Unseasonable Warmth Brings Chance of Rain

Brad Leave a comment

Unseasonably warm air will remain in place over Southern Manitoba for another day before a disturbance pushing eastwards across the Prairies brings a chance of rain and more seasonal temperatures for Tuesday. The “cool-down” will be short lived as above-seasonal temperatures are expected to return on Wednesday.

For the 42nd Canadian general election today, weather couldn’t be nicer for late October in Winnipeg. Today will bring plenty of sunshine and light winds with a high near 15°C.1 Temperatures will be cool tonight at around 2°C under increasing cloudiness.

RDPS 3hr. QPF forecast for late Tuesday afternoon.
The RDPS shows precipitation pushing into southern Manitoba late Tuesday afternoon.

Tuesday will be a mainly cloudy day with a cool northeast wind limiting our high to a more seasonal 9°C or so. There will be a chance of some shower activity through the afternoon and overnight period as a trough of low pressure pushes across the region, however amounts from the precipitation are expected to be fairly minimal with just a couple mm likely at most. With cloudy skies overnight, the low temperature will be kept a bit warmer at around 4°C.

Wednesday will see a return of the warmer weather.  Skies will clear through the morning hours letting the sun work a little bit of it’s late-season magic and bring us towards a high near 11°C with relatively light winds.  Expect a low near the freezing mark on Wednesday night under clear skies.

Long-Range Outlook

The second half of the work week looks quite pleasant with mainly sunny skies Wednesday & Thursday and warmer-than-seasonal daytime highs in the low teens.  Many weather models show a large low pressure system ejecting northeastwards out of Wyoming on Thursday night and pushing through Southern Manitoba on Friday, bringing a swath of rain across the region. There’s still quite a bit of uncertainty associated with that system, though, so we’ll keep eyes on it as the week goes on and take a closer look at it in our mid-week forecast!

  1. This is 7°C above the seasonal high temperature of 8°C for this time of year.↩

A Quick Return to Seasonal Conditions; Windy End of Weekend

Brad 1 Comment

Today is off to a cold start after a cold front passed through the Red River Valley yesterday morning, ushering in winds up to 70km/h and some mixed-phased showers as the cooler air mass moved into the region. The cool-down will be short-lived, fortunately, as seasonal to above-seasonal temperatures will return for today & through the weekend.

Today and tomorrow’s dominant weather feature will be a ridge of high pressure that will move through the region over the coming two days. With it in place, daytime highs will be cool at a seasonal or slightly below-seasonal 9–10°C. Winds will be light, and both tonight and tomorrow night will see overnight lows dipping below the freezing mark to around –2°C.

GDPS Surface Wind Forecast for 18Z Sunday October 18, 2015
The GDPS surface wind forecast for midday Sunday shows a core of stronger winds as a result of the outflow from the ridge of high pressure to the east.

Sunday will see a sunny start to the day, but a bit of cloud push in for the evening and overnight hours. The biggest weather issue of the day will be strong southerly winds that develop as surface winds accelerate out of the ridge of high pressure to our east and are aided by the strong temperature gradient as warmer air moves in aloft.[1] As such, winds will increase–likely midday–to around 40–50km/h out of the south with some gustiness on top of it. It won’t be severe-level winds, but it will certainly be a windy fall day. Temperatures will be slightly warmer at around 14°C, kept lower than the air moving in over us would suggest by the cool outflow winds at the surface.

The winds will taper off in the evening and temperatures will head to around 6°C for an overnight low under partly cloudy skies.

The Week Ahead

Next week is looking fairly unremarkable for the most part. There appears to be a slight chance of some rain mid-week, and other than that, it’s nothing but sunny to partly cloudy skies and seasonal to slightly above-seasonal temperatures. Lovely weather for the second half of October.

  1. Additionally, multiple models indicate the likelihood of enhanced anticyclonic curvature to the pressure gradient over the Red River Valley which, if true, will act to enhance the wind speeds.  ↩

Mild Weather Gives Way to Blustery Cold Front

Brad Leave a comment

The warmer-than-seasonal warmth in place over Southern Manitoba will last just one more day before a cooler air mass works its way into the region behind a cold front that will push through on Thursday.

Today will bring seasonal weather to Winnipeg & the Red River Valley, albeit with a bit of a breezy wind. Under mainly sunny skies, the temperature will climb to around 15°C, which is nearly 5°C above the seasonal average high of 11°C for this time of year. Winds will pick up through the day and be fairly windy out of the northwest with sustained winds climbing to 30–40km/h with gusts to around 50km/h.

Temperatures will dip to around 4–5°C tonight with skies becoming partly cloudy before morning.

Thursday will be quite an unpleasant day that will see a cold frontal passage that will bring in blustery winds and falling temperatures. The day will start off with partly cloudy skies and temperatures climbing to around 10–11°C by midday. Winds will be windy out of the northwest at around 30km/h with some gustiness on top of that. As the cold front passes through in the afternoon, we’ll see mixed-to-cloudy skies develop with a very slight chance of some showers along the front as it passes through. No significant accumulations are expected. Winds will remain blustery with winds remaining at 30–40km/h with gusts as high as 60km/h.

Animated 850mb Temperature Forecast for Thursday
Looking at the forecast 850mb temperatures, the passage of the cold front on Thursday is quite obvious.

As the front passes through, temperatures will drop to around 6°C in the Red River Valley. They’ll continue to drop as winds taper off and skies clear, heading towards an overnight low near –2°C.

Friday will be a pleasant, but cool, day. Winds won’t be much of an issue and temperatures will climb to around 7°C under mainly sunny skies. The low on Friday night will once again be around –2°C under clear skies.

Unremarkable Weekend Ahead

Looking ahead to the weekend, there doesn’t appear to be much to say about it. Through the weekend temperatures will climb back towards seasonal values with a bit of wind on Sunday. No significant precipitation is in store for the region.

Next week looks to have a bit of variability to daytime highs and a couple chances for rain as a slightly more unsettled pattern develops.

Hang onto your Hat! Severe Wind Storm for Thanksgiving Monday

Scott Leave a comment

It will be a very windy Thanksgiving as a strong low pressure system ushers in potentially damaging winds. By the time you’re reading this your loose objects will probably already be in your neighbour’s yard!

Monday

Today will not be the most pleasant Thanksgiving, as rain and strong winds wreck havoc outdoors. A strong low pressure system and corresponding pressure gradient will generate high to extremely high winds over southern Manitoba on Monday. The highest winds are expected Monday morning, when sustained speeds of 60-80km/h, and gusts to 100km/h or more, are expected. The period of extreme gusts likely won’t last more than a few hours, but during that time it will certainly do some damage, not to mention the fact that you’ll have a lot more leaves to rake!

A strong pressure gradient (shown above as tightly packed black lines called isobars) will bring very windy conditions to southern Manitoba on Monday
A strong pressure gradient (shown above as tightly packed black lines called isobars) will bring very windy conditions to southern Manitoba on Monday

Today will also be rather soggy, as moderate rainfall occurs in association with this low pressure system. Today’s rainfall amounts will likely be around 5-15mm in the Red River Valley. You’ll have to wait until at least Tuesday for all those wet leaves to dry out!

Tuesday

Tuesday will be much calmer than Monday. Temperatures will climb into the mid teens under mainly sunny skies. Winds will remain breezy from the west, but they will feel light compared to Monday!

Wednesday

Wednesday will feature much the same weather as Tuesday. Temperatures will be in the low to mid teens under mainly sunny skies. Winds will be breezy from the north-west, but once again it will feel like nothing compared to Monday.

Long Range

Long range models continue to show a strong signal for warmer than normal weather through the end of October. Hopefully this will continue to be the trend as we move into winter due to the effects of El Nino.