Tag: Rain

Warm Late-Summer Weather Continues

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A persistent southerly flow over southern Manitoba will keep the seasonably warm and humid conditions in place for a for a few more days.

RDPS 2m Temperature Forecast valid 21Z Wednesday September 18, 2024
A stalled low over eastern Montana will continue to pump warmer air northwards into southern Manitoba this week.

A quick note to start: the lack of forecasts last week was due to the fact that I’m dealing with a long-lasting bout of COVID–19 that’s sidelined me for a while now. I’m on a [gradual] up and up now, with symptoms finally receding after testing positive on rapid tests for a whopping 11 days in a row. Not a fun time, looking forward to getting back at life.

Daytime highs in the mid-20s will continue into mid-week for the Winnipeg area as a persistent low pressure complex to the west supports a southerly flow across the region. Daytime highs for Tuesday and Wednesday will likely sit around 25 °C; it could be a touch cooler if a bit of a stronger cold pool is left behind from overnight convection, or a tad warmer if we clear out early and a stronger southerly flow can develop earlier in the day.

The humidity will also be notable for mid-September, with dew point values in the mid- to upper-teens, potentially reaching around 20 °C on Wednesday. This is more humid that the region often sees at this time of year, but the lower daytime highs in the 20s should keep the worst of the heat effects at bay. In the sun, the heat and humidity could combine to feel like it’s in the low 30s rather than mid-20s.

RDPS 2m Dew Point Temperature Forecast valid 21Z Wednesday September 18, 2024
In addition to the seasonably mild temperatures, it will continue to be humid across southern Manitoba.

Overnight lows both tonight and tomorrow night will sit in the mid-teens.

Weather-wise, today should bring clearing skies as the disturbance that brought rain and thunderstorms to the region yesterday pushes off to the east. A few clouds will begin to build back in tonight, leading to mixed skies on Wednesday as a cold front approaches the region from the west.

A few showers are possible on Wednesday; it looks like they should be weak, though the slow-moving nature of the cold front and broad forcing could result in a narrow band of slow-moving showers that could produce some locally higher amounts in the 15 to 25 mm range. I’m doubtful Wednesday will be a “wet” day, more likely a cloudier one with the chance of passing showers.

The cloudiness and chance of showers will continue into Wednesday night.

Unsettled End to the Work Week

The low that’s been sitting to the west all week will finally get moving on Thursday, moving into southwest Manitoba on Thursday and sliding into northern Manitoba on Friday.

This will bring a notable change in the weather to southern Manitoba. To start, both Thursday and Friday could bring wet conditions to the Red River Valley. On Thursday, showers and thunderstorms will begin possible through much of south-central and southeast Manitoba as the forcing along the cold front picks up with the advance of the low. This activity will likely continue into the night as it pushes northeast.

Winds will finally shift on Thursday from the persistent southerly at 20 to 30 gusting 50 km/h seen much of this week to westerly winds of 15 to 30 km/h.

On Friday, showers in the instability on the back-side of this system may clip through southern Manitoba as cooler air moves into the region. Daytime highs will cool into the low 20s by the end of the work week.

Long Range Outlook

Heading into the weekend, more settled conditions will develop over the region as near-seasonal temperatures return. Winnipeg will see partly cloudy conditions over the weekend with daytime highs in the upper teens and overnight lows near the 10 °C mark.

This trend looks to continue into the start of next week.

Today’s seasonal daytime high in Winnipeg is 18 °C while the seasonal overnight low is 6 °C.

Hot Weather Before a Big Cool-Down

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There will be a couple more hot days in Winnipeg before a cold front sweeps through the province and ushers in much cooler conditions for a few days.

RDPS 2m Temperature Forecast valid 21Z Tuesday September 3, 2024
Southern Manitoba will have another couple days of warm weather before a strong cold front pushes through the region.

A weak upper ridge building east across the Prairies will bring warm weather to southern Manitoba over the next couple days. In Winnipeg, temperatures will climb to a sunny high near 30 °C today and into the mid-20s on Wednesday. Southerly winds of 30–40 km/h will build into the region today and ease into the 20–30 km/h range tonight. Temperatures will dip down to an overnight low in the upper teens tonight.

A trough of low pressure will move through on Wednesday morning, bringing mixed skies and lighter winds. Skies will clear through the day with northwest winds up to 30 km/h developing for the afternoon. There may end up being a low chance of isolated afternoon showers or thunderstorms, but it does not look likely right now.

A more substantial pattern change will occur on Wednesday night, marked by a strong cold front that pushes into the region overnight. This will bring northerly winds up to 40 gusting 60 km/h to the region as a colder air mass moves in. The cold front will bring a chance of showers to the region on Wednesday night into Thursday morning. Temperatures will head to a low in the low teens on Wednesday night.

Much cooler conditions will move into the region on Thursday, marked by an Arctic high building across the Prairies. Temperatures will struggle back to the mid-teens on Thursday with cloud cover breaking up through the day.

Temperatures will head down into the mid-single digits on Thursday night with clearing skies and easing winds.

Long Range Outlook

Friday will bring more cool weather to the region with sunny skies and a high in the upper teens. It iwll be another cool night with lows in the mid-single digits on Friday

Light southerly winds will redevelop on the weekend, marking the start of a gradual trend towards warmer weather. By next week, the region will be back to daytime highs in the mid- to upper 20s and overnight lows in the low teens.

Today’s seasonal daytime high in Winnipeg is 21 °C while the seasonal overnight low is 9 °C.

Weather Settling Through the Weekend in Southern Manitoba

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Seasonal temperatures will return to southern Manitoba as a ridge of high pressure begins to build into the region from the west.

RDPS 10m Wind Forecast valid 21Z Saturday August 31, 2024
A passing disturbance will usher in moderate northwest winds across southern Manitoba on Saturday.

Warmer temperatures return to Winnipeg and area today as westerly winds continue across the region. Daytime highs will climb back into the mid-20s today as warmer weather bounces back into the region behind the low that moved through yesterday. The wind will be persistent out of the west today near 30 gusting 50 km/h, then ease in the evening. The entire region will see plenty of sunshine today.

The low tonight will dip down into the low teens.

On Saturday, an upper-level disturbance will rotate through the region, bringing mixed skies to the region and a chance of showers. The rain looks to mainly stay north of Winnipeg with decreasing likelihood further south. As the disturbance passes through, it will usher in moderate northwest winds up to 40 gusting 60 km/h across the Red River Valley. This will keep daytime highs near-seasonal in the low 20s.

There is a chance with both the tail end of the westerlies today and the northwesterlies on Saturday that smoke may move into the Red River Valley. It’s unclear how thick any of those smoke plumes would be, though it looks more likely that Saturday would bring a more noticeable smoke plume into the region for a time.

The winds will taper off on Saturday evening with clearing skies and an overnight low that dips into the upper single digits.

A broad ridge of high pressure will move across southern Manitoba on Sunday, bringing light winds, clear skies, and seasonal highs in the low 20s.

Long Range Outlook

A southerly flow will redevelop early next week and bring warmer weather back into the region with highs climbing back into the upper 20s. It does not look like there will be an appreciable chance of rain in the first half of the week, but the chance for mid-week thunderstorms can’t be ruled out at this point.

Enjoy the weekend!

Today’s seasonal daytime high in Winnipeg is 22 °C while the seasonal overnight low is 10 °C.

Seasonably Cool Temperatures Ahead, Chance of Rain for Thursday

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In a stark contrast to the past weekend, a ridge of high pressure will keep temperatures seasonably cool much of this week. A passing low pressure system will bring milder temperatures on Wednesday followed by a chance of rain on Thursday.

RDPS 2m Temperature Forecast valid 21Z Tuesday August 27, 2024
Seasonably cool temperatures will sit over southern Manitoba today while warmer weather builds back into the western Prairies.

An Arctic high trundling east across northern Manitoba will keep temperatures cool and the humidity dry today. A disturbance rolling across North Dakota towards Lake of the Woods will bring cloudy skies into the region later this morning. Combined with a light northeast wind, daytime highs will be cool at around 20 °C in the Red River Valley.

Skies will clear this evening as the disturbance heads off into Ontario. The Arctic high will trundle towards James Bay, shifting the light winds in the Red River Valley southerly. Temperatures will dip down to a low near 10 °C.

On Wednesday, the next weather system to impact the region will begin taking shape. A vigorous upper-level disturbance will move from the British Columbia interior into today to southern Alberta by Wednesday. As this tracks east, it will pump much warmer air back into Saskatchewan as a low pressure system develops over the central Prairies. By Wednesday morning, a low will sit over central Saskatchewan with a warm front that drops southeast across southern Manitoba and a cold front southwards towards the Montana/North Dakota border.

This system will bring southerly winds to Winnipeg on Wednesday up to around 30 gusting 50 km/h. Temperatures will be warmer with highs in the mid-20s under mainly sunny skies. In the evening, a low-level jet — a corridor of fast-moving air about 1.5 to 3 km above the ground —will develop with wind speeds around 60 km/h (30–35 knots). These will help develop and sustain a band of showers and thunderstorms through the night that extend from North Dakota northwest to central Saskatchewan. For areas in southern Manitoba, there will be a low risk of a severe thunderstorm on Wednesday night with large hail and wind gusts the main hazards.

24hr. Precipitation Accumulation Forecast valid 00Z Friday August 30, 2024
One model’s forecast for daily rain accumulations on Thursday; while likely too widespread, it shows that showers are possible across much of southern Manitoba on Thursday.

Temperatures will dip to a low in the mid- to upper-teens on Wednesday night with moderate southeast winds continuing.

The band of [thunder]showers will reach Winnipeg either late overnight or early Thursday morning, then sunny breaks will develop after they pass as winds shift westerly. Temperatures will climb back up to the low 20s with mixed skies and a chance of more showers in the afternoon.

Temperatures will head to a low in the mid-teens on Thursday night with partly cloudy skies and west-northwest winds of 20 to 30 km/h.

Long Range Outlook

Settled conditions will redevelop for the end of the week and into the weekend as the mid-week disturbance heads off. A ridge of high pressure will build in from the west and bring settling conditions and sunnier skies.

Daytime highs should sit in the 20 to 25 °C range through the weekend with overnight lows slumping from the mid-teens to around 10 °C.

It’s a pretty pleasant forecast, and will be a nice recovery from the intense heat and humidity the region experienced over the weekend. I hope families with kids can get out there and enjoy the final days of summer before school kicks off again!

Today’s seasonal daytime high in Winnipeg is 24 °C while the seasonal overnight low is 10 °C.