Certainly, there are many less subtle examples of the vageries of weather than this; but on my "Yahoo" 'Home' page, today's high temp. in Seaside, OR.. is, 68 degrees fht; tomorrow's projected high: 78 degrees; which goes to show, that our Sun's annual apparent {though not actual}, slow journey southward.. in the fall, is Not always the main temperature determinant, or factor!
 
Then again, as if the weather isn't confusing enough; there's No guarantee, that tomorrow's weather here {or most places}, will be what they forecast.
- For that to be the case, would require an even more enormous amount of {weather} data-input; probably by several-fold, what it is now; and then there's always the 'known unknowns,' as to what importance each of these numerous additional minor factors, {not presently accounted for},
should be given, as to their relative importance?!
 
The 'good' news, is that today's era of weather forecasting, is basically more accurate {day-in, & day-out}, than not!..