Elsewhere in Weather News: January 4th, 2014

Snowstorm Sweeps across Northeast US, Cold Temperatures Follow

A powerful low off the Atlantic coast impacted the Northeast US this past Thursday/Friday bringing heavy snow to the region and blizzard-like conditions. Blizzard warnings were issued for Cape Cod and surrounding regions as winds howled around 70km/h and heavy snow fell. Conditions did improve snow-wise late Friday, but very cold Arctic air ushered in behind the low was of concern. In total, about 4,500 flights were cancelled out of New York alone, causing problems for holiday travelers. Schools and most government offices were closed in Washington DC on Friday due to the adverse weather conditions. Boxford, Mass appeared to be hardest hit with snowfall totals around 60cm, however, Boston was not far behind with 45cm followed by New York’s 25cm. On Friday night 16 deaths had been reported to be associated with the storm.

Temperatures are expected to rebound and warm up for the Northeast as another low pressure system approaches, from the west. It will draw in some warm air; highs Sunday (overnight) are even expected to rise in the (positive) double digits making for a 30°C temperature swing in less than 48 hours for parts of the Northeast.


Arctic air infiltrates across the Northern Plains, US Midwest behind the low centered in southern Quebec. Valid Monday morning. (Source: Twisterdata)
Arctic air infiltrates across the Northern Plains, US Midwest behind the low centered in southern Quebec. Valid Monday morning. (Source: Twisterdata)

Some potentially record-breaking low temperatures are expected on the horizon for the Midwest behind this system though, as the polar vortex pivots all the way down to the Midwest. On Friday the Governor of Minnesota had already cancelled schools state-wide on Monday in preparation for this next potent blast of Arctic air that will make its way east.

Another Day of Record Highs, Then…Winter.

Winnipeg has enjoyed 32 consecutive days with above average temperatures, making this one of the more pleasant winters in recent memory. This is about to abruptly change as winter is making an ungraceful return tonight. Before that, however, is another beautiful day with a good chance that more daytime temperature high records will be broken.

2012-01-10 21Z Surface Prog.

Jan. 10, 2012: 21Z (3PM) surface prognosis from the GEM-REG. Blue line represents cold front, red line represents the warm front.

This afternoon will bring more record-setting temperatures to southern Manitoba as the area is drenched in one last shot of Pacific air. By mid-afternoon, Winnipeg will be firmly in the warm sector, and with 850mb temperatures of 2 or 3°C, temperatures should reach as high as 6 or 7°C through a majority of the RRV, Winnipeg included. There is a slight chance that some areas close to the western escarpment of the RRV could see another day of 9 or 10°C with the extra push from downslope winds and their continued lack of snow cover. That being said, I fully expect daytime high records to be broken in many communities in the RRV today.

Tonight, however, is a whole different story.

Winter Returns

After being held well to our north for over 4 weeks, Arctic air will surge across the Prairies today and tonight, bringing a drastic change to the weather. The cold front will sweep through Winnipeg between 00Z and 03Z (6PM & 9PM, respectively), ushering strong northwest winds and much colder air. Much of the southern Prairies will see snowfall with this system, with areas closer to the international border receiving 2-4cm. Winnipeg will be near the northern fringe of the snowfall, but I think that we’ll see at least 2cm of snow here. I think that 5cm is very unlikely, but there is still some uncertainty in how intense the band of snow will be. The most significant snowfalls will occur through the Northern Interlake, where they’ll be under the influence of a hang-back trough from the main low pressure system, bringing them snow for a longer period of time than us in the southern portions of the province.

2012-01-11 15Z 850 Wind Prog

Jan. 11, 2012: 15Z (9AM) 850 wind prognosis from the NAM

With winds at 850mb forecast to be 30-40kt, surface winds have the potential to gust as high as 70km/h overnight. Likely, we’ll see a period of sustained winds near 50km/h before things settle out with sustained winds near 40km/h with gusts to 60km/h. Combined with temperatures that should fall to near -15°C tomorrow morning, wind chill values will be as low as -25 overnight.

2012-01-12 06Z 850 Temp Prog

Jan. 12, 2012: 06Z (Midnight) 850mb temperature prognosis from the NAM

A second cold front will pass through the RRV between 15Z and 18Z tomorrow morning (9AM and Noon), reinforcing the strong winds and causing temperatures to either remain steady or drop through the afternoon. The gusty northwest winds should continue through the whole day, with some light flurries and temperatures that will start near -15°C and drop to close to -20°C by evening. These temperatures combined with the wind should result in wind chill values near -30 for most of the day.

Normal daytime highs for this time of year are around -13°C and normal overnight lows are around -24°C. For the first time in over a month, Winnipeg will experience below-normal temperatures.

Extremely cold air at 850mb will move over the southern portion of the province Wednesday night; with 850mb temperatures in the -25 to -30°C range, we can expect overnight lows close to -25°C for Wednesday and Thursday night, with a daytime high on Thursday barely above -20°C. The GEM-REG is a little warmer than the NAM on the cold air moving over the RRV, so there is a chance of temperatures being a couple degrees warmer than this, but I’ll always bet on the cold air.

Fortunately, it looks like the cold weather will be relatively short lived. Current indications are that another low tracking across the Prairies should push warmer air into Winnipeg for the weekend, with daytime highs near -5°C. More on that later in the week.


UPDATE: 6 records fell again today across Manitoba as most places enjoyed yet another mild day.
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LocationNew
Record
Old
Record
Old Record
Year
Fisher Branch4.92.42002
Gimli4.73.01990
Gretna7.52.62006
Melita4.32.52002
Pinawa6.53.51990
Winnipeg (Tie)5.15.11990

Potentially Record-Breaking Warmth on the Way!

Warmer weather is on the way for Winnipeg this week as another surge of mild pacific air crosses the Prairies. Temperatures will push well past 0°C on Thursday, with several record highs at risk of being broken across Southern Manitoba.

00Z Fri. SFC Temperature from GEMGLB

Surface Temperature plot valid for 00Z, Friday January 6th, 2012

Warm air will surge across the Prairies with a low pressure system that will track across the Central/Northern Prairies Wednesday/Thursday. Those of us in the Southern Prairies will get to enjoy a nice early-January day where temperatures will reach between 5°C and 10°C by Thursday afternoon with relatively light winds.

Temperatures should be restricted by the snow cover, and I’d like to see a solidly southwest wind to get daytime highs as high as currently forecast (+7°C for Winnipeg).

Thursday, January 5, 2012 18Z Wind Field from GEM-GLB

Surface Wind & MSLP for Thursday, January 05 valid at 18Z from the January 3rd, 2012 12Z run of the GEM-GLB.

Currently, winds are forecast to shift from southerly to westerly in the afternoon, however if the troughing ahead of the low is not as deep as currently forecast, southerly winds could prevail in the RRV and keep our temperature significantly lower. That being said, I’d be willing to pin the daytime high for Winnipeg to be about 6°C, reached late in the afternoon. This temperature is well above the -16°C it reached last year on January 5th, the -13.5°C on January 5th, 2010, and the -24°C it reached on January 5th 2009.

The average daytime high temperature for January in Winnipeg is -12.7°C, and the warmest temperature on record for any day in January in Winnipeg is 7.8°C, set on January 23, 1942. The current record high for January 5th is 4.3°C, set in 1984. We will definitely be well above our average daytime high on Thursday and most likely break the old daily record. Is it enough to break the all-time temperature record for January in Winnipeg? Let us know what you think in the comments!

Miserable Weather on Tap

Don’t let the bits of sun and relatively warm temperatures fool you; tonight is going to be downright awful.

A complex double-barreled low pressure system (a term used when two separate lows are moving together as one entity) is moving out of Saskatchewan and Montana into Southern Manitoba this morning.  This system has brought a mix of precipitation into Southern Manitoba this morning, including freezing rain over western areas and heavy snow in the Interlake.  Numerous warnings have been issued across the region for weather happening now or expected to happen this evening.

The risk of freezing rain will persist through much of Southern Manitoba for an hour or two longer before temperatures will be warm enough that any precipitation will simply fall as rain.  Even though little precipitation has fallen over the Red River Valley this morning, Manitoba Highways is reporting that many sections of Highway 75 and Highway 1 heading west of Winnipeg are partly iced cover due to the slight melt and re-freeze yesterday afternoon.  As temperatures will just barely get over 0°C today, there may be portions of highways that are still quite slippery throughout the day.

Tonight
Perhaps the biggest impact from this storm will occur tonight over the Red River Valley.  As the low passes to the east, cold air will plummet down the backside of the system through the RRV.

 
24hr Accumulated QPF valid 12Z Saturday March 12, from the 00Z run of the GEM-LAM REG Model 

As the system passes, an intense band of wrap-around precipitation will move into the RRV, bringing heavy snow to Winnipeg by 6 or 7PM tonight.  Along with this heavy snow, this system will bring significant winds as well.


Surface Winds valid 06Z Saturday March 12, from the 06Z run of the GEM-LAM REG Model 

Sustained winds of 50-60 km/h with gusts potentially as high as 90 km/h will blast cold air into the RRV, which will plummet the temperature from 0°C or +1°C down to approximately -14°C or -15°C over the span of a few hours.  This will rapidly freeze any standing water which will very likely create extremely slick roads tonight.  And last but not least, these winds, combined with the heavy snow, will very likely produce blizzard conditions through a good portion of the night.

The weather conditions will deteriorate extremely quickly this evening to become a significant winter storm.  Anyone who has plans to travel in the Red River Valley tonight should keep updated on warnings, forecasts (or for a smartphone), the RADAR, and highway conditions to be able to make safe, educated travel plans.  Good satellite imagery to track this system can be found here at the U of M.