Wind direction

I understand the prevailing winds are west to east, but for the past several weeks and looking ahead up through labor day, the wind has been east to west. Is this common this time of year? I was planning on riding from KC to STL starting Sept 7. But now I am starting to wonder if I should do the opposite direction? Thoughts from those who are Missouri residents?

Two years ago, my wife and I did the Katy in mid-September. The winds were out of the east that week, which I found unusual. I've done the Katy 8 times in June and the winds were almost always from the west. I only remember a few days when the wind made a significant difference.

If you like to start riding shortly after sunrise, there is one big advantage to heading west: the Sun won't be in your eyes.

My wife and I will be leaving St. Charles on September 10th. If you start from KC, you just might see us on a silver tandem.

The question of wind comes up every so often, so I will copy-paste some of what was discussed in the past here. The only thing predictable about the wind is its randomness. The textbooks talk about the "prevailing Westerlies", but those are trade winds. Here in the Midwest, our winds come from every direction, but the most common is out of the South (and bringing up lots of Gulf moisture). Just today alone, the wind shifted from East to Southeast to South and now to West. So you really can't count on a consistent direction. And when the South wind hits the river bluffs that run East-to-West along the Katy (Rocheport and eastward), it splits it. So you can have it in your face and a half mile later, it is at your back. If you are interested in wind directions for your area, look up "wind rose", which is a graph that shows the predominant winds for select cities. Here is one for Jefferson City, about mid-point of the trail (scroll down to the bottom). https://www.meteoblue.com/en/weather/historyclimate/climatemodelled/jefferson-city_united-states-of-america_4392388 As you can see, by far the prominent direction is from the South, followed by the Southeast. Another interesting fact is that the resistance caused by wind is a cube of the speed. So if you are riding into a 5 mph headwind and later it becomes a 10 mph headwind, then you are facing not twice, but 8 times the resistance as you would expect (take the factor and cube it, in this case, 2^3=8). Certainly starting off your day into a strong wind will make for a tiring day. The best way to plan/prepare is to assume that the wind will be your enemy for part of the trip. Also note that the winds in Missouri are much calmer from about June 1 to September 1, as the jet stream moves farther North during the summer.