This is a less technical answer, by a non-physicist.
The uncertainty principle primarily applies when you examine individual particles. In layman's terms, it says that you can't know both the momentum and position of a particle perfectly accurately: the more accurately you determine one, the less accurate the other is.
However, quantum mechanics allows us to determine probabilities. And when you aggregate enormous numbers of particles, the total measurement comes very close to the expected probabilities. As an analogy, you can't predict whether an individual coin flip will be heads or tails, but if you perform millions of flips, you can be pretty sure that the number of heads will be about half of them.
There isn't anything special about light in your question. I'm also 100% certain about the location and momentum of my chair. Theoretically, the atoms could all suddenly relocate to different places in my room (or anywhere else, for that matter), but the probability is infinitessimal. A few particles might occasionally flit somewhere, but they're negligible when dealing with the chair as a whole.
And the same is true for the light going through your window. Many photons will deviate from the expected path, but when we deal with the enormous number in a ray of sunlight, the average is what we see.