Scott Kehler 🇨🇦

Frost occurred over most of southern Manitoba this morning, with a hard freeze in Western Manitoba. Some locations in Westman got as low as -10 C! #mbwx

It's definitely one of the cold spots around the city, but it accurately represents its location which is semi-rural. For that reason it's a good location for Winnipeg because it more closely matches the historical records, which would've also been in a much less urbanized environment.

However, The Forks only recorded a low of 2.4 C, meaning urban Winnipeg largely escaped the freeze. Due to Winnipeg's urban heat island, the growing season in the urban core is almost one month longer than at the airport.

The growing season officially ended in Winnipeg last night with a low of -2.1 C at the airport. The growing season was 152 days long, or the 4th longest on record. The longest ever was 157 days in 1963. It began this year on May 8th. #mbwx

There was a hard freeze in southern Saskatchewan this morning. Mankota, SK got all the way down to -10 C! Frost also occurred in Western Manitoba, with the lowest temperatures near the Saskatchewan border. Frost is likely again tonight in Westman - it will be patchy farther east.

I've created a Bluesky Starter Pack called 'Canadian Severe Storms Community'. Makes it easy to find and follow severe storm forecasters, researchers, chasers and enthusiasts in Canada!

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Please let me know if you'd like to be added or if you think someone else needs to be added.

I spotted some unusual mammatus clouds overhead this afternoon. They’re unusual because normally mammatus are associated with strong thunderstorms. In this case there are just some rain showers in the area. #mbwx

You are likely seeing the line of storms that is about 20 km east along highway 12.

Watching an area of thunderstorms that are developing over southeastern MB. These storms are being triggered semi-parallel to a stationary front over northern Minnesota. Should they continue to expand tonight, locally heavy rain is possible at they move slowly northeast. #mbstorm

This will be the last week of summer-like weather in southern Manitoba, with temperatures running about 10°C above normal. Conditions are expected to return to normal next week with highs sinking back into the mid teens. #mbwx

This map shows rainfall estimates from weather radar, which generally match well with gauge measurements.

Note: In some communities there were numerous measurements available. I took the largest verifiable measurement from each community for this summary. Data came from personal weather stations, CoCoRAHS, ECCC, and Manitoba Agriculture. #mbstorm

Here is a summary of rainfall totals from last night's storm:

Steinbach: 142 mm (5.6 in)
Kleefeld: 125 mm (4.9 in)
La Broquerie: 122 mm (4.8 in)
Niverville: 99 mm (3.9 in)
Sprague: 86 mm (3.4 in)
Marchand: 83 mm (3.3 in)
Blumenort: 52 mm (2.1 in)
Ste. Agathe: 49 mm (1.9 in)

Another series of training thunderstorms brought a flash flood to SE Manitoba overnight. Up to 150 mm fell in the Steinbach area. The swath of heavy extended from Niverville southeastward to the Ontario border. This rain gauge in Steinbach maxed out at over 5 inches (125 mm).

Not overly. It’s a similar phenomena to sun dogs. Any time there are high level clouds near the sun you could see a halo.

Yes it looks like it. Appears to be due to high altitude ice crystals refracting sunlight.

Yesterday was the "earliest" single-digit high on record in Winnipeg, as the temperature only reached 9.0 C:

Yes it does. It's quite likely that our average high temperature this summer would've been a bit warmer if not for the smoke.

The headlines this summer in Winnipeg were smokey and dry. Temperatures were very close to normal overall.

An early frost event occurred in Saskatchewan this morning. Numerous low temperatures were around or just below the freezing mark:

Indian Head: -0.6 C
Yellow Grass: 0.2 C
Coronach: 0.6 C
Broadview: 1.1 C
Estevan: 1.0 C
Weyburn: 2.2 C
Regina: 2.3 C
Moose Jaw: 2.4 C

We are excited that our peer-reviewed and report-based hail climatology for Canada has been published in the The Journal of Catastrophe Risk & Resilience. The climatology shows a maximum in hail occurrence along the Alberta foothills with secondary maxima in the BC interior and southern Prairies.

A tough night for dogs that’s for sure

Yikes, driving west of the city?

Not much fun for me either as I was dealing with a scared and drooling 100 pound dog for most of the night.

The result was torrential rain over a zone that ran roughly along and just south of the Trans-Canada Highway between Portage and Winnipeg. The first map in this post shows storm-total amounts from last night through this morning.

As storms developed, winds higher in the atmosphere carried them from west to east, causing the same locations to be hit repeatedly. Because the low-level jet remained in place for many hours, this process continued.

It appears that a strong low-level jet (strong winds in the lower atmosphere) reached nearly 100 km/h just 1-2 km above the ground in southwestern Manitoba. Farther north, this helped create a convergence zone that triggered storms in the Portage la Prairie area.

Training thunderstorms produced heavy rainfall exceeding 100 mm (4 inches) in southern Manitoba overnight. Training storms are analogous to a freight train, as storms repeatedly pass over the same location. But why did this happen?

Rains overnight varied widely because they were from thunderstorms. Some areas got over 100 mm, some areas nothing.

There is a risk of severe thunderstorms today in southeastern Saskatchewan and southwestern Manitoba. Any storms this evening also have the potential to produce tornadoes.

A much-needed rain event brought significant amounts to northern MB over the past couple days. Here are some storm totals:

Lynn Lake: 84.7 mm
Pukatawagan: 58.8 mm
La Ronge, SK: 54.6 mm
Tadoule Lake: 27.0 mm
Thompson: 23.9 mm
Snow Lake: 18.7 mm
The Pas: 18.4 mm
Flin Flon: 18.2 mm