Monday, January 23, 2017

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.   

Saturday, January 14, 2017

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!

Sunday, January 01, 2017

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.