After a brutally cold weekend that saw temperatures drop to the minus 30C mark and windchills of -40 or lower, southern MB awoke to a different world this morning as temperatures soared into the minus single digits by 8 am.. a difference of +25C from 24 hours earlier. In Winnipeg, the temperature at 8 am was -4C, after being -30C at 8 am Sunday, the 18th greatest temperature rise within 24 hours in Winnipeg since 1953. Southwest winds ushered in a milder Pacific airmass over southern Manitoba overnight, flushing out the Arctic air that had been entrenched over the area since Dec 9th. And the good news is the above normal temperatures should continue the rest of the week, allowing for a pleasant lead up to the Christmas holidays. A couple of fast moving clipper systems will bring an occasional coating of snow (2-4 cm) both today and Wednesday, but overall, no major system are expected to impact southern Manitoba this week.
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| Greatest temperature rises within 24 hrs in Winnipeg since 1953 Data courtesy of @jjcwpg |
Potential winter storm for Christmas Day/Boxing Day?
The benign weather pattern may come to end over the Christmas holiday weekend as long range models are indicating the potential for a strong winter storm to move across the northern Plain states and/or northern Minnesota by Christmas Day or Boxing Day. It's much too early to say if this storm will impact southern Manitoba and how badly, but there's growing consensus that a major storm system will be tracking across the northern Plains sometime over the Christmas/Boxing Day period. At this point, all we can say is to keep an eye on this potential winter storm that could be impacting holiday travel in southern MB (especially RRV and SE MB) depending on how it tracks. Realize however that models will be jumping around on the possible solutions on this storm system over the next few days until they get a clearer picture of where this storm will track. Stay tuned..
Great article Rob.
ReplyDeleteNow that we are having these almost daily 5 cm dustings and another Potential 20-40cm for xmas and Boxing Day, would you please give us snow updates and accumulative numbers or the url link where these are posted.
Interesting from both a monthly record point of view and spring potential.
Jim.. So far, I've measured 41.4 cm of snow this month, and if we get another 10 or more with that storm on Christmas/Boxing Day, this will be Winnipeg's 2nd snowiest Dec on record, behind only Dec 1909 at a phenomenal 101.3 cm, our snowiest month ever. This could end up as one of our snowiest months in years depending on how much we get on the 25-26th.
DeleteAs for a link on Winnipeg records, I recommend consulting JJC's excellent site at
http://wxrecordbooks.weebly.com/winnipeg.html
Pretty much the "go to" site for Winnipeg weather stats. He does an excellent job compiling and updating stats with the latest numbers.
Very unrepresentative temperatures at the airport this afternoon with fresh snow-cover and light NW flow. Cold drainage/ inversion has temps down to -7 C at YWG. Meanwhile spots that have anything to provide a bit of low level turbulence or lower albedo (fence-lines, trees, shrubs) are much warmer. Downtown thru the south end has temperatures at the freezing mark with melting noted.
ReplyDeleteIf the northwest trend continues on GFS.. we may have start entertaining a scenario with rain for the Christmas/ Boxing day system! Here's hoping..
Looking at the top 24 h temperature rises.. they cluster in occurrence from either winter or mid to late spring (late April to early May). This represents two very different processes - the switch from an arctic regime to a Pacific flow for the winter cases - and perhaps - rapid recovery from a late season snow storm or snow cover in the late spring cases (with a high sun angle and advection of tropical airmasses causing rapid melting). Would be interesting to cross reference the spring cases with any occurrence of snowfall/ snow-cover.
ReplyDeleteAll the April and May cases listed were during very brief (1 or 2 days) influxes of very warm and dry air masses, similar to what we witnessed on May 5th this year (our 35.2°C day). I'd say these situations are the result of much drier air masses as compared to the summer and fall (lack of evapotranspiration), resulting in chilly mornings but very rapid heating in the morning. The April 1985 case did have an 8 cm snowfall a few days earlier but that snow had melted before the heating event.
DeleteInteresting.. in that case, antecedent soil moisture anomalies are likely also telling (dry topsoils allowing for good surface heating and positive sensible heat flux).
DeleteStill looks like a good bet that southern MB will be impacted by that Colorado low Dec 25-26th, although models still not in agreement about how far north storm will go, and how bad Winnipeg will get it. However, even if Winnipeg isn't in the heaviest snow band (greater chance south and east of city), it will still be a disruptive storm for travel, especially through the RRV, SE MB, NW Ontario, and ND/nrn MN. Blizzard conditions with road closures quite possible over the RRV into ND and SE MB, so folks will have to keep an eye on this if they have travel plans over the holidays, especially south and east of Winnipeg.
ReplyDeleteLooking more and more likely that Winnipeg will be getting clobbered by this upcoming storm.. especially Sunday night into early Monday when we get the bulk of the snow (25-30 cm possible) along with strongest winds. Blizzard conditions pretty much a given during that time given the snowfall intensity and winds. Heavy drifting will compound problems with drifts of 60 cm or more likely. Needless to say, travel will be severely impacted with many road closures Sun night into Boxing Day. Get ready folks, looks like another nasty winter storm on the way! Big cleanup Monday!
DeleteI got the snowmobiles gassed up and ready to go; Thanks for the update Rob! Merry Christmas!
ReplyDeleteRob, I've heard that another lengthy cold snap is on the way starting around new year's eve.
ReplyDeleteWhat are your thoughts on this?
Thanks.
Comment yesterday that a weather buoy near the north pole measured temp 30c above normal ( Near melting)
ReplyDeleteIf that was a Buoy was it floating and do we have water at the north pole this year.
What about Santas Sled and the reindeer....Do they Float/ Swim?
All the best at christmas Rob closing in on 15 years
I'll have limited time for updates due to the holidays.. but I'll try to post when possible. Until then.. thanks everyone for comments and all the best this holiday season!
ReplyDeleteThe record single-day snowfall for Christmas Day in Winnipeg is less than 10 cm. Depending on how early Winnipeg begins seeing significant snowfall, this record could be beaten.
ReplyDeleteExtensive freezing drizzle locally - associated with lighter forcing on the periphery of the system in the United States. Strong warm advection and 60-70 kt LLJ causing northwards surge of moderate to heavy band of precipitation in North Dakota. Rain/snow line right now appears to be somewhere between Grand Forks (-4 C and freezing rain reported) and Devils Lake.
ReplyDeleteWill have to watch if above freezing layer (AFL) can sneak into southern RRV and SE Manitoba with this surge of warm advection. If so, snow accumulation will initially be reduced due to mixing with ice pellets and freezing rain.. otherwise as stronger lift/forcing arrives from the south, precipitation locally will switch from freezing drizzle to moderate/heavy snow. Models show AFL eroding as system evolves and deformation zone sets up overnite into Monday - likely producing a switch over to snow for all areas.
Do not recall a major storm as accurately predicted 7 days in advance as this one Rob. Kudos to the People Systems and Training improvements we have seen in the last few years. Awesome
ReplyDeleteThanks for the kind comments Don. Yes, it was a well forecast storm.. and a critical one in terms of timing for the Christmas holidays. High impact, high visibility type of event that would have been a disaster with thousands of stranded people if it was not forecast well. Kudos to met community and amazing weather models that can give plenty of notice for these type of high impact storms.
DeleteDo we have data for accumulations yet? Be interested to see how much snow dropped.
ReplyDeleteBack in Winnipeg after a nice week of sun and surf in Hawaii (Maui) Came back today to a driveway socked in with snow.. still 23 cm deep (on average) 3 days after the big Boxing Day storm. I'm going to estimate 25 cm storm total at my location.. which seems like a reasonable number given other reports from the storm. Thank goodness for my snowblower.. could hardy get into my bay! Welcome back to reality!
ReplyDeleteAnother 1.6 cm of snow today, quite underwhelming given we were expecting between 5-10 cm here in Winnipeg. Nonetheless, that boosts our total December snowfall to 68.6 cm, which makes this the snowiest month in Winnipeg since Nov 1958. It also ranks as Winnipeg's 7th snowiest month ever (since 1872), and 2nd snowiest December on record (only Dec 1909 at 101 cm was snowier.. our snowiest month on record) We've had 2 major snowstorms this month, each with 25+ cm, which is a rarity in Winnipeg. Looking at the snowbanks and the city snow-clearing tab, one can see the impacts of such heavy snowfall in a short period of time. Hopefully we don't get much more snow the rest of the winter, because if we do.. could be a big problem with spring flooding. Let's hope it doesn't come to that..
ReplyDeleteBy the way, this is why taking manual snowfall observations (with a good old fashioned ruler) is so important. According to the automated weather station at YWG airport, we've had only 17.6 mm of melted precip this month. Absolutely NO indication that this has been our snowiest month in almost 60 years! Automated weather stations do a good job recording most weather variables.. but they are terrible at measuring snowfall! This is why it's so important to maintain manual snowfall observations, especially in our major cities where snowfall can have a big impact on municipal budgets.
Can only say with certainty that Nov 1958 and Jan 1916 had two 25+ cm snowfalls. Dec 1909 and Feb 1881 might have, but can't say for sure because it's hard to see if there were seperate events without hourly obs. Regardless, this shows how rare it is to get two or more 25+cm snowfalls in a given month here. This was only the 5th occurrence.
DeleteFrom the end of October 1955 we seemed to get a new 12 inches of snow near the weekends til the middle of the month. By that time Eatons which had a brand new fleet of delivery vans had to swithch back to horses as their vans were no match and stuck all over winnipeg. Outside ofmarch 1966 it is one of rhe few days some parts of the city cancelled school. In those days no one was driven to schoôl but the piles of snow were awesome by midmonth.
ReplyDelete