixed, Mild Weather Ahead

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A northwesterly flow building over the province will bring mild temperatures and bouts of unsettled weather with little in the way of severe storm threats, making for a fairly pleasant week overall.

Monday

21°C / 12°C
Mostly cloudy; clearing late in the day.
Tuesday

24°C / 13°C
Mainly sunny. Slight chance of showers or thunderstorms in the evening.
Wednesday

24°C / 12°C
Cloudy periods. Chance of showers in the evening.

Today will be marked by relatively cloudy skies with a breezy northwesterly wind as the low pressure system that brought severe thunderstorms to Southern Manitoba yesterday slowly moves out of the province. This has ushered in cooler air once again which will keep our temperatures fairly cool for the next few days – we’re expecting daytime highs to only climb into the low-to-mid 20’s and overnight lows to sit near the 12–13°C mark.

Tuesday will be a pleasant day with mainly sunny skies and a high near 24°C and while there’s a chance of a shower or thunderstorm on Tuesday evening, it really is an outside chance and much more likely to happen over SW Manitoba than over the Red River Valley.

500mb upper trough approaching Manitoba from the Northern Prairies on Wednesday evening (from the GFS).

500mb upper trough approaching Manitoba from the Northern Prairies on Wednesday evening (from the GFS).

On Wednesday we’ll see a chance of showers later in the day under a mixed sky as a long-wave trough rotates towards Southern Manitoba from the Northern Prairies. At this point it doesn’t look too energetic and there’s little in the way of thunderstorms expected. We’ll se a high near 22°C and a low once agin in the 12–13°C range.

Rainy — And Potentially Stormy — Thursday Ahead

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Sunny skies will turn rather unsettled on Thursday as multiple disturbances move across Southern Manitoba.

Wednesday

Wednesday

28°C
Mainly sunny. Chance of showers near the U.S. border.
Wednesday Night

15°C
Increasing cloud. Showers beginning overnight with the risk of a thunderstorm.

We’ll see mainly sunny skies today as we spend a short amount of time in the stable air behind the cold front that passed through yesterday. That front will be sitting south of the border in North Dakota, however a very strong upper-level jet will be in place through Northern North Dakota near the Canadian border. There will be a slight chance of showers near the border thanks to the extra lift supplied by this feature.

We’ll see increasing cloudiness tonight as the upper-level jet starts pushing back northwards and the aforementioned cold front becomes a warm front and start pushing northwards again. Showers – with the risk of a thunderstorm – will develop over SW Manitoba overnight and advect eastwards into the Red River Valley before morning. No severe weather is expected.

Thursday

Thursday

24°C
Showers ending midday then cloudy with a few sunny breaks and a continued chance of showers.
Thursday Night

15°C
Showers with the risk of a thunderstorm overnight.

Thursday morning will start off rainy with the risk of a thunderstorm. Around 10–20mm of rain is possible however any higher amounts will likely be localized to any heavier patches of rain that develop. Things should taper off by midday leaving us with cloudy skies and perhaps a sunny break or two, but a chance of showers will continue through the afternoon.

Thursday night will start off cloudy then rain will push in by the late evening period as another cold front sweeps southwards from the central Prairies. Unfortunately, this area of rain will likely start off as thunderstorms over SW Manitoba.

NAM sounding valid on Thursday evening near Brandon, Manitoba.

NAM sounding valid on Thursday evening near Brandon, Manitoba.

Quickly looking at some of the convective elements in place:

  • MLCAPE values forecast to be in excess of 2000J/kg
  • 60kt 500mb jet will begin work it’s way into the region with the left exit of the jet poking into the Melita & Virden regions early in the evening.
  • A frontal boundary will be very close to the area providing convergence that can act as a trigger for storm initiation.
  • Falling heights through the upper atmosphere should help prime things for both initiation convection and to sustain anything that does manage to get going.

Low-level shear will not be favourable for the development of tornadoes, but the strong straight-line shear combined with ample moisture and relative low freezing levels will make large hail and torrential downpours a serious concern. Given the shear profile and the strength of the winds aloft, there may be a slight chance that these storms will develop strong straight-line winds. The main threat for severe weather will be over southwest and western Manitoba; at this point it looks like points from Virden to Minnedosa east to the lake then down along the shore-line to Portage face the biggest threat for severe weather, although not much would have to change to include Melita & Pilot Mound regions in there too. We’ll take a look at things a little later today and update this post with a severe thunderstorm outlook graphic if it seems applicable.

The thunderstorms will grow into an area of rain as they travel eastwards towards the Red River Valley. Here in Winnipeg we’ll still see the threat of a thunderstorm overnight, but it should mainly be rain – potentially heavy at times – amounting to about 5–10mm. If we see a thunderstorm than naturally the accumulations could be significantly more than that. The storms and rain should move out of the RRV into Northwestern Ontario overnight.

Friday

Friday

24°C / 15°C
Mainly sunny.

Mainly sunny skies will dominate on Friday as we move into a cooler, stable air mass in behind Thursday’s system. We’ll see the cooler weather persist for another day or so before hot weather begins working it’s way back into the area with temperatures looking to climb back towards 30°C on Sunday. The weekend looks gorgeous so get out there and enjoy it!

Saskatchewan Severe Storm Outbreak; Quiet in the Red River Valley

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We’ll move into a slightly quieter pattern after a low pressure disturbance moves through central Manitoba. This system is currently moving through western Saskatchewan and will produce a dangerous outbreak of severe thunderstorms along the Highway 11 corridor between Saskatoon and Regina today with torrential rain, hail possibly bigger than baseballs and a very real threat for an isolated tornado or two. The severe weather threat will be mostly confined to Saskatchewan today unlike Saturday when the substantial severe storm threat was expected to push into SW Manitoba.

Today & Tonight

Monday

30°C
Clearing then mainly sunny.
Monday Night

20°C
Cloudy periods with a chance of showers.

We’ll see a beautiful day toaday in the Red River Valley with sunny skies dominating after a few isolated showers move out of the area this morning. We’ll see temperatures climb to around 30°C this afternoon before some clouds move in in the evening ahead of the storms moving out of Saskatchewan. There will be a slight chance of showers tonight through the Red River Valley along the tail end of a thunderstorm complex that will be moving through the Interlake. As the low pushes across central Manitoba, the Red River Valley will move into the warm sector of this system, bringing much warmer, more humid air into the region. Thanks to this, we’ll see overnight lows quite a bit warmer than the past couple nights. We’ll eventually drop to around 20°C with noticable humidity.

Severe thunderstorms will move into western Manitoba this evening along a dryline pushing eastwards out of Saskatchewan. Storms are expected to stay well north of the Trans-Canada Highway, moving more through the Dauphin & Minnedosa areas then pushing eastwards into the Interlake overnight as an MCS capable of producing large hail and strong damaging winds. The storms will have trouble moving southwards thanks to a layer of dry air in place over the Red River Valley that will likely either kill or substantially weaken any weather that tries to push our way.

Tuesday & Wednesday

Tuesday

27°C / 15°C
Clearing then mainly sunny.
Wednesday

27°C / 15°C
Sunny with cloudy periods.

We’ll see more stable weather for Tuesday & Wednesday as a surface ridge begins working it’s way into the province. A fairly light northwesterly wind will kick in on Tuesday morning which will slowly push out much of the humidity in place over us making this feel quite a bit more comfortable outside. Wednesday will bring more sun than cloud with daytime highs pretty much the same as Tuesday. There will be a slight chance of light showers near the International Border through the period but no significant accumulations are expected.