Pack or skip
Packable down jacket for London in December
Verdict
Pack it
Lows around 37°F — the packable puffer covers 90% of layering needs.
Why
London in December averages highs of 46°F, lows of 37°F, 12 rainy days.
That climate means a packable down jacket earns its space in the bag. Lows around 37°F — the packable puffer covers 90% of layering needs.