#10, #9 & #8 - Top 10 Weather Stories of 2015 in the Winnipeg Area

#10 - Warm and ''Dusty'' April

Fire along I-29 in ND. Credit: The Grand Forks Herald

An early spring, a dry winter and warm windy conditions in April all combined to produce blowing dust and help fuel brush fires in April. The worst conditions were seen on April 15 when record high temperatures in the mid twenties combined with dry topsoil and wind gusts over 80 km/h to produce widespread blowing dust in the Red River Valley. In addition, visibility and breathing conditions were worsened by brush fires. In Winnipeg, temperatures reached 24.8°C at the airport, breaking the old record of 24.1°C in 2006. Winds were sustained between 50 and 60 km/h and gusted up to 80 km/h. Burning permits were cancelled as a result of the dry and windy conditions. The winds were strong enough to rip shingles, knock over light posts, cause power outages and throw debris which broke windows, as reported on social media. Brush fires were numerous, but some of the worst were southwest of Steinbach and just south of the border along I-29. In fact, I-29 was closed from the border all the way to Grand Forks due to smoke and blowing dust. This was just a couple days after another brush fire destroyed a home and killed one person in the rural municipality of Rhineland on April 13.

Another burst of warmth occurred at the end of April with highs in the high twenties. A high of 27.4°C on April 30 was the warmest in April since 2001. In the end, April averaged 5.4°C, tied 36th warmest since 1872. Daytime highs were the most anomalous, averaging 13.2°C, 2.3°C above normal and tied 20th warmest. 6 days exceeded 20°C, the most since 2010 and above the normal of 4 days. The first 20°C of the year occurred on April 11, almost a month earlier than in 2013 and 2014.

#9 - Mild January and a Winter With Little Snow

After a frigid start to 2015, a warm spell blessed southern Manitoba with above normal temperatures in the second half of January. A 17-day streak of above normal temperatures occurred from January 14 to 30. During this period, daily highs averaged -1.9°C and daily lows average -12.1°C. These were about 10°C warmer than normal for the period. At the Winnipeg International Airport, 6 days exceeded the freezing mark and 6 days never saw temperatures dip below -10°C. The warmest days were January 22 and 23 when temperatures soared into the mid single digits. The airport reached 3.7°C and 3.1°C respectively, but it was even warmer inside Winnipeg with highs between 4 and 6°C recorded. Some parts of southern Manitoba never even dipped below freezing on January 23. The extended warm spell  melted what little snow was on the ground. In addition, only 5 cm of new snow fell between January 4 and 31. By the end of the month, snow depth in Winnipeg was just 12 cm, the 12th thinnest on record since 1941.

Several days of gloomy skies and freezing drizzle also occurred during the warm spell. 5 days saw liquid precipitation in the form of drizzle, freezing drizzle or light rain. Less than 1 mm of accumulation occurred.

In the end, January averaged -13.7°C, tied with 2010 for 19th warmest since 1873. 

December was also very mild. The December to January period averaged -11.9°C, the 17th warmest on record since 1872. Thanks to a frigid February, the winter as a whole only tied for 33rd warmest and averaged -14.3°C. 43 cm of snow fell from December to February, the 28th least snowy winter. However, only about 31 mm of precipitation fell, making it the 9th driest winter on record since 1872.

#8 - A Very Humid Summer

Despite near normal temperatures, very high humidity occurred in summer 2015. With an average dewpoint of 13.6°C, summer 2015 tied with 1996 for 4th most humid summer on record since 1953. Interestingly, 9 of the last 20 summers were among the top 10 most humid summers. 22 days from June to August saw dewpoints exceed 20°C in Winnipeg this summer, the 2nd most 20°C dewpoint days since 1953. The 1981-2010 normal is just 10 days. 8 daily high and high minimum dewpoint records were broken during the period.

Table: Top 10 most humid summers (Jun-Jul-Aug) since 1953 (by average dewpoint temperature):
1.   14.3°C (2010)
2.   14.1°C (2012)
3.   13.7°C (2005)
4.   13.6°C (1996, 2015)
6.   13.5°C (1955, 1995, 1998)
9.   13.4°C (2001)
10. 13.3°C (1963, 1983, 2003)

July was most humid. With an average dewpoint of 16.1°C, it was the 2nd most humid July and month on record since 1953. The 1981-2010 normal is 14.2°C. The month featured an 8-day streak with dewpoints over 20°C mid month. A maximum dewpoint of 24.1°C was achieved on July 12, breaking the old record of 23.9°C in 1955 for the day. In total, an amazing 14 days saw dewpoints over 20°C, tied with 1957 for the most 20°C dewpoint days in July on record since 1953.

Table: Top 5 most humid Julys since 1953 (according to average hourly dewpoint observation)
1. 16.5°C (2012)
2. 16.1°C (2015)
3. 15.5°C (1966, 1989)
5. 15.4°C (1955, 1983, 2007, 2010)

Table: Top 6 most 20°C dewpoint days in July since 1953
1. 14 days (1957, 2015)
3. 12 days (1955, 2001, 2005)
6. 11 days (1966)

In August, the main story was mid month when a 5-day heat wave hit southern Manitoba. Temperatures soared over 30°C on each of these 5 days and in some cases, over 32°C. The hottest day was August 14 when temperatures soared into the mid thirties. Records were broken, including in Brandon (36.6°C). High humidity accompanied the heat wave with 4 days of dewpoints over 20°C. Dewpoint temperatures peaked at 24.5°C in Winnipeg on August 15, shattering the old record of 21.7°C in 1972 for the day. It was also the latest occurrence of dewpoint over 24°C in a year since 1953. High minimum temperature records were also broken in Winnipeg (21.2°C) and Morden (22.0°C).

Top 10 Weather Events of 2015 Around Winnipeg - Poll

In anticipation of the top 10 weather events series for 2015, I have added a poll below for all of you to participate! What do you think were the top 3 weather events of 2015 around Winnipeg? Thank you for the taking the time to paricipate! In the past, I have used the results to decide the ordering of the events and this year could be the same. Feel free to use the ''other'' option if I missed an event you thought deserved to be on the list.


Next year (2016), I might expand this top 10 weather events series to all of southern Manitoba instead of just Winnipeg. This way, more of the big events (such as the July 27 southwestern Manitoba tornadoes) would be included. I have not decided for sure yet if I will do this. Let me know in the comments if this is something you would prefer as well.

Warm November Closes 4th Warmest Fall Since 1872

Warm fall weather continued into November across southern Manitoba. With an average mean temperature of -0.9°C in Winnipeg, November tied for 16th warmest since 1872. This was 3.7°C above the 1981-2010 normal.

The bulk of the warmth was in the first half of the month. In fact, Winnipeg saw an incredible 25-consecutive days of above normal temperatures from October 26 to November 19. Five days exceeded 10°C in November, slightly above the normal of three days. No record highs were broken however.

November was also unusually moist. Dewpoints averaged -2.9°C in Winnipeg, the highest on record for November since 1953. This beat the previous record of -3.0°C in 1981. The most impressive dewpoints were on November 16 and 17 when dewpoint temperature reached 9.4°C and 9.3°C respectively. These smashed the old daily records and were the latest occurrences of dewpoint over 9°C on record. Thanks to the humidity, a record high minimum temperature of 5.3°C was also achieved on November 16.

There was also a lack of snow. The first accumulative snowfall of the season was on November 18, a month later than the 1981-2010 normal of October 18. This tied with 1880 for 4th latest first snowfall accumulation (0.2 cm +) of the season.

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It was a very warm fall across southern Manitoba. All three months finished in the top 30 warmest on record since 1872. The following table summarizes the average high, mean and low temperatures for each fall month in Winnipeg:

Month	High Temperature	Mean Temperature	Low Temperature
September	22.2°C 9th warmest	15.8°C 6th warmest	9.4°C 4th warmest
October	12.9°C 30th warmest (tie)	7.1°C 30th warmest (tie)	1.3°C 40th warmest (tie)
November	2.8°C 21st warmest (tie)	-0.9°C 16th warmest (tie)	-4.7°C 16th warmest

The fall as a whole finished 4th warmest since 1872, averaging 7.3°C. Brandon also had a 4th warmest fall on record (since 1890), averaging 6.2°C.

Top 10 warmest falls (Sep-Oct-Nov) in Winnipeg since 1872 (by average mean temperature):
1.  8.6°C (1963)
2.  7.9°C (1931)
3.  7.5°C (1923)
4.  7.3°C (1953, 2009, 2015)
7.  7.2°C (1948)
8.  7.1°C (1914, 1920)
10. 7.0°C (1922)

It was a moist fall as well. Dewpoints averaged 3.2°C in Winnipeg, second only to 2009 when dewpoints averaged 3.6°C. September was the 3rd most humid on record and November the most humid on record.

Summer-like September

 With an average temperature of 15.8°C, it was the 6th warmest on record since 1872 in Winnipeg. It was also the warmest since 2009 and the 2nd warmest since 1948.

Top 10 warmest Septembers in Winnipeg since 1872 (by average mean temperature)
1.  17.7°C  (2009)
2.  16.8°C  (1948)
3.  16.6°C  (1940)
4.  16.3°C  (1897)
5.  16.1°C  (1906)
6.  15.8°C  (2015)
7.  15.6°C  (1931, 1967)
9.  15.4°C  (1920, 2013)

The month started with a 3-day heat wave as temperatures soared into the low 30's. High humidity was the main story with humidex values reaching 42.0 on September 3 and 40.1 on September 2. The humidex of 42.0 was the second highest on record for September since 1953. Prior to this year, humidex values above 40 had been achieved only 4 other times in September. Dewpoint temperature peaked at 23.1°C on September 3 as well, the second highest on record for September since 1953.

The early September heat ended with the last widespread thunderstorm events of the year on September 4 and 5. Nocturnal storms early on September 4 dropped nickel to toonie-size hail south and east of Winnipeg and near Strathclair and Shoal Lake in southwestern Manitoba. Drenching thunderstorms moved up the Red River Valley and southeastern Manitoba in the afternoon. Winnipeg was hard hit with 30-50 mm of rain in less than an hour alongside wind gusts over 80 km/h. 41.1 mm of rain fell throughout the day at the airport, breaking the old record of 36.8 mm in 1872 for the day. Additional drenching thunderstorms moved through in the evening the following day. 15-30 mm fell south and east of Winnipeg with close to 40 mm near Letellier.

Warm Thanksgiving Weekend With a Windy Finish

The warmest temperatures of October coincided with the Thanksgiving weekend. Temperatures soared into the 20's on the Saturday and Sunday. Many parts of southern Manitoba broke records, but not Winnipeg. The warmest temperatures were along the US border with highs near 28°C in Pilot Mound, Sprague and Morden. The weekend did not finish perfectly however. A strong long pressure system brought the stormiest day of the month on Thanksgiving Monday with winds the main story. Sustained winds were between 60 and 80 km/h and gusts between 80 and 100 km/h. Damage occurred, especially to trees and power lines. The system brought the seasons final thunderstorms in Winnipeg on Sunday the 11th. This put this year's thunderstorm season at Winnipeg airport at 127 days long (June 7 to Oct 11), tied for 11th shortest season since 1953.