Thursday, May 31, 2018

City swamped with heavy rainfall - up to 75 mm reported in River Heights

A slow moving band of showers and embedded thunderstorms moved across the city of Winnipeg late Wednesday afternoon, resulting in a deluge of rain over much of the city. The heaviest rain moved in from the southwest around 4 pm, and proceeded to slowly track across the downtown core over the next 2-3 hours. By the time the rain tapered off in the early evening, amounts of 25 to 75 mm were reported across the city, the heaviest in the Tuxedo-River Heights area.  The heavy rain caused flash flooding of Winnipeg streets, with Pembina Highway temporarily closed due to flooding under the Jubilee overpass. By contrast, very little rain fell over southeast sections of the city with 5 mm or less over south St Vital into the Sage Creek area.

Rainfall map for city of Winnipeg based on unofficial Weather Underground
reporting sites up to 7:15 pm May 30 2018. Values in inches, contours in mm 

Official rainfall amounts for the event included:

Winnipeg Forks:  46.1 mm
Winnipeg airport: 26.3 mm 

Unofficial amounts included:

River Heights: 74 mm
Tuxedo: 69 mm
U of Winnipeg: 52 mm
Linden Woods: 25-40 mm
Charleswood: 28 mm (my site)
Whyte Ridge: 27 mm

The rainfall has made up for a very dry start to spring with virtually no rain through April into the first half of May.  As of today, May precipitation now sits at 54 mm for Winnipeg airport and 70 mm at the Forks. Average monthly precipitation in Winnipeg for May is around 60 mm.

Rainfall map from Weatherlogics using over 300 rainfall reports

Wednesday, May 09, 2018

Very dry weather continues.. Winnipeg closing in on top 5 dry spells of all time

The dry weather of the past 2 months continues into May, with no measurable precipitation recorded so far in the month. In fact, as of May 9th, Winnipeg has gone 27 consecutive days without any measurable precipitation. The last day with measurable precipitation in Winnipeg was on April 12th when 1.2 mm of melted snow was recorded at the airport. (measurable precipitation is defined as a day with 0.2 mm or more of melted precipitation (rain or snow)  With no significant precipitation expected through May 15th, this current dry spell may enter the record books as one of the top 5 longest dry spells in Winnipeg since records began in 1872. The chart above shows the top 5 longest dry spells in the city, the longest being 47 days without measurable precipitation in the fall of 1976. The longest dry spell in the spring (which is a more serious time for dry weather) was in 1980 when Winnipeg went 40 straight days without measurable precipitation.  How long this current dry spell will last is difficult to say at this point.. but increasingly it looks like it may become historic before it's finally over. The dry weather has caused major headaches for city firefighters who have had to battle numerous grass fires in the past few days in and around the city.     

UPDATE:  Well, the dry spell ended at YWG airport but there's a bit of a controversy over exactly when the streak ended.  Officially, the first measurable precip at YWG airport in May was on May 17th when 0.8 mm of rain fell. That would have put the dry spell at 34 days, tied with 1882 as the 4th longest dry spell on record.   However, it appears the official precipitation gauge at the airport (XWG CS station) was possibly under-reporting rainfall from the 15th through the 19th. A co-located rain gauge at XWG picked up 0.2 mm of rain on the 15th, as did many private stations in Winnipeg with some light rainshowers that day. If that's the case, the dry spell would have ended on the 15th for a streak of 32 days, which would be the 6th longest dry spell on record. Which is correct? I'm going with the latter (32 day streak) with 0.2 mm of rain on the 15th, not much, but just enough to break the precip-free streak.     

Thursday, April 19, 2018

Well, it took awhile, but it looks like spring has finally sprung in Winnipeg and southern MB as sunny skies and temperatures in the mid teens signalled the warmest weather here since last October (6 months ago!)   And the springlike weather is expected to continue this weekend with temperatures in the upper teens, possibly closing in on 20C in some localities!  The only fly in the ointment will be gusty southerly winds accompanying the warm temperatures over the weekend, especially Sunday with southerly winds gusting to 50-60 km/h. Otherwise, it'll be a great weekend to enjoy the outdoors like riding your bike, getting some swings in at the driving range, or starting on that spring cleaning! Temperatures are expected to cool off to around 7-10C Tuesday, but then should rebound into the upper teens to 20C by next Thursday again. So spring is here.. at least for the next little while! Enjoy! 

Sunday, April 01, 2018

Cold start to April.. spring slow to arrive this year

Those hoping for a quick transition to spring as the calendar switches to April are going to be disappointed as the Prairies remain stuck in a below normal temperature pattern for at least the next 1-2 weeks.  The colder than normal pattern will mean that an extensive lingering snowpack over the Prairies and northern Plains will be slow to disappear, making it even harder for warmer temperatures to surface. As a result, expect a slow and gradual melt this year.. likely leading to the latest snowmelt here since 2014. Precipitation over southern MB looks below normal as well as the main storm track sets up south of the international border, for this week anyways. Models are hinting of a more active pattern setting up next week over the southern Prairies which may bring some accumulating snow into southern MB again by early next week (ugh!)  

As of April 1st, the highest temperature in Winnipeg so far this year has been only +5.4C (March 27th) with no hint of double digits temperatures in the near future.  In comparison, Winnipeg had already reached double digits twice in March of 2017 (including 12.3C on March 29th), and another 10 times in the first 2 weeks of April 2017 (19.8C on Apr 8th). We'll need to lose a lot more snowpack before we see temperatures like that this year.  Note that normal highs in early April in Winnipeg are +5C, rising to +10C by mid month and 15C by April 30th.   

Thursday, March 01, 2018

Potent storm system to bring widespread snow to southern MB Sunday night into Tuesday

Surface weather map valid midnight Sunday night shows
system bringing widespread snow across southern MB
A potent storm system is forecast to develop over the central US plains later this weekend, and is expected to bring widespread snow to southern MB Sunday night into Tuesday. After a quiet winter that has seen very little snowfall (the lowest Dec-Feb snowfall in at least 30 years in Winnipeg), this upcoming storm system has the potential to produce the most significant snowfall of the season for much of southern MB, including Winnipeg. There's still a lot of uncertainty with how this storm will track and develop, but at this point, it's looking like a widespread snowfall of 15-30 cm is possible for many areas by Tuesday.

Preceding this main storm will be an initial system on Saturday that will bring a band of snow which will push across southern MB and settle into the Interlake region. This initial impulse may bring a couple cm of slushy snow to southern MB, but it shouldn't have much impact with temperatures around the melting point. Some rain may even mix in Saturday afternoon.

Things will start to get interesting by Sunday afternoon as the main storm system starts intensifying as it moves out of Colorado. This storm will track into Minnesota by Sunday night spreading a widespread area of snow across southern MB. The snow may be wet and slushy at first with temperatures hovering around the freezing mark Sunday through Sunday night. Snow could be heavy at times Sunday night into Monday as the storm system slowly pushes across Minnesota, with gusty northeast winds as well. This will make for treacherous driving conditions across southern MB Monday. Snowfall will linger into Tuesday before the system gradually winds down. As noted, snowfall amounts are still tough to predict this far out based on uncertainty in storm track and temperature profile, but in general, it looks like most of southern MB could be looking at 15-30 cm between Saturday and Tuesday night. The highest amounts would likely be over the western Red River valley with some upslope enhancement along the Pembina escarpment, but many areas have the potential to see significant snowfall with embedded bands of heavier snow. Stay tuned as more information becomes available on this developing storm system.     

Sunday, February 11, 2018

Brief mid week warm up.. but generally below normal this week and next. Snow drought continues..

It's been a cold start to February across southern Manitoba, and it looks like the cold weather will persist through much of this week and next. There will be some brief warmups from time to time (such as this Wednesday), but overall, it looks like a below normal temperature pattern is expected across the Prairies through next week. As of Feb 10th, the average temperature at YWG airport has been -21.4C, about 6C below average for the first 10 days of the month.  It's been the 3rd coldest start to February in the past 20 years (only Feb 2007 and 2014 had colder starts) 

As for this week, it will be another cold start to the work week as temperatures drop to the -30C mark early Monday with winds of 10-15 km/h producing windchills near -40.  Highs of -16C are expected by afternoon, about 6C below the average high of -10C for this time of year. Temperatures will moderate to -5C by Tuesday but gusty SW winds of 30-50 km/h will make it feel colder. On Wednesday, a clipper system will track through the MB interlake area bringing a brief warmup to southern MB, with highs rising close to the freezing mark in Winnipeg by Wednesday afternoon. The mild spell will be short lived however as a trailing cold front pushes through in the afternoon, sending temperatures falling as strong northerly winds develop. Some snow and blowing snow will likely develop as well Wednesday afternoon and evening as the colder air spreads in. This will lead into another few days of colder than normal weather to end the week Thursday and Friday. Temperatures are expected to moderate again next weekend, but again, the warmup looks short lived as colder weather returns for the third week of February. 

Precipitation-wise, new snowfall looks minimal again across southern MB. There may be a bit of snow with the Arctic front Wednesday (tr - 2 cm) but other than that, no significant precipitation is expected over southern MB through next weekend. As of Feb 10th, Winnipeg has seen only 52.8 cm of snow this winter.. its lowest snowfall to this point in the winter since the winter of 2011-12 (48 cm to Feb 10th) and the 2nd least snowfall to Feb 10th in at least 20 years. (On average, Winnipeg gets about 76 cm of snow by Feb 10th). Last winter, Winnipeg had seen 121 cm of snow by Feb 10th - over twice the amount this season - thanks in large part to the snowiest December in 58 years.  The meager snowfall this winter has boosted the city of Winnipeg's 2017 municipal budget surplus by another $6 million thanks to less than projected snowclearing operations.

Monday, January 29, 2018

Get ready for a wintery blast Tuesday! Strong winds and snow with blowing snow and poor visibilities on the way for Winnipeg and RRV

Intense clipper system will be tracking across central MB
Tuesday bring snow, strong winds to much of the province.
Winds/blowing snow will be the main issue for RRV
An intense clipper system will be tracking across Manitoba Tuesday bringing strong winds and snow to much of the province. Here in Winnipeg and the Red River valley, winds will be the main story rather than snowfall Tuesday, especially through the midday and afternoon hours when southerly winds will be howling up the valley gusting to 70 or even 80 km/h. These winds, combined with loose and falling snow, will lead to widespread blowing and drifting snow with poor to blizzard-like conditions in the open country. Keep this in mind if you plan on being on the roads tomorrow. Snowfall amounts with this system will be highest over the Interlake and central MB, where 10-20 cm of snow is possible.. while amounts here in Winnipeg and the RRV will be in the 5 cm range. Snowfall amounts however will be impossible to measure accurately as winds will be so strong here in the RRV, with extensive drifting. Winds shift into the NW behind the system by Tuesday evening, with gusts of 60-70 kmh at times bringing colder temperatures for the rest of the week. 

Monday, January 08, 2018

One more mild day Tuesday, then colder weather pushes in Wednesday with gusty winds and some snow

Weather map for noon Wednesday shows southern  MB
in cold northerly flow behind an Arctic cold front 
Above normal temperatures will continue across southern Manitoba Tuesday as a southeast flow sends temperatures up to the freezing mark by Tuesday afternoon across the RRV including Winnipeg. The mild weather will persist Tuesday night into early Wednesday before a sharp Arctic cold front pushes through the RRV Wednesday morning, shifting winds into the north and sending temperatures falling through the day. In addition, the cold front will be accompanied by a band of snow as it pushes through, with 1-3 cm possible through midday. The gusty north winds will also lead to blowing and drifting snow especially outside the city, with a period of poor visibilities likely as the band of snow pushes through. Driving conditions will likely become poor for a few hours Wednesday across the RRV so be prepared for a return to wintery conditions if you're out and about. Temperatures near -5C early Wednesday in Winnipeg will plummet to -12C by noon, and -18C by 5 pm, so be prepared for a much colder commute home.  Cold but dry weather is expected for the remainder of the week into the weekend. 

Tuesday, January 02, 2018

Coldest final week of December in over 80 years. Frigid weather eases as we head into January

It was a frigid end to December over much of the continent, including throughout the Prairies and southern Manitoba. In Winnipeg, the final week of the month averaged a bone-chilling -27.7C, the coldest final week of December since 1933, and the 4th coldest since records began in 1872. 

The frigid finish to December was in stark contrast to the first 3 weeks of the month which were milder than normal. In fact, through Dec 23rd, December was averaging about 3C above normal (-10C vs -13C)  But that all changed by Christmas Eve as frigid temperatures moved in for the holidays with temperatures averaging over 10C below normal between Christmas and New Year's Eve. As a result, December ended up about 1.5C below normal in Winnipeg with a mean temperature of -14.8C  (vs the December "normal" of -13.2C)  

December 2017 in Winnipeg. Very cold finish
spoiled an otherwise mild month  
Luckily, the massive Arctic airmass that has plagued much of North America over the past week has retreated for the beginning of January with temperatures rising to normal values in southern MB, and even above freezing in Alberta, which had seen temperatures of -40C just a couple days ago. Colder weather will prevail through this week (but not like last week), before another moderating trend sets in next weekend with temperatures near or above normal over southern Manitoba. Seasonably cold weather is expected next week.  Mid January marks the coldest time of the year on average in southern MB with normal highs of -13C and lows of -23C for Winnipeg. Daily averages slowly climb through the latter half of January rising 2C by Feb 1st.