Figure 1 (left): Mean temperature and anomaly from normal (C) showing core of exceptional warmth this November over upper midwest
Figure 2: (right) Winnipeg mean daily temperature past 30 days (Oct 16 - Nov 15) showing persistence of above normal temperatures over past 4 weeks
As mild as it's been, it may be surprising to learn that Winnipeg has had even milder starts to November in previous years. At 3.3C, the first half of November this year will rank only as the 8th mildest start to November since 1872. The warmest start to November (as defined by the mean daily temperature from Nov 1-15) was in 1981 and 1931, with an average temperature of +4.9C over the first half of the month. Nov 1981 saw 10 days reach +10C or more in the first half with a peak of 18.2C on Nov 4th. This year, Winnipeg has recorded only 4 days in November of +10C or more. This shows that our warmth this year has been mainly due to exceptionally mild nights, rather than mild days. Frequent cloud cover and lack of cold air intrusions has resulted in a persistence of mild nights with temperatures well above normal minimums for November. The top 10 warmest first halfs of November in Winnipeg since 1872 are:
So what does the rest of November look like? Well, mild weather is expected to continue the first half of this week, then a pattern change around mid week as a strong storm system brings a substantial cool down later this week with temperatures likely falling below normal for the first time this month. We may even see our first shot of accumulating snowfall here in the city Wednesday night into Thursday. Colder than normal temperatures will dominate through next weekend before a moderating trend next week.
|Multi-model ensemble shows big temperature dip coming to |
Winnipeg by Thu Nov 19th (850 mb temps top)
The transition to colder weather will likely be accompanied by
our first snowfall Wed night into Thursday (precip amts bottom)