Tuesday 31 December 2013

#7, #6 and #5 - Top 10 Weather Stories of 2013 in The Winnipeg Area

#7 - The 4 major snowstorms & blizzards of early 2013


     The first 3 months of 2013 featured 4 major snowstorms and blizzards. Coincidentally, all but one occurred on a Monday!

     A Colorado Low January 11-12 brought the first blizzard in the RRV since March 2011. Winds of 50-60 km/h and gusts over 70 km/h combined with abundant fresh snow. 10-15 cm fell in Winnipeg while 15-25 cm fell to the southeast, including about 20 cm in Steinbach. Roadways were extremely trecherous, visibilities were near-zero for several hours and snow drifts approached a metre deep in some areas. Visibility at Winnipeg airport was 1 km or less for 27 consecutive hours.

By @annhoogie;Wpg Beach Feb 18
     A vigorous Alberta Clipper brought another blizzard to the RRV February 17-18. The storm began as freezing rain and ice pellets in the afternoon of Feb 17, covering highways southeast of Winnipeg in ice. Blizzard conditions by evening lasted until the following afternoon. Conditions were worst south of Winnipeg where winds of 60-70 km/h gusted up to 80 km/h. Whiteout conditions prompted the closure of highways 1, 16, 59 and 75. In total, 4-7 cm of new snow fell in Winnipeg while 10-15 cm fell to the south and east. The storm caused power outages in Windsor Park, St. James and in the town of Île-des-Chênes. In addition, a 54-year old man passed away west of Landmark after leaving his vehicle stranded in the ditch during the blizzard.

     Another vigorous Alberta Clipper moved in March 4. Heavy snow bands hovered south and southwest of Winnipeg for hours dumping 30-60 cm of snow. Upsloping along the escarpment due to strong east winds enhanced totals. Some totals included 56 cm in Miami, 35 cm in Morris, 20-30 cm in Brandon and 12-19 cm in Winnipeg (click here for a totals map). 5 cm fell in 1 hour in Winnipeg, highlighting the snow's intensity. The storm was blamed for knocking out power to about 5,500 residents in Linden Woods.

     A Montana Low March 17-18 gave the RRV its third blizzard of the winter. The worst conditions were south of Winnipeg where winds of 50-60 km/h gusted to 70 km/h. Generally, 10-17 cm of snow fell across southern Manitoba. Whiteout conditions prompted the closure of highway 75, as well as Fermor Avenue east of Lagimodière Boulevard in Winnipeg. Visibility was so bad that snow plow operations were halted in the Morris area. After the storm, snow depth sat around 50-80 cm across southern Manitoba. A depth of 58 cm in Winnipeg was the deepest in March since 1966.


#6 - A week of drenching thunderstorms


     The June 20 to 26 period was the highlight of flash flooding this year in southern Manitoba.

Storm south of Wpg before it entered the city
     On June 20, a quasi-stationary t-storm cell over southwest Winnipeg dumped 50-75 mm of rain over a very isolated portion of the city in about 2 hours. Rainfall amounts dropped off very quickly as you moved away from the storm. A few kilometres away only a few millimetres fell, including a measly 8.5 mm in south St Vital and 1 mm in northeast Winnipeg. This steep gradient looks impressive on the City of Winnipeg's rainfall map seen here. Flash flooding made some roads almost impassable and many properties experienced flooding, including the newly built Ikea which was evacuated. A Weather Moment blog has a great summary of the event.

     Two rounds of widespread thunderstorms early June 22 and 23 in southwestern Manitoba dumped biblical rainfall. In total, both events dumped 80-150 mm of rain from Melita to Brandon to Dauphin, creating severe overland flooding. The town of Reston was hit hard with over 140 mm of rain. Floodwaters were so deep that part of the town had to be evacuated. Winnipegosis and Pipestone were also hard hit. In Brandon, 90-120 mm of rain caused street and basement flooding.

    Also on June 22, a line of very slow moving storm cells northwest and southwest of Portage la Prairie in the afternoon and evening dumped unimaginable rainfall. Radar estimates pointed to 150 + mm of rain in just a few hours northwest of Portage.

     Lastly, severe thunderstorms June 25 dumped more heavy rains in southwestern Manitoba. Unfortunately, Reston was once again hit hard, receiving 104 mm of rain! Storms in the area then merged into a squall line which raced through the RRV at night. Frequent lightning, strong winds and torrential rains occurred. As much as 30 mm fell in southern parts of Winnipeg. A home was struck by lightning in northeast Winnipeg, igniting a fire, but no one was injured. In addition, winds up to 100 km/h caused power outages in southwestern Manitoba.

Radar imagery from the NWS of the squall line as it began racing across southern Manitoba

#5 - January in November


     Winter began with a fury this year with frequent blasts of unseasonably cold air in late November. The cold conditions were especially prevelent in the last 10 days of the month when temperatures dropped well into the minus teens and twenties at night. At times daytime highs were in the minus teens, some 10 degrees below normal.

     Most impressive was on November 23 as a very strong arctic high pressure system moved into southern Manitoba. With a morning low of -26.8°C at Winnipeg airport, it was the coldest November night since November 26, 1996 when we dipped to -27.9°C. Temperatures were much colder out west, dipping to the -30's in Saskatchewan and parts of western Manitoba.

     However, the biggest story was the high pressure. Winnipeg reached its highest pressure reading ever recorded in November since these records began in 1953. Standardized sea-level pressure topped out at 104.86 kPa (or station-level pressure of 101.64 kPa). This beat the previous station level pressure record of 101.53 kPa on November 20, 1978.

Top 7 highest station-level pressure readings in November in Winnipeg since 1953
Rank
Date
Max station-level pressure
1
Nov 23, 2013
101.64 kPa
2
Nov 20, 1978
101.53 kPa
3
Nov 19, 1978
101.50 kPa
4
Nov 22, 2013
101.48 kPa
5
Nov 20, 2008
101.45 kPa
6
Nov 29, 1964
101.33 kPa
7
Nov 13, 1996
101.30 kPa

4 comments:

  1. No record broken in Winnipeg this morning with a low of -37.9°C, just shy of the old record of -38.3°C in 1884. However, this is the coldest December temperature since 1933 when we reached -41.1°C on December 28. Here's a list of lows across southern Manitoba this morning:

    Wasagaming -41.2°C (old record -47.8°C in 1967)
    Roblin -40.8°C (old record -43.0°C in 1992)
    Shoal Lake -39.3°C (old record -34.3°C in 2012... however only has data since 1995)
    Carberry -39.0°C (old record -40.6°C in 1967)
    Brandon -38.7°C (old record -41.1°C in 1946)
    Pinawa -37.6°C (old record -40.0°C in 1984)
    Sprague -36.3°C (old record -43.9°C in 1946)
    Pilot Mound -35.1°C (old record -37.8°C in 1967)

    Of this list, only Shoal Lake broke a record, but it is of note that that town only has data back to 1995.

    It's also very cold in northern Ontario. Thunder Bay broke an all-time December low wind chill record this morning with a wind chill of -51. Old record was -49.7 on Dec 31, 1967. The city also dropped to -39.6°C this morning, easily breaking the old record of -33.3°C in 1946 and 1967.

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    Replies
    1. That low of -39.6°C in Thunder Bay is also very close to an all-time record. Coldest temperature ever recorded there was -41.1°C on January 30, 1951. Records go back to 1941.
      However, it is the coldest temperature ever in December with the old record being -37.8°C on December 13, 1976.

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  2. Thanks to everyone who voted in the top weather stories poll! Poll will close this weekend as I wrap up the top 10 series. Also, if you have any comments or suggestions, please feel free to share them!

    ReplyDelete
  3. Attention is now turning to another Alberta Clipper expected for Friday. Models have been ramping up snowfall predictions in the last few runs. 5-10 cm possible. Blowing snow looks to be a concern.

    Another reinforced push of arctic air will move in behind the low.

    ReplyDelete