Rain makes the same temperature feel colder, and wet layers stop keeping anyone warm. The app dresses for how the day feels, and below 20°C in rain it adds a jacket to keep the layers underneath dry, even where it isn't needed for warmth.
What the app suggests in the rain, from the skin out, for a baby of 6–12 months:
25°C: short-sleeve bodysuit, pants and sun hat. Warm — light single layers. 24°C: short-sleeve bodysuit, pants, socks and sun hat. Warm — light single layers. 21–23°C: short-sleeve bodysuit, pants and socks. Warm — light single layers. 20°C: long-sleeve bodysuit, pants, socks and jacket. Mild — add a light mid layer. A rain shell keeps the layers dry. 16–19°C: long-sleeve bodysuit, pants, socks, light sweater and jacket. Mild — add a light mid layer. A rain shell keeps the layers dry. 15°C: long-sleeve bodysuit, pants, socks, light sweater, jacket and warm hat. Mild — add a light mid layer. A rain shell keeps the layers dry. 14°C: long-sleeve bodysuit, pants, socks, warm sweater, jacket and warm hat. Cool — a mid layer plus a hat. A rain shell keeps the layers dry. 13°C: long-sleeve bodysuit, warm pants, socks, warm sweater, jacket and warm hat. Cool — a mid layer plus a hat. A rain shell keeps the layers dry. 7–12°C: long-sleeve bodysuit, warm pants, warm socks, warm sweater, jacket and warm hat. Cool — a mid layer plus a hat. A rain shell keeps the layers dry. 3–6°C: long-sleeve bodysuit, warm pants, warm socks, warm sweater, jacket, warm hat and mittens. Cold — full outer layer and a hat. 2°C: long-sleeve bodysuit, warm pants, warm socks, warm sweater, winter jacket, warm hat and mittens. Freezing — everything on, cover the hands. −5 – 1°C: long-sleeve bodysuit, warm pants, warm socks, warm sweater, winter jacket, warm hat and warm mittens. Freezing — everything on, cover the hands.
The jacket is there for the wet as much as for the cold: in rain the app adds it on days that would need no jacket if they were dry.
Indoors, or in a warm car, bus or train, take the hat and outer layers off.
0–3 months, 12°C: long-sleeve bodysuit, warm pants, warm socks, warm sweater, jacket and warm hat. 3–6 months, 12°C: long-sleeve bodysuit, warm pants, warm socks, warm sweater, jacket and warm hat. 6–12 months, 12°C: long-sleeve bodysuit, warm pants, warm socks, warm sweater, jacket and warm hat. 1–3 years, 12°C: long-sleeve bodysuit, warm pants, socks, warm sweater, jacket and warm hat.
Indoors, or in a warm car, bus or train, take the hat and outer layers off.
Check the neck — warm but not sweaty means just right.