You will rarely see a rainbow at noon because the sun is usually too high in the sky.

The formation of a rainbow is governed by the laws of refraction and reflection, specifically involving the 'rainbow angle' of approximately 42 degrees. When sunlight enters a water droplet, it slows down and bends, reflects off the back of the droplet, and bends again as it exits. This process disperses the light into its constituent colors, but the light only reaches the observer's eye if the geometry is precise.For an observer on the ground to see the arc, the sun must be at an elevation of less than 42 degrees above the horizon. If the sun is higher than this threshold, the center of the rainbow's circle falls too far below the horizon for the arc to be visible. This is why midday rainbows are virtually impossible in tropical and temperate regions during the summer months when the sun reaches high solar altitudes.According to meteorological optics studies by researchers like Raymond L. Lee Jr., the visibility of a rainbow is also dependent on the antisolar point. This is the imaginary point exactly opposite the sun from the observer's perspective. As the sun rises higher, the antisolar point sinks lower, dragging the rainbow with it until it is completely obscured by the earth.Interestingly, this limitation does not apply if you are at a high altitude, such as in an airplane or on a mountain peak. From these vantage points, it is possible to see a full 360-degree circle of a rainbow even when the sun is high. In winter at high latitudes, the sun may never rise above 42 degrees, making noon rainbows a rare but possible occurrence during those months.