30:T497,md`# How comfortable is outside? 👉🏽 [Jump to viz](https://observablehq.com/@drio/is_it_nice_out_there#cell-658) I saw [this site](https://mydewpoint.com/#)(often down☝🏻) from [Stefan](https://twitter.com/stefanbfritz) that visualizes the current weather in your area using the dew point. I find it a very effective way to determine how comfortable you will be outside (why are we not using the dew point instead of temperature and humidity to talk about the weather?). I wanted to reproduce it in this notebook. ### Dew Point The dew point is the *temperature* at which the the air has to be cooled to achieve a relative humidity of 100%. What? It is a metric to measure how much moisture is in the air. If we have 100% relative humidity, the air cannot hold more moisture/water. If the dew point is high, the air is holding a lot of water. The higher the dew point, the most uncomfortable is goint to be. Here are two examples: - City A: Temperature *80F* and dew point: *50F*. - City B: *72F* and dew point: *68F*. Would you be more comfortable outside in city A or city B? In A. We have a higher temperature but there is less moisture in the air. `31:T9bc,style = html`