Mild weather continues Monday.. then turning colder this week with coldest airmass of the season moving in by Christmas

The relatively mild weather over the first half of December across southern MB will continue for one more day Monday, before significantly colder weather moves in this week. Even colder weather is expected by next weekend as the coldest airmass of the season so far pushes in across the Prairies for the Christmas holidays.

Temperature forecast for Winnipeg over next 10 days shows cold trend
setting in this week, with temperatures near -30C possible by Christmas
(graphic from weather.us)

In the short term, a westerly push of mild air will sweep across southern Manitoba Monday pushing temperatures up to the 0 to +1C mark over southern Manitoba, including Winnipeg. There may be some wet snow pushing across areas south of the TransCanada highway to the US border Monday morning through midday as a weak disturbance pushes through. In the wake of this system colder air will move into southern MB for Tuesday with temperatures dropping to the -10C mark by late afternoon. This will be the start of a period of much colder weather with temperatures near -20c expected by Wednesday morning. Highs Wednesday through Friday will only be in the minus teens with lows near -20C which is actually about average for this time of year (Normal hi -10C, low -20c)

Frigid weather expected for Christmas holidays

850 mb temperature forecast by European model for Christmas morning
shows massive Arctic vortex pushing across Manitoba with temps near -30C
(graphic from weather.us)

Unfortunately, things look to get even colder by next weekend just in time for Christmas as a massive push of Arctic air plunges south ushering in the coldest airmass of the season so far into southern Manitoba. This will bring daytime temperatures only in the minus 20s, with overnight lows  around -30C or lower.  Windchills may push into the warning criteria of -40 or lower at times over the Christmas holidays. Weatherwise, it looks mainly dry with no major storms or snowfall expected over the holidays with Arctic high pressure in place, so travel conditions should be okay across southern Manitoba. Otherwise, be prepared for frigid weather as you make your holiday plans!

Forecast temperatures Christmas morning shows widespread temps
of -30 to -35C across much of Manitoba with local -40C possible
(graphic from weather.us)

Surface map for Christmas morning shows massive Arctic high (1062 mb!)
over southern Saskatchewan driving frigid Arctic air across Manitoba
(graphic from tropicaltidbits.com)

Snow on the way Monday as pattern changing storm system impacts southern MB and NW Ontario. Colder weather to follow..

Forecast map valid midnight Tuesday shows strong winter storm system near
Thunder Bay with strong winds and snow on backside of system. Low will
track from South Dakota and increase in intensity as it heads northeast   

A storm system tracking across South Dakota tonight will move into Minnesota Monday and intensify as it heads into NW Ontario Monday night into Tuesday. This system is expected to bring snow to southern MB Monday, with the highest amounts expected near the Ontario border where 10-15 cm is expected by Tuesday morning. For Winnipeg and the RRV, 5 cm is expected with up to 10 cm for eastern and southern areas (Steinbach, Emerson, etc)  However, northerly winds are expected to increase Monday afternoon into Monday night which will lead to deteriorating conditions due to blowing and drifting snow with poor visibilities. Temperatures will also be falling into the minus teens Monday night with little recovery Tuesday. Cold weather is expected for the rest of the week before some moderation by week's end. So be prepared for a return to winterlike conditions for the new work week after a pleasant weekend and mild end to November.  

Mild weekend will give way to colder weather next week as upper pattern shifts

The mild weather of the past week or two will continue for the upcoming weekend.. but changes are brewing by early next week as the upper weather pattern changes. The mild weather this past week has been the result of an upper "zonal" flow which brings milder Pacific air across the Prairies while preventing cold Arctic airmasses from advancing south. This pattern will persist over the upcoming weekend but will begin to change to a more amplified "wavy" upper pattern next week which will allow colder air from the Arctic to advance south into southern MB.  The transition to this colder pattern will be marked by some snow Sunday night into Monday with a few cm possible* (see UPDATE below), before northerly winds bring in colder air Monday afternoon into Tuesday.  Temperatures will drop into the minus teens through mid week before some moderation by the end of the week as temperatures rebound back to normal (or even above normal) by mid December.

After that.. there is some uncertainty in how the upper pattern will evolve over Manitoba. The current thinking is that the upper pattern leading up to Christmas will be dominated by an upper ridge over the west coast and  troughing over the Great Lakes/eastern NA.  This would place Manitoba in a northwest upper flow which generally means below normal temperatures here with occasional very cold outbreaks. However, the intensity and duration of these cold snaps will depend on the strength and location of these upper features. At this point, the core of the coldest air is expected over eastern North America which would imply occasional but transitory cold snaps over southern Manitoba modified at times by periodic clipper systems. Until then, get ready for a return to colder weather this upcoming week.

UPDATE (Sun Dec 3):  Storm system will be intensifying overnight through Monday as it tracks across northern Minnesota into NW Ontario. Current guidance indicates the bulk of snow with this system will fall over SE MB into NW Ontario, with Winnipeg and RRV on the western flank of the snow shield. Snowfall from this system will range from 5 cm in the RRV to 10-15 cm closer to the Ontario border overnight through Monday. Increasing winds Monday afternoon into Monday night along with falling temperatures will produce worsening traveling conditions especially south and east of Winnipeg with blowing and drifting snow likely.  

Mild week ahead.. November ending on a mild note after cold start

After a cool weekend, milder weather is set to return to southern Manitoba Monday as another clipper system brings in a shot of warmer air from the west. Temperatures are expected to climb above freezing again across much of southern MB Monday with afternoon temperatures near +3C and up to +7C over snowfree and downslope areas.  Mild weather last Friday eroded a lot of the snowpack over far southern and SW MB, where a lot of bare ground is now becoming exposed even just south of Winnipeg.  This will make it easier for mild temperatures to surface, eroding even more of the snowpack over the next week.   Tuesday will see cooler temperatures return, but will still be near or above normal (normal highs now are -4C)  Temperatures are expected to remain above normal the rest of the week with highs near or above the freezing mark through Friday.  So after a frigid start to November (7th coldest start on record over the first 10 days), the month will end up on a mild note with above normal temperatures likely persisting into the early part of December.

Clipper system brings brief warmup Monday, then getting windy and colder again by evening

A fairly intense clipper system will track through the Interlake area Monday bringing a brief warmup to southern MB as gusty southwest winds push our temperature above the freezing mark (+1C) by afternoon. There could be a band of snow and/or freezing rain ahead of the warm front Monday morning, but accumulations look minimal over southern MB. The bulk of snow will be associated near and north of the clipper system across the northern Interlake and central MB where 10-15 cm is possible. As the system tracks east towards Ontario later in the day, winds will shift into the northwest and increase to 40G60-70 kmh by evening over southern MB, with temperatures falling below freezing along with occasional snowshowers and local blowing snow at times. Road conditions will become slick as the melting conditions of the afternoon quickly freeze up Monday evening. We could see a cm or 2 of snow in the wraparound behind the clipper system before things clear out by Tuesday morning. Colder conditions will return through mid week before a brief moderation again by late week with another clipper system.

Milder week ahead.. but changes loom for late week

After a frigid start to November, the weather pattern is expected to moderate this upcoming week with temperatures more typical of mid November. The first 10 days of the month have averaged -8.8C in Winnipeg, some 7C below normal for the time period, and the 7th coldest start to November since records began in 1872. The past week featured the coldest Nov 9th on record when the temperature fell to -23.7C at Winnipeg airport, with a record low maximum of only -11.4C. This cold start is in sharp contrast to November 2016, which had the warmest start to November on record at +7.0C, an astonishing 16C warmer than this year!

The good news is that temperatures will be a lot more tolerable this week as the persistent Arctic airmass moves off allowing milder air to move in. Conditions look pleasant for the Bombers game Sunday with partly sunny skies and afternoon temperatures near -5C with light winds. Milder temperatures will move in for the new week with temperatures climbing above freezing by Tuesday (high of +2C)  Generally seasonal temperatures are expected through mid week (highs near freezing) before a storm system moves in Friday bringing windy and colder conditions by next weekend.  Until then, enjoy the milder weather this week!  

Get ready folks.. winter arrives this weekend. Snowy Saturday followed by Arctic cold next week

Storm system will spread snow across srn MB Saturday.
10-15 cm is possible along with colder temps behind it

We've had a few tastes of it over the past week or so, but after this weekend, there'll be no doubt about it.. winter will have arrived in Winnipeg and southern MB. A storm system tracking through the Dakotas will spread snow across all of southern MB Friday night into Saturday with a general swath of  5-15 cm possible for many areas including Winnipeg. Winnipeg dodged a bullet Wednesday missing out on an earlier system, but Saturday's system looks more significant and will be harder to miss.  So get ready for a snowy Saturday and poor travelling conditions through the day into Saturday night. And sadly, say goodbye to that bare ground.. this system looks like the start of our winter snowcover that will likely last into next spring! If you haven't done so already, get those snow tires on and get your car winter ready.. or consider postponing travel Saturday if you are not prepared for winter driving yet.

In the wake of Saturday's system, northwest winds will usher in colder air for the new work week, with temperatures some 10C below normal for early November. With fresh snowcover, temperatures will only climb to around -5 to -8C next week, with lows of -15C to possibly -20C! (Average highs right now are +4C, lows of -5C)  Some moderation is possible later next week, but overall, it looks like below normal temperatures will persist well into mid November and likely beyond. This is in sharp contrast to last year when southern MB enjoyed its warmest November on record, with Winnipeg not seeing its first measurable snowfall of the season until Nov 22nd.. the latest start to the snow season ever.  No such luck this year! Winter arrives at least 3 weeks earlier this year.. so get ready!  

UPDATED SNOWFALL TOTALS: 
(source: Env Canada and CoCoRaHS)

Rossburn ........ 23 cm
Roblin ............ 20 cm
Russell............. 19 cm
Woodlands ..... 14 cm
Brandon .......... 13 cm
Neepawa ........ 11 cm
Winnipeg ........ 10 cm
Pinawa .............  9 cm
Steinbach .......... 7 cm
Virden .............. 7 cm
Portage .,..........  6 cm
Emerson ........... 5 cm

Chilly but dry for Halloween.. snow moves in to start off November along with below normal temps

After a blustery and cold Monday with gusty winds and occasional flurries, things will settle down somewhat Tuesday as a ridge of high pressure crosses southern MB. That will give lighter winds much of the day along with generally fair conditions.. so no rain or snow to contend with for Halloween (unlike last year which saw 16 mm of rain.. Winnipeg's wettest Halloween on record). Temperatures will be on the cold side of normal Tuesday, with afternoon highs only near freezing, and evening temperatures of  -2 to -4C. Winds will also be picking up by late afternoon, with brisk southeast winds of 20 to 40 km/h Halloween evening producing wind chills near -10. Bundle up if you're out with the kiddies!

On Wednesday, a clipper system will track through the Dakotas spreading snow across much of southern MB Wednesday into Wednesday night. At this point, it looks like a general 2 to 5 cm is likely with this system, including Winnipeg, with locally higher amounts of 5-10 cm possible in some areas. Below normal temperatures will persist through at least the first week of November behind this system.. a far different story than last year when Winnipeg and southern MB recorded its warmest November on record.  

Fabulous week of October weather ahead!

After the first snowfall season in Winnipeg this past Saturday (2 cm on Oct 14th), the weather will be turning decidedly warmer this week as an upper ridge builds over central North America. This will allow temperatures to rise to well above normal levels this week, especially Tuesday and again Thursday and Friday  (Normal highs this week drop to 10C by mid week)   Monday looks wonderful with sunshine mixing with some morning high clouds and afternoon highs around 16C. Winds will be gusty out of the south in the morning (30-50 km/h) shifting to southwest in the afternoon.  Tuesday is looking even warmer with afternoon highs near 20C along with mainly sunny skies and brisk south winds.  Wednesday will see a bit of a cooldown as a NW flow briefly knocks down the upper ridge bringing in slightly cooler air and highs of 15C. Temperatures however will rebound again for Thursday and Friday as the upper ridge rebuilds, with highs in the low 20s (!) along with gusty south winds.  All in all, a fabulous week ahead after a brief taste of winter this past weekend. Enjoy!          

Nice start to Thanksgiving weekend.. with a cool finish

The weather is looking good for the start of Thanksgiving weekend as a strengthening southerly flow brings above normal temperatures to southern MB on Saturday. Brisk southerly winds gusting to 50 km/h will send temperatures up close to the 20C mark throughout the RRV, including Winnipeg. Conditions are expected to be dry with sunshine giving way to some afternoon cloudiness.  A cold front will cross the region Saturday night bringing cooler conditions Sunday with brisk west winds and highs around 15C. The good news is that conditions should remain rainfree Sunday with a mix of sun and cloud. Another cold front will push through Sunday night bringing cloudy and colder weather Thanksgiving Monday, with highs only around 9C, brisk NW winds and a chance of showers. Whatever the weather, have a safe and enjoyable holiday weekend!    

Welcome rain finally on the way for southern MB..

It's been awhile, but it finally looks like southern MB will have its first decent rainfall in weeks beginning tomorrow and continuing into early Saturday.  Models are indicating a general 20-35 mm of rain for most areas in southern MB Friday into Saturday morning, with locally heavier amounts of 50 mm thanks to embedded thunderstorms firing up over ND later Friday into Friday evening (spreading into southern MB mainly closer to the US border)

As for Winnipeg.. models are all over the place in terms of amounts here, but generally it looks like 25-40 mm of rain is possible from Friday afternoon into Saturday morning, with the bulk of rain falling Friday night when it could be heavy at times. Some models show heavier amounts due to embedded convection moving in Friday evening (GDPS shows over 70 mm for us!) Here are the various model outputs of rainfall for Winnipeg through midday Saturday.. (12Z or 18Z run)

RDPS... 32 mm
GDPS... 72 mm
NAM.... 43 mm
GFS.... 23 mm
ECMWF.. 26 mm
SREF... 18 mm
GEPS... 41 mm 

Multi-model average is 36 mm. Taking out the highest and lowest values gives a mean of 33 mm. Whatever the case, it'll be the most significant rainfall we've had here in weeks! In Winnipeg, only 2 mm of rain has fallen so far this month, coming off its 13 driest August when only 14 mm fell the entire month. Since July 23rd, Winnipeg airport has received only 21 mm of rain, a mere 18% of the normal 119 mm that should have fallen over that time. We are certainly overdue for a good soaking!     

Cool windy end to Labour Day weekend, but summer-like warmth to return by end of week

The last long weekend of the summer season will be ending on a cool and windy note as a strong northwest flow pushes in a  fall-like airmass over Manitoba on Monday, along with a few showers. Highs temperatures will only be in the upper teens, with gusty northwest winds up to 60 or 65 km/h at times. Although we can use the rain, rainfall amounts Monday will be light with only a few mm expected in passing gusty showers. Things will clear up Monday night with better weather Tuesday and Wednesday under a mix of sun and cloud and temperatures in the upper teens to 20C.

The second half of the week is looking wonderful as a southerly flow spreads warmer air back into Manitoba. That should bring sunny and dry weather for Thursday through Sunday, along with increasingly warm and windy conditions with temperatures in the mid to upper 20s. In fact, it's possible much of the RRV will be hitting the 30C mark again next weekend, although it will be accompanied by gusty south winds. So if the onset of cooler weather is getting you down, don't worry.. summer is still not quite done yet!
   

Seasonably warm weather to close out July.. but 30C heat continues to elude Winnipeg

It will be a nice warm week ahead with high temperatures generally in the mid to upper 20s over the RRV and southern MB. Conditions should be generally dry as well with little in the way of showers or thunderstorms expected through Friday. The next threat for organized showers will be on Saturday as a weak frontal system slides through southern MB. The greatest heat through the end of the month however will still be focused out west over SK and AB which have experienced multiple days of 30C or more this month. In Winnipeg, we have yet to hit the 30C mark in July, even though precipitation has been below average and sunshine has been plentiful. The upper pattern this month has brought the bulk of the heat over western Canada with cooler temperatures over eastern Manitoba into Ontario.  There is a chance Winnipeg may be close to the 30C mark by the end of the week. Since 1872, there have been 12 Julys in Winnipeg that have failed to reach the 30C mark, most recently in 2009. With one week to go, we'll see if July 2017 is added to that list.

Coolish Canada Day 150.. but then heat builds for first half of July over Prairies

Happy Canada Day!  Canada is 150 years old today, founded back on July 1st 1867, and celebrations marking the milestone event will be held throughout the country. In southern MB, skies on Canada Day will likely start off cloudy as a disturbance tracks across southwest MB into North Dakota tonight into Saturday. This system will spread a few showers across SW Manitoba tonight and into the Red River valley overnight into Saturday morning. The bulk of showers will likely be mainly south of Winnipeg, but there is the chance the city may see some showers Saturday morning. The system should be out of southern MB by midday leaving a mix of sun and cloud Saturday afternoon along with a northerly breeze of 20 km/h. Temperatures will be on the cool side of normal with highs around 21C, a few degrees shy of the average of 25C for July 1st, but quite comfortable for outdoor activities. There is the chance of some isolated showers popping up Saturday afternoon with daytime heating, but most areas should be rainfree for Canada Day festivities. Skies will be clearing by Saturday evening, with ideal conditions for fireworks at 11 pm.. although a little on the cool side with temperatures near 15C by that time. The rest of the holiday weekend is looking good with sunshine on Sunday and highs of 24C and 27C by Monday under partly sunny skies and increasing southerly winds.  

Pattern change will bring increasing heat over western Canada and Prairies first half of July

Large upper ridge building over western Canada next week
will bring increasing heat over the Prairies, especially west

850 mb temperature anomaly shows core of heat next week
will be over western Canada with highs of 30-35C

A pattern change is expected for the first half of July over western Canada and across the Prairies as a large upper ridge builds over the High Plains and Rockies. This will bring increasing heat over much of the Prairies over the next 1-2 weeks, with a prolonged heat wave possible over Montana, southern AB, and SW Saskatchewan with highs in the mid 30s to possibly 40C in some localities. Look for widespread heat warnings to be issued for much of Alberta and Saskatchewan early next week. Here in southern MB, temperatures won't be quite as hot as out west, but they will climb to above normal values with highs in the upper 20s to low 30s this week, with mid 30s possible near the SK and North Dakota borders. There may be a day or two with thunderstorms as weak fronts pass through southern MB, but overall precipitation is expected to average below normal for the first half of July over much of the Prairies. There is a chance that the upper ridge may build east into southern MB by the second week of July which would bring more intense heat here as well (highs of 35-38C). However, that is still a ways off and we'll have to see how models handle the upper ridge pattern in the days ahead. Regardless, get ready for an extended period of hotter temperatures over the next week or two.. as we get into the climatologically warmest part of the year in southern MB.    

                  

June to end on a cool note..

Temperature outlooks from CPC show favour below normal temperatures
across the Prairies for the next 1-2 weeks at least 

After a nice warm first half of June, the weather pattern has shifted over the Prairies this past week, with the warmest air now suppressed south of the international border. The jet stream has shifted south allowing cooler air from the north to move across the Prairies. And it looks like this pattern will likely persist for the rest of the month into early July. Tomorrow and Tuesday should see a mix of sun and cloud with highs of 18-21C, then a system passing through southern MB will likely bring some showers and thunderstorms Wednesday with highs in the low 20s. Cooler temps will follow for the end of the week, with below normal temps in the teens and scattered showers likely next weekend.  A return to sustained heat in southern MB isn't expected before early July.

Warming trend this week.. dry weather expected into next week

It's been a cool and wet couple of days over southern  Manitoba, but things will be clearing up nicely this week as a stubborn area of low pressure over northern Ontario finally pushes east allowing high pressure to build in from the west. Cloudy skies Tuesday will give way to increasing sunshine by afternoon as the high pressure ridge moves in from Saskatchewan. This will lead to some glorious weather through mid week with plenty of sunshine and temperature in the mid 20s Wednesday and Thursday. The warmer weather will retreat a bit on Friday and Saturday with highs around 20C as we get easterly outflow winds from a cooler high pressure system moving across northern MB into NW Ontario. But things should warm up again by Sunday into next week as we get a return flow of warmer air back into southern MB.

As far as precipitation goes, it looks generally dry through the first week of June with long range guidance showing little in the way of major systems or convection over much of southern MB through the next 7-10 days. There is a risk of some showers and thunderstorms over SW MB Friday, but the risk appears restricted to SW MB into North Dakota. Things are actually getting a bit dry over southern MB, especially over far SW MB which has received only 10-20% of normal rainfall so far this month. Even the RRV has only seen about half the usual rainfall in May (normal May precip is about 55-60 mm) Farmers will be getting increasingly anxious if the dry weather continues for much longer as it will start to affect their newly planted crop.

Oh no! More snow!

It will be back to winter like weather over southern Manitoba Monday as a storm system intensifies over the Dakotas and tracks into northern Minnesota by Monday night. A band of snow is expected to spread into the Winnipeg area by mid morning Monday, with snow intensifying through midday into the afternoon before tapering off Monday evening. Snowfall accumulations will be tricky as some of the snow will be melting on impact, and there will be milder air over southeast MB that will change snow to rain for awhile over parts of southeast MB. For Winnipeg, precipitation should remain as snow with a good 5-10 cm expected by late afternoon, and perhaps 10-13 cm by the time it ends Monday evening if we get under some heavier bands. The best bet for heaviest snow will be towards the Ontario border where 10-20 cm is possible Monday into Monday night.    

UPDATE:  (9:30 am Monday): Latest guidance and radar indicating Winnipeg will be on western edge of this system with bulk of snow mainly east and southeast of the city. Winnipeg will likely still see some wet snow by late morning into this afternoon, but amounts should be minimal with perhaps 2 cm or less on grassy surfaces. Roads will just be wet. Wet snow may even mix with rain here at times today as temperatures stay above freezing. Heavier snow will be confined just to the east and southeast of Winnipeg in places like Steinbach, Whiteshell and Falcon Lake where 5-15 cm of snow is possible through this evening.  

How unusual is heavy snow in late April? 

Although not common, snowstorms are certainly not unheard of in late April or even May in Winnipeg and the Red River valley. Consider these top 10 late season snowfalls (daily) that have occurred in Winnipeg after April 15th. As the table shows, heavy snowfalls have occurred in Winnipeg well into the 3rd week of May.

TOP 10 LARGEST DAILY SNOWFALLS AFTER APRIL 15  
              (WINNIPEG DATA 1872 - 2016)

1.  29.0 cm ............ May 11 2004
2.  21.1 cm ............ May 1 1967
3.  20.8 cm ............ Apr 27 1966
4.  20.3 cm ............ May 19 1931
5.  20.0 cm ............ May 9 2002
6.  17.3 cm ............ Apr 24 1937
7.  16.5 cm ............ Apr 25 1960
8.  15.2 cm ............ May 20 1882
9.  14.0 cm ............ Apr 19 1996
10. 13.0 cm ........... May 5 1938

In 1958, a full fledged blizzard hit Winnipeg on April 28th with 5-10 cm of snow blown by 80-100 km/h winds along with frigid temperatures of -10 to -13C.

Dry April weather continues.. next significant rain threat Friday.

It's been a dry spring so far in southern MB, welcome news for residents in the Red River valley who were looking at potentially major flooding this spring. There has been no measurable precipitation so far in April in Winnipeg and much of the RRV, and this week is also looking dry, until Friday. (There is a slight chance of some light showers Tuesday night, but amounts will not be significant). The next threat of any appreciable rain over the Red River valley will be Friday as a storm system tracks through the Interlake bringing a band of rain across southern MB. Early indications are for rainfall amounts of 5-15 mm with this system, but it's still several days away and there's still a lot of model spread on overall precip amounts. Colder weather will follow in the wake of this system for Easter weekend, with even a chance of snowflurries for Easter Sunday. Long range guidance is indicating the potential for another precipitation bearing system over southern MB for the April 17-19th time period.

March goes out like a lamb in southern MB.. Winnipeg records 7th least snowy March on record

March 2017 will go down in the record books as the 7th least snowy March in Winnipeg in 145 years of records. Only 2.4 cm of snow fell during the month, compared to the "average" of 16.5 cm that usually falls in March. That comes as a relief to residents of the Red River valley after heavy snowfall in December increased fears that a potentially major flood situation would arise in the Red River valley come the spring melt.  A wet fall, soggy soil conditions and a heavy snowpack were leading to an elevated flood risk throughout the valley, contingent on late winter and spring precipitation.

Top 10 least snowy Marches
in Winnipeg

Thankfully, precipitation has been mainly light over the past few weeks in the Red River valley, and a major winter storm that clobbered much of western Manitoba earlier in the month largely spared the valley. Overall, the month of March finished with 14 mm of total precip at YWG airport (17 mm of rain at my site + 2.4 cm of snow) Normal March precipitation is around 24 mm (composed of about 10 mm of rain and 17 cm of snow)  so March precipitation was below normal. Snowfall in February was near normal with only 12.2 cm for the month. In fact, in the 11 weeks since Jan 10th, only 22 cm of snow has fallen in Winnipeg compared to 90 cm in the 6 weeks between Dec 1st and Jan 10th. That has led to a significantly reduced snowpack in the valley, which has gradually disappeared over the past 2-3 weeks.  The reduced snowpack and gradual thaw were ideal conditions to ease the Red River flood threat this spring although mild weather over the past few days has led to some local flooding due to ice jams. The Red River is expected to crest in the Emerson area sometime next week as a "moderate" flood which will gradually progress north over the following days. More major flooding is expected over western MB in the Souris and Assiniboine watersheds where they have had more snow.  

What about April?

So with only 2 cm of snow in March, does this mean winter is over? Well, for the most part.. yes. Now that snowcover has disappeared, it will be easier for the ground to warm up since snowcover acts to reflect heat. But that doesn't mean we won't see any more cold weather or snow. A look at past Aprils in Winnipeg shows that since 1872, only 8 Aprils have not seen ANY snow during the month (not even a trace). 95% of Aprils have seen at least a trace of snow, and more than half (56%) have seen at least 5 cm of snow. So although snow is currently not in the forecast, it would be highly unusual to go the entire month of April without seeing at least some snowflakes at some point. Hopefully, April 2017 is one of those months with little or no snow. 

Chart showing odds of snow in Winnipeg during April 

April snowfall stats for Winnipeg:

- Normal April snowfall: 10 cm (but highly variable year to year) 

- Normal days in April with measureable snow (>= 0.2 cm): 3
- Odds of at least 1 day in April with a snowfall >= 2 cm: 67% (2 out of 3 years)
- Odds of at least 1 day in April with a snowfall >= 5 cm: 41% (2 out of 5 years)
- Odds of at least 1 day in April with a snowfall >= 10 cm: 17% (once every 6 years)

- Snowiest April on record: April 1997, 48.6 cm (year of the big flood)     

- least snow in April:  0.0 cm (8 years;  last occurrence was April 1998)

Graph of April snowfall in Winnipeg shows how variable it is year to year.
Snowy Aprils are just as likely as snowfree ones in any given year
(graph from @jjcwpg) 

Historic winter storm slams Manitoba March 6-10th .. Winnipeg and RRV escape worst of storm

The strongest winter storm in at least 20 years slammed Manitoba during the week of March 6th to March 10th, bringing widespread snow, high winds, and blizzard conditions to much of the province. The storm system, which originated in the western US on Sunday March 5th, crossed into North Dakota on the 6th and then tracked north across the Red River valley, with the center of the low tracking right over Winnipeg Monday evening March 6th with a deep central pressure of 978.7 mb, just 0.1 mb off the lowest pressure ever recorded in the city in the month of March. The storm then continued to intensify and track north, moving over Lake Winnipeg and then into northwest Ontario, where it would deepen to an incredible 964 mb near Big Trout Lake by Tuesday afternoon March 7th. Such a low pressure is rare for this part of the world, and is associated with only the most intense storms. And what an intense storm this was!

The massive storm brought prolonged blizzard conditions to western Manitoba March 6-7th, with powerful northwest winds gusting up to 90 km/h at times producing extensive whiteout conditions with severe blowing and drifting snow. Brandon recorded 31 straight hours of blizzard conditions beginning Monday evening before tapering off around midnight Tuesday night.  Officially, Brandon Airport reported 41 cm of snow during the 2 day blizzard, but accurate measurements were difficult due to the severe blowing and drifting  snow. The prolonged high winds led to massive drifting across Westman, with reports of 12-15 foot drifts south of Brandon that buried vehicles and structures.

The severe winter storm of March 6-7th left massive drifts across
western MB. This scene is from Crystal City area near the US border.

As the vicious storm headed north towards Hudson Bay Tuesday, it set its sights on northern Manitoba and pummelled the north with one of the worst winter storms on record there.  Churchill was particularly hard hit being exposed to 3 days of severe blizzard conditions from March 8th to 10th.. including zero visibility for 2 full days. The town was stranded for 2-3 weeks due to blocked rail lines that could not get supplies to the town. Some 40-70 cm of snow was reported in the north including 67 cm in Lynn Lake and around 60 cm in Thompson.        

Milder weekend ahead.. winter storm system looms for Monday

After a cold start to March, things will be turning milder this weekend as a southerly flow flushes out the Arctic airmass currently over the eastern Prairies. In Winnipeg, temperatures are expected to climb to the freezing mark on Saturday and +2C on Sunday. Note however that Saturday will see gusty south winds gusting 60-70 km/h, so that high of 0C will feel a lot colder. Sunday looks a lot more pleasant with lighter winds and temperatures above freezing.

12Z NAM model valid Monday afternoon shows
rain over SE MB and snow west

Attention then turns to a potential winter storm system that will be impacting southern Manitoba Monday into Tuesday. At this time, models are indicating the development of a storm system over the western United States Sunday that will track across the Dakotas Monday and intensify as it moves into NW Ontario by Monday night. This system will likely start off with some rain or freezing rain over the RRV and SE Manitoba with snow over western MB and he Interlake regions. As the storm pushes towards the Ontario border later Monday, strong northwest winds on the backside of the system will draw in colder air and spread snow and blowing snow across the remainder of southern Manitoba Monday afternoon into Monday night. Travel conditions could become hazardous across southern MB through the day Monday into Monday night, especially with falling temperatures and increasing winds that will freeze up any standing water from leftover rain or melted snow.

12Z GDPS model valid Monday evening shows
intensifying storm over Lake of the Woods 

There's still a lot of uncertainty on the track of this system and the timing when precipitation will change over to snow which will impact overall snow totals.  A track across southeast MB would push the heaviest snow over western Manitoba through the Interlake regions (possibly 15-25 cm) with lesser amounts (5-10 cm) over the RRV and SE MB.  A track through Lake of the Woods or east would bring heavier snow over the southern Interlake and RRV. We'll continue to monitor trends over the next few days to get a better idea of how this storm will track, and what impacts it will have for southern MB. In the meantime, be prepared for a potential return of wintery conditions Monday into Tuesday. Stay tuned..

Thaw coming to an end.. colder weather on the way

After another mid winter mild spell that featured thawing temperatures and rain, things will be cooling off this week as a colder airmass spreads over western Canada. Preceding the cooldown will be a fast moving clipper system that may bring a coating of snow (Tr - 3 cm) Tuesday night into early Wednesday across Winnipeg/srn MB.  Temperatures will be dropping behind the system for Thursday into the weekend, with temperatures more seasonable for late February (normal high -7, low -17C)  That will be good news for outdoor enthusiasts and winter events such as the Festival du Voyageur which has had to cancel several outdoor events due to the mild springlike weather. In addition, no major storm systems are expected through early next week over southern MB, so the colder weather should also be accompanied by dry and mainly sunny conditions. Good opportunity to finally wash that car again!  

Rob's Obs website URL changing..

Please note that as of March 6 2017, Shaw will be retiring their members.shaw.ca web hosting services, which hosts my Rob's Obs website.  As a result, the URL for my Rob's Obs website (http://members.shaw.ca/mainweb/robsobs/robs/home.htm) and all related webpages will no longer be valid after that date. Over the next couple of weeks, I will be moving my website and webpages over to a server hosted by A Weather Moment.   

The new URL for my main Rob's Obs website will be
http://aweathermoment.com/robs-obs/robsobs/robs/home.htm    

I hope to have most of my webpages moved over to the Weather Moment server by March 6th. Note also that my www.robsobs.ca URL will be mirrored over to the the above URL as of that date as well.  Please update your bookmarks to the above URL if you would like to continue to access my site. Thank you.

(Of course, you can always google Rob's Obs anytime to find it the site as well)    

January thaw melts records in Winnipeg

It was a record breaking mild weekend in Winnipeg as an unprecedented stretch of above freezing temperatures turned ice rinks and streets into puddles and slush across the city. The temperature at Winnipeg airport (where official temperatures are measured) rose above freezing at 4 am Friday morning Jan 20th, and stayed above freezing until 11 pm Sunday evening Jan 22nd. The stretch of 67 straight hours above freezing set a new record for the longest January thaw on record in Winnipeg, eclipsing the old mark of 44 straight hours Jan 8-9th 2002.     

Hourly temperature records for Winnipeg airport go back to 1953, but even looking at daily records shows that the 67 hour thaw is likely the longest such stretch in January in Winnipeg since records began in 1873. The only other comparable January thaw* would have been Jan 9 - 12 1928 when the temperature failed to drop below -1.6C over the 4 day period. However even then, there wasn't a 48 hour period where the temperature was consistently above 0C, so it appears this most recent warm spell is the longest such streak for January in Winnipeg in 144 years of weather records.  (*NOTE: "January thaw" in this case is defined by consecutive hourly temperatures of 0.0C or more. There have been longer stretches in January where daily high temperatures have reached 0.0C or higher, but temperatures dropped below freezing at night. The longest stretch with daily highs of 0.0C or more in Winnipeg in January was 9 straight days in January 1942 from the 16-24th, with 14 in total during the month, including Winnipeg's all time January high of +7.8C on the 23rd)  

The 3 day thaw also set new daily record high minimum temperatures in Winnipeg from Jan 20 to 22nd inclusive:

Record daily minimum temperatures set Jan 20-22 2017
(table courtesy of @jjcwpg)

Normal lows for this time of year are near -23C, so these temperatures are almost 25C above normal lows! The low of +0.9C on Jan 21st was only the third time in 144 years where the temperature did not drop below freezing during a January day in Winnipeg. The only other dates were Jan 12 1928 (minimum of +1.1C), and Jan 14 1894 (minimum of 0.0C).  Thus, a 67 hour streak of above freezing temperatures in January in Winnipeg is an exceedingly rare occurrence. Note also that 2.9 mm of rain fell on Jan 20th, the 2nd highest rainfall for any January day or month since 1873 (second only to the 3.8 mm that fell on Jan 20 1944) The mild weather, although welcome after a frigid first half of January, forced the closure of city rinks and skating trails as ice melted into slush and giant puddles. The thaw also resulted in locally slippery streets and walkways as water slicked up packed snow and ice.   

Temperatures are slowly cooling off this week to below freezing, but will remain above normal values the rest of the week before more seasonable temperatures return by the weekend.   

A nice warmup beginning this weekend after frigid week..

Mother Nature is finally relenting.. but not after giving southern Manitoba a  parting shot of Arctic like weather this past week including blinding blizzard conditions Thursday, then bone-chilling frigid cold Friday with windchills of -40 to -45.  The good news is that the worst of the bitter cold is over.. for at least a week anyways.. as a milder Pacific flow sets up over the Prairies this week, pushing out Arctic air that has been entrenched over southern Manitoba much of the month.  Today will see temperatures near the normal high of -13C, and with sunshine and light winds, it will feel some 20 degrees warmer than Friday. Sunday is looking even better as temperatures finally climb into the minus single digits for the first time since Jan 1st. The rest of the week is looking wonderful.. dry and mild with temperatures well above normal reaching the freezing mark by mid week, then a January thaw likely by the end of the week as temperatures climb to +1 to +3C over the Red River valley. This will be welcome news for winter weary Manitobans who have had endure 2 straight weeks of cold and snow, icy roads and general cabin fever.  The good news is that the warmup will not be accompanied by any major weather systems this week, so the week is not only looking mild, but precipitation free as well!  The next system that poses a threat for precipitation over the RRV will be next weekend (Jan 21st-22nd) with some possible snow, rain or freezing rain moving into southern MB. Until then .. time to finally get back outside and enjoy the outdoors. Let the warmup begin!

Yet another winter storm to bring more snow to southern MB.. mainly south and east of Winnipeg

Another storm system is getting organized in the American midwest and will be tracking into Minnesota by Tuesday bringing another round of snow to southern Manitoba to begin the new year. Snow from this system is expected to spread into southern Manitoba during Monday, and become heavier Monday night into early Tuesday before tapering off. Snowfall amounts will range from about 5-10 cm in the Winnipeg area to 20 cm over the southern RRV into SE Manitoba by Tuesday evening.  This system is not expected to be as intense as the Christmas Day/Boxing day storm which brought heavy snow and blizzard conditions to much of southern Manitoba including Winnipeg. However, snow and increasing winds will make for difficult travel conditions later Monday through Monday night into Tuesday morning especially over southern RRV and SE MB. Heavier snow of 20-30 cm is possible south of the US border in northern ND and northern Minnesota as well as NW Ontario.  Be prepared for poor travel conditions and possible roads closures if you plan on travelling south or east of Winnipeg Monday into Tuesday.

Snowfall amounts (in inches) forecast by NAM model through
Tuesday evening. Heaviest amounts expected S and E of Winnipeg  

This system comes on the heels of the snowiest calendar month in Winnipeg in almost 60 years. Winnipeg saw 68.8 cm of snow in December, 3 times the normal snowfall for December (23 cm) and the snowiest month in the city since Nov 1958 when 77 cm of snow fell.  The snowfall has wiped out the city's snow clearing budget, which was at a surplus heading into December given last year's tame winter and this year's mild fall. The city ended up spending $39 million on street clearing operations in December, $11 million more than budgeted.