Tuesday 3 December 2013

Pleasant Start to November But a Cold And Record Breaking Second Half

E=estimated due to imprecise data
     November actually started very pleasant with well above normal temperatures in the first half with only brief cool downs. This was in sharp contrast to parts of Alberta and Saskatchewan which already had snow on the ground by Halloween. 2 days reached 10°C, on the 2nd and 13th.

     Things made a drastic turn mid-month as arctic air plunged southern Manitoba into winter. A few unexpectedly high snowfalls each dumped 5-10 cm on Winnipeg.

    However, the biggest story of the month was the cold and high pressure on November 22 and 23 as a very unusually strong arctic high pressure system invaded the Prairies. Temperatures plunged into the -20's at night, over 15 degrees below normal. Winnipeg's low of -26.8°C on Nov 23 was the coldest temperature in November since 1996 when we reached -27.9°C on Nov 26. Even some -30°C readings were seen in western Manitoba and in Saskatchewan, including Roblin (-30.7°C) and Shoal Lake (-31.0°C), Manitoba, and Regina Saskatchewan (-31°C).

     However, even more impressive, 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 on November 23 (or station-level pressure of 101.64 kPa). The previous record high station level pressure in November was 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

12 comments:

  1. Thanks to all those who voted in the snowfall poll, here's the results so far:

    4 votes for 10-20 cm
    1 vote 2-5 cm
    1 vote trace-2 cm

    Average vote: 10-11 cm

    ReplyDelete
  2. Looks like we'll get a decent snowfall after all in the RRV and southeastern Manitoba, including perhaps Winnipeg. I'm calling for 10-20 cm in Winnipeg spread out over a full 2 days (includes what we're getting today already). Snow will likely continue through to Thursday before tapering off.

    ReplyDelete
  3. yeah, E.C. has put out a Special Weather Statement indicating that as well.

    ReplyDelete
  4. Lots planned for December this year:

    Fall stats will come tomorrow
    Manitoba 2013 t-storm season stats come next week
    Canada 2013 severe t-storm season stats to come the week after
    Top 10 events of 2013 series starts December 29 or 30 (opinion poll associated with this will come a week before Christmas) (wont make it as long as last year; I didn't have any readers when I did it last year so I had not bothered keeping it short back then)

    ReplyDelete
  5. With a heavier band of snow setting up right over Winnipeg this evening, looks like snowfall totals tonight may be higher than the 1-3 cm I planned to get by morning. This snow is essentially just a bonus for now, the real system really doesn't come until tomorrow.

    ReplyDelete
  6. Yeah, seems likr that band of snow is virtually stationary over us. Hmmm. Could we receive 5+CM unexpectedly just tonight tonight ahead of the real deal tomorrow.....certainly possible.

    ReplyDelete
    Replies
    1. Would not surprise me! Already picked up 2 cm here. For once the heavier bands actually stay over Winnipeg.

      Delete
    2. Sorry, that 2 cm is on top of the 1 cm from this afternoon.

      Delete
  7. Seeing what happened last night, I'm raising my forecast to 15-30 cm. Turning out to be a decent storm, maybe not the massive blizzard some had hoped for, but better than nothing.

    ReplyDelete
  8. Yeah, I agree with you JJ. I'm up to 10 CM already since last night here in Windsor Park. Certainly not a massive blizzard but a pretty decent storm nonetheless. Things will get even nastier once winds pick up this afternoon.

    ReplyDelete
  9. A tough measure today at my place with that northeasterly wind making my home act like a bit of a snow shadow whilst at the same time getting some blowing off the roof with the strongest gusts. Nonetheless, measured just under 9 cm so far along with just under 6 mm of water equivalent. Anybody with measurements, especially water equivalent measurements, feel free to share them. I'm not too sure about the accuracy of my water equivalent measurements today so it would be nice to compare.

    ReplyDelete