Category
|
Aug 2017
|
1981-2010 normal
|
Deviation
|
Rank
|
Avg high temp.
|
25.5°C
|
25.3°C
|
+0.2°C
|
59th warmest (tie)
|
Avg mean temp.
|
17.7°C
|
18.7°C
|
-1.0°C
|
51st coldest (tie)
|
Avg low temp.
|
9.9°C
|
12.2°C
|
-2.3°C
|
16th coldest (tie)
|
|
|
|
|
|
Total rainfall
|
13.8 mm
|
79.2 mm
|
-65.4 mm (-83%)
|
7th driest
|
|
|
|
|
|
Avg dewpoint
|
11.4°C
|
12.8°C
|
-1.4°C
|
16th lowest
|
|
|
|
|
|
T-storm days
|
3 days
|
6 days
|
-3 days
|
5th least (tie)
|
|
|
|
|
|
30°C days
|
3 days
|
5 days
|
-2 days
|
51st least (tie)
|
|
|
|
|
|
Avg wind speed
|
11.7 km/h
|
15.4 km/h
|
-3.7 km/h
|
Least windy
|
|
|
|
|
|
- Least windy August on record since the 1920s (see stats and rankings table above). Old record for lowest average hourly sustained wind speed in August was 12.6 km/h in 1972. Also the second least windy month on record since the 1920s.
- Record low dewpoint of 2.1°C on August 24. Old record 2.2°C in 1958. Dewpoint records since 1953.
3 - Discussion:
With an average hourly sustained wind speed of 11.7 km/h, it was the least windy August on record in Winnipeg, beating the old record of 12.6 km/h in 1972. It was also the second least windy month, as seen in the following table:
Rank
|
Average hourly sustained wind
|
Month/year
|
1
|
10.8 km/h
|
Jul 1972
|
2
|
11.7 km/h
|
Aug 2017
|
3
|
12.1 km/h
|
Jul 1985
|
4
|
12.2 km/h
|
Feb 1986
|
5
|
12.5 km/h
|
Dec 1978
|
The dryness was a big story in August. Winnipeg Airport only received about 13.8 mm of rain. Note that this amount is considered an estimate because the morning rains of Aug 9 occurred while the Airport station was offline. Amounts from this timeframe are from The Forks as a result. With only 13.8 mm, it was the 7th driest August since 1873 in Winnipeg. Highest amounts fell in the northeast side of the city with over 50 mm in Garden City as a result of the heavy storm on August 4. Around 25 mm fell in St Vital and Transcona as a result of heavier rains on August 9. The Airport only had 6 days with measurable rainfall (0.2 mm or greater) in August, well below the normal of 11 days. Western sections of the city also went 2 full weeks without measurable rainfall from July 26 to August 8.
The month finished a full degree below normal, which was the result of cool nights. 16 days dipped below 10°C, well above the normal of 9 days and the most since 2007. The monthly minimum of 2.1°C on August 24 was the coldest temperature in August since 2004. Locally temperatures did fall to freezing east of the city and in northern Manitoba. Temperatures even fell below freezing in Hadashvile (-0.1°C) and Thompson (-1.5°C).
August also featured a lack of humidity. The maximum dewpoint was only 17.5°C at the Winnipeg Airport. Normally we would see 3 days with dewpoint over 20°C in August.