Monday, December 30, 2013

Coldest December temperature in 80 years possible Tuesday morning as 2013 ends with brutal cold spell

Low temperatures from the
RGEM model valid Tuesday
morning Dec 31 2013.
Note pockets of -40C temps
across southern MB. 
Baby it's cold outside.. even for hearty Winnipeggers.  2013 is ending with a brutal cold spell with temperatures some 10-15C below normal for the end of December. Winnipeg has hit lows of -35C the past two mornings, with highs only in the minus 20s. And the worst is yet to come as the peak of the cold spell moves in by tonight. Today will be bitterly cold with highs barely nudging above the -30C mark. Luckily winds will be light to offset the frigid temperatures somewhat. Tonight however with clear skies and a light northwest wind, temperatures will plummet towards the -40C mark by Tuesday morning, and -50 with the windchill.. dangerous cold that can lead to frostbite within minutes, or deadly hypothermia if exposed to the cold for a prolonged period without proper clothing. If Winnipeg hits -40C early Tuesday, it would mark the first time the city has hit the -40C mark in almost 7 years (a low of -41.7C on Feb 5 2007)  It would also mark the first time in 80 years that Winnipeg has hit the -40C mark in December, a feat last achieved on Dec 28 1933 with a temperature of -41.1C. This shows how unseasonably early this cold snap has been, with similar cold spells more typical here in January or February.  The cold weather is expected to persist though New Years Day and Thursday, before another Alberta clipper brings in snow and moderating temperatures Friday. The respite however will be short lived as we get back into below normal temperatures again next weekend into next week. Bundle up and stay warm folks!  Bitter cold is here for awhile!

UPDATE Dec 31: Official low at YWG airport was -37.9C this morning, which makes it the coldest December temperature in Winnipeg since 1933.  The -37.9C low this morning just edges past the -37.8C readings recorded on Dec 31 1967 and Dec 31 1973. It was not a record low for the day however, which still stands at -38.3C on Dec 31 1884.  (Click here for list of daily December temperature records for Winnipeg since 1872)

Thursday, December 26, 2013

Mild end to the week.. then snow Friday night into Saturday heralds arrival of another deep freeze to cap off frigid December

Forecast snowfall amounts from
GEM model through Saturday
showing swath of 10+ cm across
southern Manitoba 
The week will be ending on a mild note across southern MB as temperatures climb towards the freezing mark Friday thanks to a westerly flow of mild Pacific air spreading in from Alberta. The mild temperatures however will be nothing more than a brief tease from Mother Nature, as another blast of Arctic air moves in over the weekend into next week. The deep freeze will be ushered in by a clipper system from Alberta which will track east and spread snow across southern Manitoba Friday night into Saturday morning, with 5-10 cm possible across Winnipeg and the Red River valley and 10-15 cm across the western parklands.  The snow will be accompanied by brisk northerly winds gusting to 50 km/h which will send temperatures tumbling into the minus twenties Saturday, along with blowing and drifting snow and wind chills approaching minus 40.. a shocking change from the pleasant conditions Friday.  Bitterly cold temperatures will prevail Sunday through New Year's Day with highs only in the minus 20s and lows in the minus 30s, capping off what will be the coldest December in Winnipeg since at least 2000. So enjoy the next couple of days.. another Arctic blast is on the way!          

December 2013 is running some
7C below normal across
southern Manitoba and
northern Plain states  
How cold has it been this December in Winnipeg? Through Christmas, the average temperature this month has been -20.2C, or about 7C below the normal December average (-13.5C, 1981-2010 average). Since December 4th, only 2 days have been above normal this month, with another frigid spell forecast to end the month. This will likely end up being the coldest December in Winnipeg since at least 2000, when Winnipeg recorded a December mean of -22.0C, its 4th coldest December on record (since 1872)  The coldest December on record in Winnipeg was way back in 1879 with a bone chilling mean of -26.0C for the month. That month also featured the coldest temperature ever recorded in Winnipeg with a -47.8C reading on December 24th. 

Monday, December 23, 2013

Snow and strong winds moving in overnight into Christmas Eve morning.. quiet weather expected for Christmas

A band of snow over western Saskatchewan this evening is forecast to track east into southern Manitoba tonight reaching Winnipeg and the Red River valley overnight into the morning rush hour. Not a lot of snow is expected in Winnipeg.. perhaps 2 cm or so.. but strong southerly winds gusting to 60 or 70 km/h will produce considerable drifting and blowing snow, with poor visibilties likely in open areas. This area of snow is expected to move off by midday Tuesday, with diminishing winds and milder conditions for the afternoon. Seasonably cold weather is expected through the Christmas holidays with no major snowfalls.. good news for travellers.. before our next chance for more significant snow by Saturday as a clipper system moves into southern MB. Whatever the weather.. have a safe and happy holiday season. Season's greetings from Rob's Obs!

Sunday, December 15, 2013

After coldest December temperature in Winnipeg in 40 years.. a big, but temporary, warm-up on the way Monday..

Minimum temperatures (C)
Sunday Dec 15 2013
Record lows over much of MB
An arctic ridge of high pressure sprawled across Manitoba Saturday night brought some record cold temperatures early Sunday with temperatures plummeting to the -35 to -40C range over southern Manitoba, and -43C in Thompson. In Winnipeg, the thermometer at Winnipeg airport bottomed out at -37.3C Sunday morning, setting a new record low for Dec 15th, eclipsing the previous record of -37.2C set way back in 1879. (records began in 1872) For Winnipeg, it was the coldest December reading in 40 years, since a -37.8C reading on December 31 1973. That -37.8C reading, tied on Dec 31 1967, stand as the coldest temperatures ever recorded at Winnipeg airport in the month of December since records began there in 1938. However, previous to 1938, much colder temperatures have been recorded in Winnipeg in December at the former weather observing site at St John's College which took weather observations from 1872 to 1938. This included Winnipeg's all time coldest temperature during a remarkable cold snap in December 1879 that saw the temperature plummet to a record low of -47.8C on Dec 24 1879. The high that day was only -39.4C, making it the coldest day in Winnipeg history since records began in 1872.  By the way, the last time a reading of -40C or lower was recorded in December in Winnipeg was December 28 1933 with a low of -41.1C.

Coldest December temperatures in Winnipeg over the past 50 years  (since 1963)

Dec 31 1973 ............. -37.8C
Dec 31 1967 ............. -37.8C
Dec 15 2013 ............. -37.3C
Dec  24 1996 ............ -37.0C
Dec 12 1995 ............. -37.0C
Dec 20 1989 ............. -37.0C 

But enough about the cold.

Temperature map valid 1 pm Sunday Dec 15th 2013
Note large wave of mild air over western Canada
poised to spread east over the next 24 hours 
The frigid cold snap which has been locked over Manitoba for the past 10 days, will finally break Monday as a warm front from western Canada moves east and spreads a westerly flow of milder Pacific air across southern Manitoba. This will allow temperatures in Winnipeg to climb into the minus single digits Monday afternoon for the first time in two weeks. Note however, that in advance of the warmup, a band of snow ahead of the warm front will push into Winnipeg and the Red River valley by late Sunday afternoon giving a few hours of snow through the evening. 2-4 cm is possible along with reduced visibilities in blowing snow as southerly winds increase through the evening.

The milder weather is expected to last into Tuesday, but unfortunately it doesn't look like this will be a sustained warmup. Another clipper is expected by midweek with more snow (possibly another 2 to 5 cm), followed by a reinforcing shot of Arctic air by the end of the week into next weekend that will send temperatures back well below normal over southern Manitoba through the Christmas holidays. So enjoy the next couple of days of relief while you can!

Temperature trace from Rob's Obs weather station
Charleswood, Winnipeg - Dec 16 2013
showing dramatic temp rise from Sunday morning
UPDATE: Dec 16 2013
Temperature rises to -1.9C at YWG airport Monday afternoon, a phenomenal rise of over 35C within 30 hours from Sunday morning's low of -37.3C. The graph left shows the dramatic temperature rise as measured at my backyard weather station in SW Winnipeg. Note the steeper temperature rise around noon when winds shifted into the west and tapped the mild Pacific airmass.

Friday, December 06, 2013

Deep freeze settles in after mid week snowstorm..

CPC 6-10 day outlook does
not look promising for those
looking for mild weather 
The storm system that dropped 15 to 25 cm of snow across the Red River valley and southeastern MB Tuesday into Wednesday has long since moved out of the region, but in its wake, frigid Arctic air is flooding into southern MB as a massive Arctic ridge pushes in from the west.  The core of the coldest air is found over Alberta and western Saskatchewan today where temperatures have struggled to get much above the -30C mark this afternoon. This ridge will build into North Dakota over the weekend, maintaining its icy grip over the Prairies. Temperatures in Winnipeg are expected to stay at or below the -20C mark through much of next week, with overnight lows approaching the -30C mark. West to southwest winds of 20 km/h will produce windchills in the minus -30s during the day, and close to -40 at night. Temperatures are expected to moderate a bit for the end of next week as a weak system crosses southern MB, however below normal temperatures are likely to continue for the foreseeable future. Bundle up and hunker down! Mid winter cold has come to town!    

Tuesday, December 03, 2013

Driving conditions to worsen Wednesday into Thursday as storm system brings snow and increasing winds to southern MB..

Model ensemble snowfall totals
forecast through Thu morning (cm)
15-20 cm possible over RRV
and SE MB
The storm system that will be tracking across the Dakotas through Minnesota will be spreading snow across southern MB overnight through Wednesday, along with increasing northerly winds as the system intensifies to our southeast. Although the heaviest amounts of snow are expected mainly across northern Minnesota into NW Ontario with this system, it looks like southeastern MB and the Red River valley will still be getting a good amount of snow on the northwestern flank of the storm. Light snow this evening will pick up overnight with about 2-4 cm expected by the Wednesday morning commute. Snow will continue all day Wednesday into Wednesday night becoming moderate at times. Another 10 cm of snow is expected in the Winnipeg area by Thursday morning with up to 15 cm over areas to our south and east.  Snow will finally taper Thursday but not before storm totals of 10-20 cm over the RRV and SE Manitoba. In addition to the snow, northerly winds will be steadily increasing Wednesday as the storm intensifies, with gusts to 50 or 60 km/h likely by afternoon and evening.  This will lead to extensive blowing and drifting snow with poor visibilities becoming more frequent by evening especially in open areas. As a result, driving conditions will steadily worsen Wednesday into Wednesday night, so allow a lot of time if you plan on travelling. The snowfall will be winding up Thursday, but gusty winds and cold temperatures will continue to produce poor driving conditions especially Thursday morning. Allow plenty of time for commuting and getting to your destination over the next couple of days as this next bout of wintery weather hits southern MB.  

Environment Canada has issued a special weather statement for southern MB concerning this storm system, with winter storm warnings in effect across North Dakota and northern Minnesota.

Monday, December 02, 2013

Storm system taking track further south.. less snow now expected for southern MB

Storm snowfall forecast through
Wednesday night.
Highest amounts expected
south of US border
The winter storm that has been pounding Alberta and southwest Saskatchewan will be heading east over the next day or two, but is now expected to impact areas mainly south of the international border. As a result, southern MB will be seeing less snowfall Tuesday through Wednesday as the storm tracks through the Dakotas. It now looks like areas along and south of the Transcanada highway will be seeing about 5 to 10 cm of snow through Wednesday with the highest amounts near the International border. Heavier snowfall is expected across North Dakota and Minnesota where winter storm watches and warnings are in effect, in anticipation of 15 to 25 cm of snow along with increasing winds and poor visibilities in snow and blowing snow. In the wake of the storm system, colder weather will be flooding into southern Manitoba with temperatures in the minus 20s for the end of the week through the weekend.

Sunday, December 01, 2013

Winter storm gaining strength over western Canada.. impacts to spread over southern Manitoba Monday through Wednesday..

Winter storm and blizzard warnings
cover much of western Canada
Sunday evening
A major winter storm is gaining strength over the Canadian Rockies this evening.. and this storm will be spreading its wintery impacts across the southern Prairies into southern Manitoba over the next few days. Winter storm and blizzard warnings are out for much of Alberta and southern Saskatchewan as the storm intensifies tonight into Monday bringing snow, increasing northerly winds and falling temperatures across the western Prairies. The first wave of snow from this system is expected to spread over southern Manitoba Monday with a few cm possible especially over SW Manitoba where 5-10 cm is possible.  The storm is forecast to track across Montana and through the Dakotas spreading another wave of snow across southern Manitoba Monday night through Tuesday into Wednesday. There remains considerable uncertainty as to how intense this storm system will be by the time it reaches southern Manitoba by Tuesday. Some models are suggesting the storm will re-intensify over the Dakotas bringing significant snow and possible blizzard conditions to southern MB and the Red River valley Tuesday into Wednesday. Other guidance shows the storm tracking mainly south of the border with minimal impact over Winnipeg and the northern Red River valley. At this point, it's best to be prepared for a possible significant snowfall event Tuesday into Wednesday across southern MB, especially over SW Manitoba and the southern Red River valley with areas of blowing and drifting snow increasing by Wednesday. More details will become clearer as the storm evolves over the next 24 hours. Note that winter storm watches are now in effect across all of North Dakota and northern Minnesota in advance of this system, so be prepared for adverse winter weather if you have any travel plans to the west and south of Winnipeg over the next couple of days.

Keep track of weather conditions across southern Prairies and North Dakota via webcams from Rob's Obs webcam page.