Weekend outlook

The final weekend of May will finish the month with cooler than normal conditions along with a chance of showers Saturday night into Sunday morning. High pressure building in for Saturday will give a sunny but cool start to the weekend, with patchy frost early Saturday morning outside the city. Afternoon highs are expected to reach 15 or 16C, but light winds and sunny skies will make those temperatures feel warmer. A system tracking through southern Manitoba Saturday night will bring a few showers across southern MB Saturday night into Sunday morning, with even a chance of some scattered thunderstorms. The unsettled weather should move off Sunday morning leaving partly sunny skies and afternoon temperatures near 20C. So all in all, it shouldn't be too bad a weekend, but those waiting for summerlike weather will have to continue to wait. Model guidance is not suggesting any change to above normal conditions over southern MB through the next week or two. As for May, it looks like it will finish with a mean temperature around 8.3C at Winnipeg airport, some 4 degrees below normal, and the 15th coolest May since 1872.

Nice weekend.. heavy rain looms Monday for southern RRV/ND/MN

High pressure over southern MB is finally bringing a beautiful weekend over the area with sunny skies.. light winds and seasonable temperatures of 18c today and 21c Sunday. A great weekend to finally get that overdue landscaping started!

Attention then turns to a potentially heavy rainfall event that will be unfolding over North Dakota and northern Minnesota Sunday night into Monday that may affect southeast MB as well. A slow moving low pressure system with plenty of moisture feeding into the system will generate an area of slow moving showers and embedded thunderstorms Sunday night through Monday night over northeast ND, northern MN, possibly spreading into SE Manitoba mainly south and east of Winnipeg. Computer models are indicating that 50 to 75 mm is possible through this period, with the latest Canadian GLB model suggesting the Sprague area could be seeing 100 to 150 mm of rain Monday into Monday night! It is still too early to give precise details on location and amounts of rain with this upcoming system, but the potential exists for heavy rainfall over eastern North Dakota, northern MN, and the southern Red River basin through SE Manitoba Sunday night into Monday night. Stay tuned..

Thunderstorms possible this afternoon across Red River Valley/SE MB

A weak cold front will cross southern MB today bringing the threat of thunderstorms mainly along and east of the Red River valley this afternoon.  Conditions are unstable enough for small but fairly energetic thunderstorms to develop along and ahead of this cold front, with the potential for stronger storms to produce marble size hail. Storms should be moving fairly rapidly so heavy rainfall should not be a major concern.. although the storms may produce locally heavy downpours for a short period. The main threat of storms in Winnipeg will be between 1 and 3 pm, with the threat area pushing east of the city after that time as drier and more stable air pushes in from the west behind the front.  

Enjoy today.. sharply cooler tomorrow

Today will be the mildest day of the holiday weekend as gusty southerly winds push temperatures up to 18-20C over southern MB with morning sunshine giving way to high cloudiness during the day. A southerly breeze will keep temperatures mild tonight, with lows of 10-12C . Early Monday however, a sharp cold front will sweep across southern MB from the north, bringing strong northerly winds and falling temperatures. In Winnipeg, the front is expected to pass through between 5 and 8 am, dropping temperatures from sunrise values near 12C to about 5C during the morning, remaining steady or recovering only slightly in the afternoon. This will lead to a widespread frost Tuesday morning across southern MB with morning lows of –2 to -5C likely under clear skies and light winds.

Cooler than normal weather is expected for much of the upcoming week with showers possible Wednesday. The good news is that long range guidance is finally indicating a nice prolonged warmup by next weekend with temperatures in the 20s, hopefully taking us through the end of May.

Tis the spring of our discontent.. Heavy snow falls north of Winnipeg

An Alberta clipper system tracking through southern Manitoba overnight brought a swath of heavy wet snow through western MB and the Interlake.. just as people were looking forward to the unofficial start of summer this holiday weekend. The heaviest snow fell through the northern Riding Mountain area through Dauphin and the Lake Manitoba Narrows into the central Interlake where 20-30 cm of snow was reported. The photo here is from Dauphin which received about 20 cm of the white stuff overnight. Other snowfall reports included..

McCreary................ 30 cm
Grandview.............. 30 cm
Eddystone................ 30 cm
Roblin 3 NW............ 30 cm
Russell......................25-30 cm
Hodgson................... 27 cm (east of Ashern)
Gilbert Plains............. 24 cm
Bissett......................... 23 cm
Moosehorn.................. 20 cm+
Dauphin.................. 20 cm
Roblin...................... 20 cm
Laurier.................... 20 cm
Alonsa......................20 cm
Eriksdale................ 20 cm
Ethelbert................ 20 cm
Fisher Branch..........20 cm
Rossburn................... 14 cm
Inglis..................... 12 cm
Riverton................ 9 cm
Gimli......................7 cm

Further south of these regions, precipitation was in the form of rain although temperatures in the low single digits were well below normal for mid May. The system is quickly clearing out of the province today today and will be followed by drier and milder weather for Saturday and Sunday, before another cooldown for holiday Monday.

The satellite image here from the morning of the 16th reveals where the heaviest snow fell with this system. Note the white swath of snow across the Riding Mtns into the Interlake regions and east of Lake Winnipeg. A small streamer of snow also extended south of Lake Winnipeg through Beausejour.

Clipper to bring snow to western MB and Interlake.. rain south

An Alberta clipper will track through the Dakotas overnight and bring an area of rain and snow to southern MB tonight into Friday morning. Rain will spread into southern MB from the west tonight, but will change to snow over the higher elevations of western MB through the Riding Mountain and Duck Mountains areas. Snow will be heavy at times tonight in these areas with 10-20 cm possible, especially along the eastern slopes and over higher elevations. The highway 5 corridor from Dauphin to Roblin and Highway 10 corridor north of Hwy 5 through Ethelbert and Pine River are under the gun for heavy snow tonight. This snow will track east into the central and northern interlake regions overnight into Friday, bringing heavy snow to the Hwy 6 corridor mainly north of Lundar. Further south, precipitation will arrive in the form of rain tonight, with about 5-10 mm of rain possible in Winnipeg and the northern RRV overnight into Friday morning.

Thunderstorms possible late Tuesday

The season's first general threat of thunderstorms is possible Tuesday afternoon into Tuesday evening as a cold front approaches southern MB from the west. Temperatures near 20C along with dewpoints of 10-13C will provide the fuel for shower and thunderstorm development ahead of the cold front.. with favourable windshear giving the potential for locally strong storms giving heavy rain and large hail in some areas. Stay updated on these potential storms with comments on this blog thread, as well as GRlevel3 radar data and streaming video (if available) from local storm chaser Justin Hobson.

Say it ain't snow!

Winnipeggers started their weekend with a fresh coating of snow Saturday morning as an unseasonably cold airmass persists over southern MB. Snow will taper off this morning but cloudy and cold conditions will continue today before temperatures start moderating Sunday into Monday. Unfortunately a change to warmer drier weather pattern does not look likely in the near term as unsettled and cooler weather moves in again for the upcoming week.

April 2009 stats and snowfall summary

April 2009 finished with a monthly mean temperature of +3.3C at Winnipeg airport, 0.7C below normal of +4.0C. This makes April the fifth month in a row that has finished below normal, and the 11th of the past 15 months with monthly mean temperatures cooler than average. The main story for April 2009 was the absence of heat, rather than any major cold spells, that kept temperatures below normal. The highest temperature for the month was only 18C, the first time since 1997 that Winnipeg hasn't hit the 20C mark during April. The month started with a cruel April Fool's joke from Mother Nature with a 13 cm snowfall on the last day of March into April 1st. That was the last significant snowfall of the winter (we hope!) bringing the total seasonal snowfall for the winter of 2008-09 to 126 cm at my site, some 16 cm above the Winnipeg average snowfall of 110 cm.

Snowfall stats from 2008-09 - Charleswood
(Winnipeg averages in brackets)

October 2008.......... 0.0 cm (5 cm)
November 2008 ..... 15.0 cm (21 cm)
December 2008 ...... 28.2 cm (20 cm)
January 2009 ......... 28.6 cm (23 cm)
February 2009 ...... 14.0 cm (14 cm)
March 2009 .......... 35.0 cm (16 cm)
April 2009 ............ 5.6 cm (10 cm)

TOTAL................ 126.4 cm (110 cm)