Tag: Unsettled

Unsettled Start to the Week

Scott Leave a comment

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.

NAM Simulated RADAR Reflectivity
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.

Warm & Unsettled Weather

Brad Leave a comment

The weather over the next couple days will be two things: warmer than normal for this time of year and somewhat unsettled. While no major rain-makers are expected, a couple rounds of showers will make for some damper spells. Fortunately, daytime highs near 20°C will be above the seasonal 17°C through the weekend!

Friday
22°C / 12°C
Mixed skies; chance of showers or thunderstorms

Saturday
20°C / 10°C
Mixed skies; chance of showers or thunderstorms

Sunday
20°C / 10°C
Mainly sunny

Today will bring mixed skies to Winnipeg as a broad trough of low pressure works its way across the province. There will be a slight chance of showers this morning if any of the overnight activity manages to linger on and/or push far enough north, however nothing significant is expected. We’ll see mixed skies heading into the afternoon with a high near 22°C with winds tapering off to light.

The RDPS is forecasting a line of thunderstorms along the advancing cold front this afternoon.
The RDPS is forecasting a line of thunderstorms along the advancing cold front this afternoon.

Later in the afternoon the threat of showers or thunderstorms returns as a weak cold front begins slumping southwards. Severe weather doesn’t look likely, although if stronger thunderstorms manage to develop some marginally severe hail could be a possibility.[1]

Skies will clear out a bit in the evening and we’ll be left with partly cloudy skies on our way to a low of around 12°C.

Saturday will start off with just a few clouds around. We’ll warm up to around 20°C for an afternoon high with winds gradually increasing out of the west-northwest to around 20–30km/h. By mid-to-late afternoon the threat for shower or thunderstorm activity will increase as a shortwave sliding down in the northwest flow aloft begins triggering activity over Parkland Manitoba and the Interlake. That activity will slide southeastwards through the afternoon into the evening with scattered showers or thunderstorms looking fairly likely.

This map of a feature called vorticity – essentially a measure of spin – shows a potent shortwave moving across Southern Manitoba on Saturday afternoon.
This map of a feature called vorticity – essentially a measure of spin – shows a potent shortwave moving across Southern Manitoba on Saturday afternoon.

Some thunderstorms may be surprisingly strong given the relatively meagre convective indices for the day. The key will be the favourable storm-relative winds in place. Suitable turning will be in place that it’s possible — not necessarily likely, but possible — for an isolated supercell or two to develop with strong winds and large hail being the primary threats.

Skies will clear out on Saturday night as we drop to around 10°C.

Sunday will be a nice day with not a whole lot to say about it! A ridge of high pressure moving into the province will bring clear skies and relatively warm temperatures with a high near 20°C. The temperature on Sunday night will drop to around 10°C.

  1. Environment Canada considers severe hail to be 20mm or larger in diameter.  ↩

Summer Weather Turns Unsettled at Weeks End

Brad Leave a comment

Southern Manitoba is in the middle of one of the most pleasant stretches of summer weather so far this year; humidity is relatively low with plenty of sun and daytime highs sitting in the mid-to-upper 20’s. This beautiful weather will continue for another couple days before an upper-level low pressure system begins impacting our region on Friday, bringing unsettled weather back to the region.

Wednesday
26°C / 13°C
Mainly sunny

Thursday
26°C / 18°C
Mixed skies with a chance of showers in the evening

Friday
26°C / 15°C
Chance of [thunder]showers

Today and tomorrow will both be beautiful days with highs around 26°C and light winds as a ridge of high pressure moving through the province quashes any unwelcome weather. Both days will also feature ample sunshine and fairly light winds, although around the end of tomorrow winds will likely begin to pick up out of the southeast to around 20–30km/h. Tonight’s overnight low will hover around 13°C.

Thursday evening will mark the arrival of the leading edge of a major low pressure system developing over the western Prairies. A leading disturbance will swing into Southern Manitoba through the night, bringing a good chance of shower activity to most places[1] with around 5mm of rain expected in most places that see the showers. It may end up being more hit and miss and we’ll be able to refine the forecast as we get closer to the event.

A moderate risk of severe thunderstorms this afternoon will translate into a slight risk over SW Manitoba this evening.
A moderate risk of severe thunderstorms this afternoon will translate into a slight risk over SW Manitoba this evening. See our discussion below.

Perhaps of heightened concern for Thursday evening is the potential for severe thunderstorms over extreme Southwestern Manitoba. It’s worth being aware of the potential at the moment, however there are a lot of potentially complicating factors that will become clear tomorrow as to whether or not that threat will be able to be realized or not. We’ll update in the comments below with more details early in the day on Thursday.

Friday will bring unsettled weather. While morning showers will be possible, the weather will transition into a mix of sun and cloud fairly early before the threat for showers or thunderstorms redevelops in the afternoon. The redevelopment will not affect all of Southern Manitoba; it will mainly be of concern for the Red River Valley/Interlake and areas eastwards. Despite the unsettled weather, temperatures will be warm with highs sitting near 26°C. The humidity will be a little more noticeable, but nowhere near the humid days we’ve had so far this year.

Mixed Weekend

Looking ahead to the weekend, Saturday looks like showers will push through the region through the day underneath the upper-level low as it pushes through. Highs on Saturday will once again be in the mid–20’s. Sunday will be a return to pleasant weather as a ridge of high pressure begins building back into the area. Highs will likely be, you guessed it, in the mid–20’s!

  1. Including the Parkland region, southwest Manitoba, the Red River Valley, southeastern Manitoba and the Interlake.  ↩

Unsettled Week Ahead

Brad Leave a comment

Summer weather will continue to elude us as a complicated weather pattern is set to bring more unsettled weather this week. A series of moderate to strong disturbances will move through Southern Manitoba, each bringing a chance for rain. The first major disturbance looks to move through on Tuesday, with a second major disturbance coming through on Wednesday night.

The forecast surface weather pattern on Monday afternoon
The forecast surface weather pattern on Monday afternoon

At this point it appears that each of these pieces of energy will just bring light to moderate rain to parts of southern Manitoba. However, there is always the potential for heavier amounts if convective elements (i.e. thunderstorms) become embedded within the larger area of rain. These disturbances will be coming in from the south-west along a strong jet stream.

This strong jet may also be the focus for severe thunderstorms in the US Great Plains this week, so you may wish to keep tabs on that if you’re a thunderstorm enthusiast!

Monday

Monday
12°C / 5°C
Mix of Sun and Cloud

Today will be seasonably cool, with high temperatures in the low teens. Skies will be a mixture of sun and cloud to mainly cloudy, but at least no precipitation is expected. There will be a breezy south wind during the day, but it shouldn’t be quite as windy as it was on the weekend.

Tuesday

Tuesday
15°C / 6°C
Mainly Cloudy. Showers.

Tuesday is expected to feature showers in much of southern Manitoba. There is also a slight risk of a thundershower, which may lead to isolated pockets of heavier rain. Temperatures will be in the low to mid teens with a south wind once again.

Wednesday

Wednesday
15°C / 2°C
Mainly Cloudy. Chance of Showers.

Wednesday will be, you guessed it, unsettled once again, with the threat of showers remaining in southern Manitoba. Temperatures will be in the low teens, with a light northerly wind.

Long Range

The long range forecast suggests we’ll see warmer temperatures this weekend. By warmer, we’re talking probably upper teens or maybe low twenties. It won’t be anything spectacular, but those values will feel quite warm considering the weather we’ve seen as of late.