More Wet Weather on the Way

Scott Leave a comment

More rain is in store early this week as a well-developed low pressure system pushes across southern Manitoba. Accumulations will be relatively small in the Red River Valley, but more significant to the north and west.

A strong low pressure system will bring rain to southern Manitoba today
A strong low pressure system will bring rain to southern Manitoba today

This Week

Rain will move into southern Manitoba today in association with a strong low pressure system coming out of Montana. Light rain will likely begin in the Red River Valley this morning, continuing into the afternoon. Models show a break in the rain during the evening hours, which might just provide a good window for trick-or-treating. Regardless of whether it’s raining or not, temperatures will be favourable for the youngsters to be outdoors, with temperatures hovering in the mid-single digits. Total rainfall of 2-5 mm is expected today, with another 2-5 mm tonight. Parts of western Manitoba and the Interlake can expect total accumulations ranging from 10 to 25 mm.

Today’s weather system will still be lingering over Manitoba on Tuesday, with some showers remaining possible through Tuesday morning. A drier flow should develop by Tuesday afternoon, signalling an end to the precipitation. Temperatures will remain relatively normal for late October, with high temperatures in the mid to upper single digits in southern Manitoba. Winds will be breezy out of the west at 20-30 km/h.

Nicer weather should arrive for Wednesday as a ridge of high pressure builds over the region. Mainly sunny skies and temperatures around or just below 10C are expected. Wednesday’s nice conditions should signal the beginning of a significant warm spell which should last into next week. Winds should be relatively light thanks to the surface ridge.

Long Range

Medium- to long-range models have been strongly hinting at a significant warm-up beginning mid to late this week. An anomalously strong upper ridge of high pressure is expected to build over Central North America, signalling a period of well-above seasonal conditions for Manitoba. Given that our normal high is 4C, we can easily expect temperatures of 10-15C. It is not impossible that we reach the upper teens once or twice when the “heat” peaks sometime over the weekend or next week. Models strongly suggest that this above-seasonal pattern will exist for most, if not all, of the first half of November.

An unusually strong upper-level ridge will build over Manitoba by next weekend
An unusually strong upper-level ridge will build over Manitoba by next weekend

Friday’s Disturbance Leads To Cooler Weekend

Brad Leave a comment

Cooler, more seasonal temperatures will push into Winnipeg & the Red River Valley this weekend behind a low pressure system that will bring rain to portions of Southern Manitoba on Friday.

Today will bring a low pressure system, talked about in Wednesday’s forecast, through the province. In that post, we discussed how there was uncertainty in the track of the low, and that it seemed like much of the rain associated with it would fall across the Interlake. With the system imminent now, it’s become readily apparent that it will indeed primarily affect areas to the north of Winnipeg, at least for much of the day today.

Today will be a cloudy one across Winnipeg & the Red River Valley with light winds and temperatures climbing to a high near 12°C. Late this afternoon, winds will pick up out of the northwest to around 30 km/h, bringing with them a chance of some rain as a cold front sweeps southwards across the province. No significant accumulations are expected in Winnipeg, unlike the further north where 15-25 mm are possible along a west-east line running from Swan River eastwards across the Northern Interlake and Berens River.

With the gusty northerly winds and light showers tonight will come dropping temperatures. Lows should sit near 2°C tonight with winds tapering off towards Saturday morning. With the cooler temperatures and northwesterly winds, there may also be more persistent shower activity in the lee of Lakes Manitoba & Winnipeg as a result of weak lake-effect precipitation.

Light shower activity is expected across Southern Manitoba on Friday night.
Light shower activity is expected across Southern Manitoba on Friday night.

Saturday will be a mainly cloudy day with light winds and a much cooler, more seasonal high near 6°C. Expect continued cloud cover on Saturday night with lows near 1°C.

Sunday will start off cloudy but will likely bring an occasional sunny break in the afternoon. Temperatures will continue seasonal with a high near 8 or 9°C, but the wind will be more noticeable as it picks up out of the south to around 30 km/h once again. There’s a slight chance that it could end up even slightly windier than that, with sustained winds near 40 km/h, but at this point guidance suggests winds will be closer to the 30 km/h mark.

Expect a low on Sunday night near 5°C under partly cloudy skies.

Long Range

Guidance continues to be fairly consistent in a low pressure system moving through the province on Monday that will bring a soaking rain to much of Southern Manitoba. It’s a bit early for exact numbers, but general amounts 10-25 mm have been consistently produced by guidance over the past several days. After that system moves through, an upper ridge will build into the southern Prairies and…

NAEFS 8-14 Day Temperature Anomaly Forecast — Valid November 4, 2016 to November 11, 2016
NAEFS 8-14 Day Temperature Anomaly Forecast — Valid November 4, 2016 to November 11, 2016

Dry weather with an extremely high likelihood of above-seasonal temperatures will be on the way for Southern Manitoba, alongside much of North America, through the second half of next week. So hang tight, it looks like we have some beautiful November weather ahead!

Winnipeg’s seasonal daytime high is currently 6°C while the seasonal overnight low is -4°C.

Above-Average Temperatures Bring Wet Weather

Brad 1 Comment

Daytime highs will continue to be above the seasonal average of 6°C throughout the remainder of the work week, however it will come at a cost as a series of disturbances work across the region bringing multiple rounds of wet weather.

The first disturbance that will bring wet weather to Winnipeg is outside your window right now, as rain spread into the region overnight. The rain will taper off towards midday with a grand total of 5-10mm of accumulation likely for most areas.1 As the rain pushes off to the east, temperatures will climb to a high near 9°C under cloudy skies.

RDPS forecast rainfall totals for daytime hours on Wednesday.
RDPS forecast rainfall totals for daytime hours on Wednesday.

Tonight will bring some clearing to the Red River Valley, but the lack of any significant westerly flow to the winds will prevent us from seeing widespread elimination of the cloud, meaning skies will likely remain at least mixed over the region through the night. Temperatures will drop to a low near 4°C.

Thursday will leave the region in a slack flow with mixed to mainly cloudy skies. Temperatures will climb to a daytime high near 11°C in what will be a rather unremarkable day. The next disturbance will begin moving through the region on Thursday night, thickening up the cloud cover again as temperatures drop to a low near 6°C.

Friday is a bit of a wildcard at this point…at least for Winnipeg. A low pressure system tracking along the International Border will spread an area of rain to its north, however who exactly will see rain will be a bit of a challenged as the southern edge of the accumulations will see a rapid cutoff. Complicating things is relatively minimal model agreement:

Event Total Rainfall Forecasts for Winnipeg, MB – October 28, 2016
Model Event Rainfall (mm)
RDPS N/A
GFS 0.5
NAM 1.9
GDPS 3.9
PME 4.0
GEPS 8.8

So the range in precipitation amounts goes from the GFS’ low end forecast of 0.5mm, a situation where pretty much the entire area of rain falls north of the city, up to nearly 10mm from the global ensemble prediction system. It seems likely that the bulk of the rainfall with this system will fall north of Winnipeg, with the city seeing either some brief rain or more sporadic shower activity through the day.

The temperature should reach a high near 10°C while the overnight low drops to around 5°C under cloudy skies.

Long Range

The weekend is looking dry as seasonal air returns to the region with northerly winds on Saturday and southerly winds on Sunday. The chance for rain returns to the Red River Valley on Monday.

Winnipeg’s seasonal daytime high is currently 6°C while the seasonal overnight low is -3°C.

  1. A few locations along the western escarpment northwestwards into Parkland Manitoba may see total amounts in the 10-15mm range. ↩

Cloudy, But Mild

Scott Leave a comment

This week will start out on the grey side, with more clouds than sun on most days. However, temperatures will remain mild with values at or above seasonal norms.

Mild but cloudy conditions are expected in southern Manitoba today.
Mild but cloudy conditions are expected in southern Manitoba today.

This Week

Today will be a fairly typical late October day in southern Manitoba. Skies will remain mainly cloudy in most areas as a low cloud deck remains suck along the eastern edge of a surface ridge. Temperatures will be near seasonal values, with highs in the mid to upper single digits. Winds will be light from the east. There is a slight chance of a shower or flurry, but not significant accumulations are expected.

Tuesday will see temperatures warm slightly over today, but skies will remain grey. An approaching system will ensure continued cloudiness over southern Manitoba, but a stiff southeasterly flow will allow temperatures to climb up near 10C in most areas. That southeasterly flow will be gusting up to 50 km/h by the afternoon, making these slightly-above seasonal temperatures seem a bit chilly. Shower activity is possible during the day, with a better chance of rain Tuesday night into Wednesday as that system moves closer.

Wednesday will remain mainly cloudy with a continued chance of showers as a weak low pressure system slowly passes by. Temperatures will remain mild, near 10C, with gusty south winds of 20-30 km/h.

Long Range

Long range models show generally seasonal to above-seasonal temperatures as we move through the end of October. Our normal high for this time of year is 7C, suggesting that temperatures in the upper single digits or low double digits will be most common through month’s end. These warm conditions will likely spill into early November, but it remains to be seen whether or not November will see an early start to winter, or if we’ll have to wait a bit longer for the white stuff to come for good.