Wednesday, 4 December 2013

A Dry Fall With a Few Impressive Records

     With only half the normal rainfall, Fall 2013 was the least rainiest since 2003 and 20th least rainiest since 1872. However, even more impressive is that only about 55 to 60 mm of precipitation (rain and melted snow) fell, placing Fall 2013 in the top 12 to 17 driest on record and driest since 2001. The reason for the range in precipitation is due to extremely erroneous precipitation measurements in November at the airport which have made it next to impossible for me to come up with an exact amount.

Sep 6 storms southeast of Winnipeg
     The season started anything but Fall-like as we experienced an extension to summer tying for 8th warmest September on record. September 6 was a super-hot day and one of the hottest in September history. This was when the first significant record was broken this Fall. Temperatures soared to nearly 34°C and humidex values reached 40. In Winnipeg, humidex peaked at 40.4, the 4th highest in September and latest occurrence of humidex over 40 since 1953. Decent thunderstorms formed late in the afternoon and evening in southeastern Manitoba.

     October was fairly uneventful for Winnipeg. The highlight was widespread thunderstorms in southwestern Manitoba October 11 which dumped 40-60 mm of rainfall in many areas. Brandon's 43.4 mm for the day was the city's second highest daily rainfall in October since 1890, and was enough to push October 2013 to the 11th rainiest on record.

     Another extreme event occurred in late November. A very strong arctic high pressure system sent pressure readings skyrocketing to record values for November. Winnipeg's station-level pressure topped out at 101.64 kPa on the 23rd, the highest pressure reading recorded in November since these records began in 1953.

Other stats about Fall 2013:
First freeze at Winnipeg airport: September 21 at -1.3°C
Length of growing season at airport: 131 days (4th longest in the last 20 years)
First freeze Winnipeg downtown: October 20 at -1.6°C
Number of severe thunderstorm days in Manitoba: 7 (all in September)
Only 5.0 mm of rain fell in the first 25 days of September in Winnipeg


  1. Hard too say with all the blowing and drifting but my estimate would be at 14 CM at my place in Windsor Park since yesterday. More snow still falling tonight giving another possible 5 CM with blowing drifting causing treacherous conditions.

    Also noticed that Robs Obs although an estimate is at 13 CM, so I'd say generally between 10 and 15 CM has fallen in the city with as mentioned another 5 CM still possible.

    1. Looks like just over 11 cm here in South Vital as of 7:30 pm. And yeah, the drifting snow has been a pain. Unfortunately, my water equivalent measurements are way too high, likely due to snow accumulating in the gauge from the roof. I tried to keep the gauge as far away from the house as possible, but I have a small yard unfortunately.

  2. I'm calling it a total of 14 cm here at my place as of 9:30 am this morning. This is for the whole system since Tuesday afternoon.

    Looks like the winning answer to the poll is 10-20 cm so congrats to the 4 respondents who got that!

  3. JJ, how long do you think this cold snap will last? Could it be one of coldest December's we've seen in years by the the time the month ends?

    Thanks, Anon

    1. It appears the cold will dominate through most of the month, with only brief reprieves here and there associated with clipper systems. A cold December like this is a bit of an anomaly based on the trend of the 21st century which has been for warmer Decembers, so this December will likely be one of the coldest we've seen in a while.

      The most recent cold Decembers we've had were in 2000 and 2008. Actually, December 2000 ended up being the 3rd coldest December on record, while in 2008 it was the 14th coldest. Too early to say how this one will rank this year.

    2. ,
      Thanks for providing not only a great new Website, twitter comments and Blog and Links,

      Your JJ C Winnipeg Weather blog produced some interesting charts which referred to record November Hi Pressure (and the lowest Nov Temp since 1996)readings and listed the other record years Seems like I had a spreadsheet with all the other weather anomalies for those years... Impressive list to say the Least . Put a spring in my step if you catch my  drift. Such warm dry and short winters those were.
      1964-5,1978-9,1996-7, and 2008-9, and the question is 2013-14?? We appear to be off to a great start! Worth watching at least.

    3. Thanks for the nice comments Don and I'm glad you find the statistics I provide interesting! Weather statistics are my specialty!

  4. Took a core sample of the new snow from one of my snow boards. 13 cm melted down to 16.3 mm, so it's clear the wind really compacted the snow. I used my cocorahs gauge to do this.
    The wind really made measurements difficult for this system, but looks like grand totals for Winnipeg are in the 15-20 cm range. I'm raising my initial total of 14 cm to 17 cm.

  5. Just found this site today from Robs blog and its really great! I like your focus on extreme weather events with lots of details that offer a different perspective. I really like all the thunderstorm stats you have on here and the detailed reports on thunderstorm events, something I’m very passionate about. I did a thunderstorm analysis for Winnipeg and came up with a detailed spread sheet of all the recorded years since the observation records began in 1953 with graphs and what not. A lot of my numbers that I came up with are the same as yours for number of thunderstorm days, season period between storms, etc. I wish there was a way to share this spreadsheet with you as you might find it interesting.

    1. Cool, where did you gather the thunderstorm stats (like was it just on from the hourly data on Environment Canada's website)?

      If you like thunderstorm stats, I'll be having a couple thunderstorm season posts up in the next couple weeks giving stats about the 2013 season in southern Manitoba and across Canada.

  6. Absolutely incredible cold for this time of year to our west. Consider ourselves lucky to only be reaching about -30°C or just above -30°C! Some lows approaching and hitting -40°C and wind chills in the -50's in parts of Alberta and Saskatchewan this morning. Will have some official lows this afternoon, but here's some lows so far (unofficial):

    Val Marie, SK -42°C
    Brooks, AB -42°C, wind chill -52
    Sundre, AB -40°C wind chill -49
    Willow Creek, AB -40°C
    Leader, SK -39°C wind chill -52
    Barrhead, AB -39°C
    Kindersley, SK -38°C, windchill -50

    Edmonton Int'l dropped to -39.0°C last night, after a daytime high of -30°C!
    Suddenly our -29°C doesn't seem so bad!