Thursday, 24 September 2015

Catching up on Seasonal Summaries - Spring 2015

After two consecutive cold springs, 2015 finally brought some warmer conditions. Spring 2015 averaged 4.5⁰C, tying with three other years for 22nd warmest spring since 1873. This was a nice change after a 16th coldest spring in 2013 and 18th coldest spring in 2014.

Early Spring

Nearly-snowless Winnipeg on March 13
Similarly to 2010 and 2012, spring came very early in southern Manitoba this year. The winter snow pack disappeared already by mid March, allowing for temperatures to reach well into the teens, at least 15 degrees above normal for that time of year. The peak of the warm spell only lasted a couple days on March 14 and 15 but was still pretty impressive. Temperatures were highest along the US border. Morden reached highs of 18.3⁰C and 17.6⁰C, the earliest readings over 16⁰C on record since 1904. The 18.3⁰C high on March 14 also broke the old 2012 record by an impressive 7.1 degrees! Winnipeg also broke a record on March 14 with a high of 13.2⁰C (old 11.4⁰C in 1981). A high of 14.3⁰C the following day was just shy of the old record of 14.4⁰C in 2012. Nights were unusually mild as well. A morning low of 6.7⁰C on March 15 was the warmest morning low for so early in the year since 1953. The last time we had a morning low that warm and that early in the season was on March 19, 2012 with a morning low of 16.0⁰C.

Snow cover in Winnipeg disappeared by March 15, tying with 1995 for 3rd earliest snow melt since 1955. This occurred over a month earlier than in 2013 (April 28) and 2014 (April 21) and was similar to a 2nd earliest snow melt in 2012 (March 14).

In the end, March averaged -3.0⁰C in Winnipeg, the 20th warmest March since 1872.
The first thunderstorms of the season occurred on March 30 with some lightning and pea-sized hail north and south of Winnipeg.

Mild and Dusty April

Blowing dust on Kenaston, Blvd April 15 (by
There were a couple brief but significant cool downs in early and mid April. However, a generally warm pattern continued. The first 20⁰C of the year occurred April 11 with a high of 22.1⁰C, just over a week earlier than normal. 

An early spring combined with limited winter and spring precipitation to create dry soils in April. Dust was blown around on warm and windy days as a result. April 15 was the worst when southerly wind gusts over 80 km/h caused locally reduced visibility in blowing dust. Smoke from brushfires only worsened visibility and breathing conditions. The winds also caused some property damage, such as to windows and shingles, according to social media reports. The strong southerly winds were also transporting some record breaking warmth. Winnipeg’s high of 24.8⁰C broke the old record of 24.1⁰C in 2006.

Another hot spell occurred late April with highs reaching high 20’s. A high of 27.4⁰C April 30th in Winnipeg was the warmest in April since 2001.

Wetter in May

Conditions turned wetter come May across southern Manitoba with above normal rainfall. Winnipeg missed the worst with the bulk of the rain occurring to our south, especially south of the border. In fact, Fargo, ND recorded its wettest May on record with close to 200 mm of rain

May Long Weekend Colorado Low

Snow & uprooted tree in Wpg Beach (by @seanledwich)
One of the most intense low pressure systems in the last decade occurred just in time for the May Long Weekend. Rain, wind and even snow were problems for 2-3 days. Sunday, May 17 was downright miserable with sustained winds of 50-70 km/h, wind gusts up to 90 km/h, temperatures in the low to mid single digits and all-day steady rains. Winnipeg Int’l A recorded 31.3 mm of rain for the day, breaking the old record of 22.9 mm in 1903. The 2-day rain total was generally 35-55 mm in Winnipeg and 50-90 mm along the US border. Overland flooding, especially over farm fields, occurred. The strong and damaging winds also lasted for several hours, causing minor damage and ripping twigs and branches off trees.
Rain changed to snow Sunday night into early Victoria Day morning (May 18). 2.5 cm fell in Charleswood in Winnipeg, the latest occurrence of snow since 2002 when a trace cm fell on May 23. This was also just shy of the old record of 3.0 cm in 1963 for the day. Prior to this year, snow had fallen on May 18 only four times since 1872. Even heavier snowfall fell west and north of the city with 10-15 cm from Boissevain to Lake Manitoba to the western shore of Lake Winnipeg.

The Year up to Now

The year up to May averaged almost bang on normal with an average temperature of -3.9⁰C. Only February finished well below normal at 5.7⁰C below normal. January and March were almost 3⁰C above normal.

1 comment:

  1. Summer summary will be posted soon as well. I will try to post these summaries more on time from now on.

    I hope someday I will be able to get back to normal regular postings and updates on here.