Category: Forecasts

Warmest Weather of the Year so Far on Tap

Brad Leave a comment

This week will start out with the warmest weather we’ve seen so far this year.

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A surface high will bring a mild southwesterly flow to Southern Manitoba on Monday and Tuesday

Monday and Tuesday

Monday
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Mainly Sunny
22°C / 7°C
Tuesday
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Mainly Sunny
23°C / 5°C

Monday and Tuesday will be two very nice and very similar days. Both days will feature high temperatures in the low to mid twenties in Southern Manitoba with sunny skies. The wind will be from the south-west on both days and may become a bit breezy in the late morning and afternoon hours. Other than that there isn’t much negative to say about the start of the week…except that our first twenty degree weather of the year won’t fall on a weekend!

Wednesday

Wednesday
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Mainly cloudy. Chance of showers.
12°C / 3°C

A cold front will move through Southern Manitoba on Tuesday night, setting up cooler conditions for Wednesday. This will be a fairly strong front, but the lack of moisture ahead of it will mean little if any rainfall is expected as it passes. Temperatures on Wednesday are expected to be in the low teens with a strong north wind.

Long Range

The rest of this week looks to remain on the cooler side, with temperatures remaining in the teens on Thursday and Friday. By Friday conditions may rebound back close to seasonal values, but unfortunately models show an arctic high pressure system dropping south into our area just in time for next weekend.

Gradual Warm-Up on The Way!

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Omega Block over Eastern North America

500mb heights/winds on Friday night depicting the Omega Block over Eastern North America.

Southern Manitoba has been under the grip of below-normal temperatures yet again over the past couple days, but a shift in the storm track will allow warmer air to build into the region. A large omega block, pictured above demonstrating it’s namesake (the wind flowing around the blocking pattern looks like the greek letter omega: Ω), will inhibit eastwards motion of the large-scale pattern, so the big question is: when exactly is it going to warm up? Fortunately, it’s not going to take too long.

Large-Scale Pattern Shift

Typically when blocking patterns set up, weather remains rather stagnant for a lengthy period of time: the rain stays in more or less the same place (it’s forecast to rain for most of the next 6-7 days in eastern portions of Iowa) and the sunshine remains over similar places. In extreme cases, features such as Omega Blocks can result in catastrophic flooding or droughts as similar conditions persist for weeks on end.

Fortunately, that won’t be our story. The blocking pattern is slowly decaying, but the real driver for our change in temperature will be the future of the upper trough currently over Manitoba/Northwestern Ontario. It’s simple existence is quite an anomalous feature and has only been able to maintain it’s existence by a continual reinforcement of Arctic air. Over the next few days, though, the northern storm track is going to become more active as disturbances begin to ripple through the NWT and Nunavut. These features will strengthen the upper-level winds north of 60° and cut off the reinforcing cold air.

Without this cold air injection and with the sun continually climbing higher in the sky, the cold air in our upper trough will quickly be modified out. As the northern storm track becomes more active, the flow aloft across the Northern Prairies will become more zonal as well, which will help bring warmer air into the region, although an upper ridge is forecast to build in over the Southern Prairies, keeping our winds fairly light aloft. So what does all this mean?

Friday

11°C / 0°C
Sunny
Saturday

14°C / 3°C
Sunny
Sundy

18°C / 8°C
Sunny

What will be happening over the next few days, effectively, is the “bottling up” of winter once again, locking it north of a strong jet stream running through the Northern Praires/Southern Arctic. Warmer air will slowly build back into the region with temperatures returning to normal or just above normal by the end of the weekend. In addition to the warming temperatures, we’ll see nothing but sun sun sun!

Next Week

The trend looks to continue through next week, with temperatures climbing into the low 20’s and more sunshine prevailing. The next chance for any sort of precipitation looks not to be until maybe the end of the week. A warm, dry week will be good news for the flood situation in Southern Manitoba.

Cooler Weather Returns

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After a few days of tasting what actually amounted to seasonal weather, we’ll be back into a below-normal temperature regime through the rest of the work week. With little precipitation expected over the next few days, when will the warm weather return?

850mb Temperatures on Thursday Afternoon

850mb temperatures reveal a significant cold trough (blue colors) that will sit over Central North America bringing cooler temperatures to our region.

A rather strong Arctic high pressure system is building into the Prairies behind yesterday’s low pressure system that brought significant amounts of snow the Manitoba Parkland & Interlake regions while dumping 20–30mm of rainfall over the Red River Valley. While massive amounts of snow cover were lost over the weekend, portions of Western & Central Manitoba are looking decidedly whiter after as much as 30–40cm of snow fell on Monday and Tuesday.

Wednesday

1°C / -5°C
A few flurries tapering off this afternoon. Clearing overnight.

Here in the Red River Valley, the bulk of the precipitation fell as rain before switching over to light snow in yesterday evening. This morning we’re left with some flurries that, fortunately, shouldn’t really amount to much as they’re being formed in some lingering instability left behind the low pressure system that’s now pushed offshore into Hudson Bay. As the Arctic ridge builds in through the day, the increasing stability will slowly quash any remaining flurries. Temperatures will drop to around –5°C tonight as the cooler air continues to filter into the southern portions of the province.

Thursday & Friday

We’ll see the main axis of the Arctic ridge push through on Thursday which will keep our temperatures some 15°C below normal with a daytime high of only around 1°C under sunny skies. It will be another chilly night with overnight lows close to –5°C.

Thursday

1°C / -4
Sunny.
Friday

8°C / -1°C
Mainly Sunny.

With the ridge past us on Friday, milder air will begin to push back into the region. We can expect just a few clouds and temperatures beginning to climb back towards normal, but only topping out at around 8°C. The overnight low on Friday night will dip just below the freezing mark.

A Look To The Weekend

This weekend looks quite pleasant with temperatures rebounding back into the mid-teens. A weak cold trough aloft is expected to linger near the region, so our temperatures may end up in the low-teens instead of the mid-to-high teens if it ends up setting up a little further west or north than currently forecast. While a potent system looks to affect Grand Forks & Fargo through the weekend, current indications are that this system will stay well to our south, just pushing some light cloud cover into the Red River Valley & SE Manitoba. There’s a slight chance areas in extreme SE Manitoba, such as Sprague, may see a light shower or two through the weekend.

Return to Cooler Conditions

Brad Leave a comment

After a beautiful weekend we’ll unfortunately slip back into well below normal weather this week. This cooler weather will be triggered by the passage of a weather system on Monday.

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A weather system will bring rain to Southern Manitoba on Monday

Today

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Increasing clouds. Periods of rain in the afternoon-overnight.
12°C / 6°C

Today will be a fairly normal late April day. Temperatures will be in the low teens with a breezy south wind. Cloud cover will increase during the day, with there being a chance of rain beginning in the afternoon and lasting into the overnight period. This rain will be generated by a fairly strong, complex low pressure system moving through Southern Manitoba and North Dakota today. It is quite difficult to figure out what accumulations might be as the rain may end up quite showery & localized, but my guess would be around 10mm in general with locally higher amounts. The first shot of precipitation will push through in the afternoon as low-level jet over-running a weak warm front slides across the province. This precipitation will be convective in nature, meaning rainfall amounts could be fairly significant (10-20mm) in a short period of time and relatively localized. Those showers will clear out in the evening before a second batch of precipitation arrives with the main low center late overnight. Here in the Red River Valley, that means that we’ll likely see some more shower activity overnight.

Tuesday and Wednesday

Tuesday
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Chance of Flurries.
6°C / -2°C
Wednesday
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Mix of sun and cloud
3°C / -3°C

A cold front will swing through tonight, ushering in cooler temperatures for Tuesday. The showers tonight may transition into some flurries on Tuesday morning as this cooler air moves in. Fortunately, these flurries won’t amount to anything, but they will signal a shift back into unpleasant, below-normal conditions. On Tuesday we’ll only see high temperatures in the low single digits with similarly cool values on Wednesday.

Long Range

In the long range there is no sign of a shift towards a more consistently above normal pattern. It looks like we’ll see near normal conditions return around the weekend, with some days being a bit below normal, with others are slightly above normal. There is also no sign of significant precipitation in the long range, which is a good for the flood situation.