Icy · 5–10 °C
Thurne
River · 3 measured points · latest reading 3 h ago. Real sensors in the water, not a forecast.
Measured now9.4 °CMartham
Rule of thumb (experienced)9 minBeginners stay well shorter and get out before the shivering starts.
Cold shock1–2 minClassic winter swimming. Strong cold shock, calm the breathing first.
Cold bandIcyThe classic. Calm breathing first, then swim.
Trend since September
The water is cooling by 1.0 °C per week.
When does it become ice swimming here?
Below 10 °C: winter swimming is on right now. Below 5 °C (ice swimming proper) expected from 25 November.
Linear extension of the measured trend, not a forecast – one cold front or mild spell shifts everything by weeks.
Measuring points
9.4 °C
Martham3 h ago
Icy9.8 °C
Repps Bank3 h ago
Icy11.3 °C
Womack3 h ago
ColdNearby
New Year
67
67 days until 1 January. New Year's Day dips with measured temperature follow in December.
Cold scale
0–5 °CPolar
5–10 °CIcy
10–15 °CCold
15–20 °CFresh
over 20 °CSummer
Five bands every winter swimmer knows. The “one minute per degree” rule is for experienced swimmers, beginners stay well shorter.
The app for it
Your water on your phone, with an alert below your limit
BrrChecker shows 13,000+ measured spots with history and neighbours, alerts you when your water drops below your own threshold, and keeps your winter swimming diary with BrrLog: temperature, time in the water, streak.