The Month of The Deluge

     Rain will forever be remembered as the top story of June 2014. An active pattern for southern Manitoba in the second half of the month brought multiple weather systems with widespread thunderstorms and heavy rains.

Hailstorm northwest of Wpg June 21

     The first of these active periods was a multi-day rain event June 13-16. 69.9 mm of rain fell at the airport, making it the most significant rain event since the biblical rains of late May 2010. In general, 65 to 80 mm fell on the city. Heaviest rainfall totals were found just north and east of Winnipeg, including 93.5 mm in Beauséjour and 120.6 mm in Lockport. These locally higher totals were thanks to training thunderstorms on June 14. The wettest day of the month was on June 15 as a Colorado Low brought widespread heavy rains to southern Manitoba. With 40.1 mm of rain at the airport, this obliterated the old record high rainfall for the day of 18.3 mm in 1928.

     Yet another multi-day rain event occurred June 27 to July 1. Multiple waves of rain and thunderstorms drenched southern Manitoba, especially the southwest. A general 35 to 65 mm fell over Winnipeg. To our west, it was much, much worse, with 100-200 mm of rain in southwestern Manitoba and southeastern Saskatchewan. The following map shows rainfall totals across southern Manitoba June 27 to 10 am July 1.

    Brandon received 139 mm up to this morning, enough to bring the June total to 251.6 mm. This not only makes June 2014 the rainiest June on record in Brandon, but also the rainiest month ever since records began in 1890. They obliterated the old record rainiest month of 217.3 mm in August 1980. Creeks and rivers are at some of their highest levels ever seen this time of year in the area. Flooded basements and severe overland flooding are also an issue around the city. In Winnipeg, 147.1 mm of rain fell in June, ''only'' the 12th rainiest June on record since 1873. Higher totals fell in other parts of the city, including 170.1 mm here in south St Vital. Even higher amounts fell in more isolated parts around Southdale for instance.

Damaging winds also occurred June 29-30 across southern Mb

     Much of the rainfall in parts of southwestern Manitoba fell as a major low pressure system moved in from south of the border June 29-30. This system intensified rapidly with surface pressure dropping to unusually low levels for this time of year. In Winnipeg, the station-level pressure bottomed out at 95.78 kPa at 6 pm on June 29, the 4th lowest pressure minimum in June since 1953.

Table: Top 4 lowest station-level pressure minimums in June since 1953 in Winnipeg

Rank	Minimum station-level pressure	When?
1	94.86 kPa	June 7-8, 1954
2	95.37 kPa	June 6, 2008
3	95.74 kPa	June 21, 2000
4	95.78 kPa	June 29, 2014

     Other than the rain, temperatures averaged bang on normal with an average mean of 17.0°C.

     For my below normal months streak records, I use the normal of the previous 30 years. As a result, using the 1984-2013 normal June mean of 17.1°C, June averaged 0.1°C below this normal. Therefore, June was the 9th consecutive below normal month. This ties with 1949/1950, 2008/2009 and 2012/2013 for 4th longest below normal streak since 1872.