Beautiful Days Ahead

Beautiful weather will continue across southern Manitoba through the next few days as a ridge of high pressure works it’s way across the Province. Things will turn stormier heading into the weekend as a potent upper trough pushes inland from the Pacific.

Today & Tomorrow

Wednesday

25°C / 12°C
A few clouds in the afternoon.
Thursday

25°C / 12°C
Description

Over the next couple days mainly sunny skies will dominate as a surface ridge slowly works it’s way across the province. Unlike the past couple days where we’ve enjoyed sunny skies here in the Red River Valley while areas further north in the Interlake and Central Manitoba were stuck underneath extensive cloud cover & showers, pretty much the entirety of Manitoba will be seeing plenty of sun and temperatures in the mid–20’s. Today we’ll climb to around 24°C and probably climb a degree or two higher for Thursday. Overnight lows will be comfortably seasonal, dipping down to around 12°C.

Things will begin taking a turn on Friday, though, as a strong southerly flow develops which will begin to push heat and moisture northwards through the High Plains and into the Southern Prairies. While it looks like the end of the week will have quite a bit of thunderstorm activity in Saskatchewan, things aren’t quite as clear cut here. Let’s take a look at how things look to pan out for us right now.

Friday

Friday

23°C / 13°C
Increasing cloud with risk of a thunderstorm. Chance of thunderstorms overnight.

A strong southerly flow will develop on Friday as the upper trough begins it’s way inland. Winds will increase to around 40km/h up and begin to bring moisture northwards. This will feed into a broad area of low pressure working it’s way across the Prairies. With the strong feed of moisture streaming northwards, we’ll likely see increasing cloudiness fairly early in the day which will limit our daytime high to a few degrees cooler than today or tomorrow. At this point, no severe storms are expected in the Red River Valley although a few scattered thunderstorms may manage to pop up, especially over the western RRV; for severe storms conditions look to be far more favourable further west in Eastern Saskatchewan or extreme SW Manitoba where the apex of the 850mb warm nose will reside with it’s associated low-level jet. Conditions there look favourable for the potential development of severe storms, although it may get messy very quickly with linear upscale growth shortly after initiation. Since the conditions there don’t directly pertain to the Red River Valley, I’ll leave a discussion of the severe weather potential for that region in the comments below.

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Rainfall forecast for Friday night (Sat 00Z – Sat 12Z) from the GDPS.

The storms that fire Friday evening will continue through the night at least as a band of rain but more likely as an organized area of nocturnal thunderstorms. The low looks to lift northwards through the night before continuing eastwards, and the storms are expected to follow suit, moving ENE after initiation. At this point, it looks quite likely that Friday night will be a stormy night in the Interlake, however in the Red River Valley things are more uncertain. With much of the forcing lifting northwards, storms may have a difficult time surviving further south where lift will not necessarily be lacking, but not nearly as focused. Wherever the storms do go, the threat for severe storms will likely continue into the night. A strong 40+kt 850mb low-level jet will provide ample lift and moisture for the system and help maintain 1000+J/kg MUCAPEs through the night. The main threat with these storms would be large hail and the potential for strong straight-line winds.

We’ll keep a close eye on this system and have a more comprehensive look at it on Friday morning’s post. Until then, get out there and enjoy the beautiful weather!

Nice Start to the Week

This week will start out fairly nice, with the exception of some showers on Monday.

A weather system will bring showers to Manitoba on Monday

Monday

Monday

Mainly cloudy a chance of showers, then clearing.
21°C / 10°C

Today will be a mixed day weather-wise. Showers are likely in the morning as a strong upper-level jet stream induces lift over the area. These showers are expected to taper off by this afternoon, with clearing skies thereafter. Once skies clear, temperatures should warm into the low twenties.

Tuesday and Wednesday

Tuesday and Wednesday look to be fairly similar days in Southern Manitoba. Both days should be mainy sunny with temperatures in the mid twenties. The wind should be fairly light, making conditions ideal.

Tuesday

Mainly Sunny
25°C / 13°C
Wednesday

Mainly Sunny
25°C / 12°C

Late Week

The late week forecast is unclear at this point. A strong longwave trough[1] will come onshore late in the week. This trough may generate a series of thunderstorm days across the Canadian Prairies and Northern US Plains. At this point the location and timing of storms is not known, but more details on this situation will be available as the week progresses.


  1. A longwave trough is a large-scale dip in the jet stream that is usually associated with strong weather systems and/or severe weather outbreaks.  ↩

Elsewhere in Weather News: June 8th, 2013

Severe Flooding in Europe

Major flooding has swept across central parts of Europe where Slovakia, Germany and the Czech Republic have all experienced crippling flooding this past week due to extreme rainfall. Amounts of 75mm were widespread across that part of the continent, and near the Alps, significantly higher amounts of precipitation were observed (some as snowfall at higher elevations). A few reports of 150-200cm of snow were recorded in Austria and Germany at high elevations.

Flooding

Severe flooding in Passau, Germany where the Danube easily overflowed its banks. (Source: AFP)

Rivers such as the Danube and Elbe have reached levels last attained 11 years ago and are threatening or have already breached sandbag dikes in some areas. Over 300,000 sandbags and counting have been prepared and put in place to prevent both rivers from overflowing their banks. The threat of a flood has forced residents out of their homes – as many as 40,000 people have been forced to move away from the nearby dikes and up to higher ground. The flooding upstream also has residents in Hungary, especially Budapest, worried as the Danube River has not crested yet but is expected to reach its peak later this weekend. Dikes there are expected to hold if the current crest projection is correct; it is believed the crest will be about a foot below maximum capacity.

Unfortunately 17 people have already lost their lives to the rapidly rising floodwaters and damage estimates top the 15 billion mark. Crop damage is widespread across Germany where over 250,000 hectares have been flooded out.

The forecast for central Europe calls for some rain on Sunday, associated with a trough but these showers will be nothing near as significant as what was experienced last week.

Mixed Weekend Ahead

The warm, mostly sunny weather of the past few days will give way to more unsettled conditions as a low pressure system anchors itself in Central Saskatchewan allowing a trough to sit over Southern Manitoba as a second low works it’s way across the Northern Plains of the United States. Showers will try to get going across Southern Manitoba but their coverage will be heavily limited by a lack of upper-level support over the region.

Today


24°C / 12°C
Sunny with cloudy periods. Chance of showers or a thunderstorm in the afternoon.

We’ll start off with some lingering clouds this morning with a chance of a few scattered showers as the remnants of a weak cold front wash out over the Red River Valley. We’ll then see a bit of short-lived clearing before skies cloud up this afternoon once we get warm enough to get some convection going. There will be enough instability around to produce a few afternoon showers or perhaps even a weak thunderstorm or two. Lifted Index values will be sitting at only –1 or –2°C which represents only marginal instability and CAPEs agree with values only around 500–750J/kg.

With little forcing in the area, the most favourable area for showers or thunderstorms will be near subtle convergence features; in our case, that will mean near either the western escarpment of the Red River Valley or any lake breeze convergence lines that form to the north and northwest of the city. At the moment it’s looking like the most potential for a thunderstorm sits west of Winnipeg in the Red River Valley, but there’s certainly a chance we may see an afternoon thunderstorm here in the city. Aside from the potential showers & thunderstorms, it will actually be a fairly pleasant day. Winds will be fairly light through the day and we’ll be climb to a high near 24°C. Skies will clear tonight as we head to a low of around 12°C.

Saturday & Sunday

Saturday

23°C / 12°C
Increasing cloudiness then a few showers or rain.
Sunday

24°C / 12·C
Mix of sun and clouds. Showers likely southwest of Winnipeg.

After a sunny start, skies will cloud over on Saturday as a trough connecting a low pressure system in central Saskatchewan and a low pressure system pushing into the Dakotas. There will some showers ahead of the trough line that will push through the Red River Valley in the afternoon. Rainfall amounts won’t be anything significant, but a localized 5–10mm can’t be ruled out. We’ll see a high near 23°C and an overnight low once again sitting near 12°C under clearing skies. Sunday will be a mix of sun and clouds with showers likely south and west of the Red River Valley. The high for the day will be around 24°C with an overnight low into Monday morning of about 12°C once again.