Between three and six months a baby still loses heat a little faster than you, so the app dresses a touch warmer than for an older baby outside and at home. Swaddling stops now: the sack takes over for sleep.
Outside: 26°C and up: short-sleeve bodysuit and sun hat. 25°C: short-sleeve bodysuit, pants and sun hat. 24°C: short-sleeve bodysuit, pants, socks and sun hat. 21–23°C: short-sleeve bodysuit, pants and socks. 20°C: long-sleeve bodysuit, pants and socks. 16–19°C: long-sleeve bodysuit, pants, socks and light sweater. 15°C: long-sleeve bodysuit, pants, socks, light sweater and warm hat. 14°C: long-sleeve bodysuit, pants, socks, warm sweater and warm hat. 13°C: long-sleeve bodysuit, warm pants, socks, warm sweater and warm hat. 11–12°C: long-sleeve bodysuit, warm pants, warm socks, warm sweater and warm hat. 7–10°C: long-sleeve bodysuit, warm pants, warm socks, warm sweater, jacket and warm hat. 3–6°C: long-sleeve bodysuit, warm pants, warm socks, warm sweater, jacket, warm hat and mittens. 2°C: long-sleeve bodysuit, warm pants, warm socks, warm sweater, winter jacket, warm hat and mittens. Under 2°C: long-sleeve bodysuit, warm pants, warm socks, warm sweater, winter jacket, warm hat and warm mittens.
At home: 25°C and up: short-sleeve bodysuit. 22–24°C: short-sleeve bodysuit and socks. 19–21°C: long-sleeve bodysuit, pants and socks. 16–18°C: long-sleeve bodysuit, pants, socks and light sweater. Under 16°C: long-sleeve bodysuit, warm pants, warm socks and warm sweater.
For sleep: 26°C and up: short-sleeve bodysuit. 24–25°C: short-sleeve bodysuit (0.5 TOG). 21–23°C: short-sleeve bodysuit (1.0 TOG). 18–20°C: long-sleeve bodysuit (2.5 TOG). Under 18°C: long-sleeve bodysuit and sleepsuit (2.5 TOG).
Between three and six months they still lose heat a little faster than you, so a touch warmer.
Outside and at home, a touch warmer than for a baby of six months, easing off as the months go by.
For sleep, the same TOG as at any age. Once rolling starts, the swaddle stops and the sleep sack takes its place.
Under six months, keep your baby out of direct sun: shade, and a wide-brim hat.
No hats or loose blankets for sleep. Check the neck — warm but not sweaty means just right.