Category: Forecasts

Strong Winds Blast Southern Manitoba

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Strong winds will blast across Southern Manitoba today as a very powerful low pressure system crosses Northern Manitoba. The winds will also usher in an unseasonably cool air mass that will give us a very chilly night before the upper ridge begins to rebound into our region.

850mb Temperatures for Thursday morning from the GEM-REG

850mb temperatures for Thursday morning from the GEM-REG. A cold trough of 850mb temperatures between 0-1°C will rest over the Red River Valley and Whiteshell, contributing to unseasonably cold overnight lows.

A powerful low pressure system with a central pressure of approximately 984mb is pushing across Northern Manitoba and will bring a very strong pressure gradient across the Red River Valley today that will usher in 50-60km/h winds with gusts as high as 80km/h. This system has a history of producing very strong winds; on Monday it brought widespread winds in excess of 100km/h to Southern Alberta and yesterday it brought winds between 80-110km/h through Saskatchewan and Northern Manitoba.

The winds will pick up in the Red River Valley this morning and we’ll see several hours of fairly strong westerly winds. Unlike regions to our west that had to deal with the winds for a fairly prolonged period of time, the winds will move through the region fairly quickly as the low accelerates out of Northern Manitoba into Hudson Bay. As a result, winds should let up noticeably by the evening.

In behind this system, fairly cold air will sweep across the province. Across the Red River Valley, overnight lows will be kept a little warmer by some light winds expected to continue through the night. Through the Red River Valley, overnight lows will generally drop to 3-5°C tonight, however if any areas see the wind let up, it would certainly be possible to see overnight lows dip to 1-2°C under clear skies and calm winds. The most likely area for this to happen, though, is a little further east in the Whiteshell where the trees will help protect the surface from light synoptic winds.

Temperatures will return to seasonal on Thursday as an upper ridge begins to build eastwards across the Prairies. We’ll see a mix of sun and cloud across the Red River Valley with a very slight chance of a shower as warmer air begins to push into the region. Daytime highs should be near 19-20°C on Thursday with overnight lows on Thursday night once again rather chilly in the 4-6°C.

Warm air moves back in for the weekend, with plenty of sunshine and highs near 25°C on Friday and Saturday. Things look to cool off a bit on Sunday as another cold front passes through.

The Week Will Start Hot! Then Fizzle…

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This week will start out with some nice hot weather, but then rapidly cool off from there. Fall weather appears to be here to stay.

Temperatures are expected to reach the 30C mark in much of Southern Manitoba on Monday

The NAM model is predicting that temperatures will reach the low thirties in much of Southern Manitoba on Monday

Monday will be one of our last hot days of the year as temperatures climb up around the 30C mark in Southern Manitoba. However, the heat won’t last long, as a cold front will sweep through on Tuesday, bringing cooler weather for the rest of the week. Temperatures from Tuesday through Friday are expected to be fairly typical for mid-September, with values in the upper teens or lower twenties expected. No significant precipitation is expected for the first part of this week, though an odd shower is possible.

At this point most long-range models don’t give a clear picture for how September will proceed temperature-wise. For the most part is looks like we’ll see many normal weather, with some ups and downs here and there. A more interesting long-range weather feature to watch is the development of El Nino conditions in the Pacific Ocean. Most long-term forecasts are calling for the development of weak El Nino conditions in the central Pacific Ocean for this fall and winter. El Nino events tend to bring warmer and drier than normal weather to Western Canada. The stronger the El Nino is, the greater the chance we’ll see a warmer and drier than normal winter here in Southern Manitoba. As we move into winter you will no doubt be hearing more about this topic.

Streamers This Morning; Seasonal Weekend

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After lake-effect streamers diminish this morning, we’ll see mainly sunny skies for the rest of the weekend with daytime highs near or just above 20°C.

GFS 500mb Wind Speeds

500mb wind speeds from the GFS model valid mid-day today. Faster winds are shaded. This clearly depicts how Winnipeg is in between the cooler air of the upper low, situated over James Bay, and the warmer air of the upper ridge/high, situated over the Western Prairies.

We’ll see clouds this morning with some showers over the Northern Red River Valley. These showers will be lake-effect streamers, so they’ll impact fairly long, narrow areas downwind of the lakes; where exactly will see showers will be highly dependent on the exact wind direction, so checking out where they are using our RADAR Viewer is your most reliable way to see if you’ll be impacted by them. Winnipeg will likely escape mostly unscathed from the streamers this morning, although should the wind shift to be a little more northerly (more favourable) or westerly (less favourable) we certainly could see some precipitation.

A ridge will slowly start building eastwards across the Prairies today which will bring a more westerly component into our winds across the province this afternoon and help start clearing out the clouds. By mid-to-late afternoon we should see sunny skies with a high right around 20°C here in Winnipeg. Tonight we’ll see clear skies with an overnight low dipping down to about 10°C.

Saturday will bring sunny skies and a high near 21°C as the ridge continues to try and build eastwards. A weak disturbance sliding SE across Manitoba will, however, pull some cooler air southwards across the province which will cause us to have our coolest overnight lows in quite a while across the Red River Valley. Here in Winnipeg, it looks like the overnight low will dip to 6 or 7°C in outlying areas, with temperatures a couple degrees higher near the core of the city.

Warmer air finally is able to push in on Sunday, which will give us a high near 24°C under sunny skies.

The beginning of next week looks to be sunny with slightly above-normal daytime highs.

Seasonable Weather with A Chance of Showers

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Feeling chilly after the weather we’ve had lately, more seasonable weather has returned to Southern Manitoba with a slight chance of showers tonight across most areas of the RRV.

The large captured upper low over Northern Manitoba

A GOES East multispectral satellite imagery from Tuesday evening showing the large captured low (denoted by the red L) anchored over Northern Manitoba.

A large upper trough is entrenched over Manitoba, bringing with it cooler air and clouds. Over the next several days, our temperatures will only climb to around the 20°C mark, right around the normal daytime high at this time of year of 21°C.

For today, temperatures will climb to about 23°C before the sky clouds over as a weak cold front passes and our winds increase out of the northwest to about 20km/h with gusts to 40km/h. Clouds will clear out in the evening and we’ll drop to a chilly low of 8°C.

Skies will cloud up again on Thursday as we struggle to hit 20°C. Well have a slight chance of showers through Winnipeg and the Northern RRV through lunch and the early afternoon, however it won’t amount to much if it does materialize.

Temperatures will slowly climb at the end of the week into the weekend. Friday will see mainly sunny skies with a high of 21°C as we have one more day under the influence of the upper trough. As we move into the weekend, warm air pushes in once again, and we should see above-normal highs near 25°C under sunny skies.