"Sure as a winter's day in springtime" [closed]

What is the meaning of "Sure as a winter's day in springtime". Here is an example of usage: "Sure as a winter's day in springtime, Little Charlotte, I'm going to win that competition for you."

Solution 1:

It is tempting to take the quotation literally. I give you the example of eastern Scotland:

Average April daily high and low temperatures are 10ºC and 2ºC

Average January daily high and low temperatures are 5ºC and -1ºC

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This means that in April there is a good chance that the average daily low temperature will be as low or lower than some of the days in January. Hence, we may be reasonably sure that spring will contain days typical of cold winter days, despite the naïve idea that spring is warmer than winter.

Similarly, despite the apparent unlikeliness of the speaker winning the competition, it is reasonably certain that they will.