Guide
Thickness, zips and sizing, in plain English.
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The Cornish water report
Typical sea temperatures on St Ives Bay and the suit we reach for. Every body runs a little warmer or colder, so treat it as a starting point.
Jan to Mar
9°C
Sea temperature
5/4 hooded, boots and gloves
Apr to Jun
12°C
Sea temperature
4/3 with boots
Jul to Sep
16°C
Sea temperature
3/2, or a 2mm shorty in August
Oct to Dec
13°C
Sea temperature
4/3 and boots, hood by December
| Thickness | Water | Months | Our suit |
|---|---|---|---|
| 5/4 hooded | 8 to 12°C | Dec to Apr | Tidewalker |
| 4/3 | 11 to 15°C | Oct to Nov, Apr to Jun | Longshore |
| 3/2 | 14 to 18°C | Jun to Sep | Shoreline |
| 2mm shorty | 17°C and up | Jul to Aug | Rockpool |
A chest zip keeps more water out, so it is warmer on a cold dawn. It is a little fiddlier to get into, but the suit moves with you and lasts.
A back zip is the easiest to get in and out of, which suits kids and anyone changing in a car park. It lets in a little more water.
Snug everywhere, with no gaps at the lower back or under the arms. Between sizes? Go by chest.
| Size | Height cm | Chest cm | Waist cm | Weight kg |
|---|---|---|---|---|
| S | 168 to 174 | 92 to 97 | 76 to 81 | 60 to 68 |
| M | 174 to 180 | 97 to 102 | 81 to 86 | 68 to 76 |
| MT | 180 to 186 | 97 to 102 | 81 to 86 | 72 to 80 |
| L | 178 to 184 | 102 to 107 | 86 to 91 | 76 to 85 |
| XL | 182 to 188 | 107 to 113 | 91 to 97 | 85 to 95 |
| Size | Height cm | Bust cm | Waist cm | Hips cm |
|---|---|---|---|---|
| 6 | 155 to 161 | 78 to 82 | 60 to 64 | 84 to 88 |
| 8 | 158 to 164 | 82 to 86 | 64 to 68 | 88 to 92 |
| 10 | 161 to 167 | 86 to 90 | 68 to 72 | 92 to 96 |
| 12 | 164 to 170 | 90 to 95 | 72 to 77 | 96 to 101 |
| 14 | 167 to 173 | 95 to 100 | 77 to 82 | 101 to 106 |
| Size | Height cm |
|---|---|
| Age 6 | 115 to 125 |
| Age 8 | 125 to 135 |
| Age 10 | 135 to 145 |
| Age 12 | 145 to 155 |
| Age 14 | 155 to 163 |
Measure around the widest part of your chest, under the arms and level with the tape.
Measure around the narrowest part of your waist, keeping the tape level.
Measure your height without shoes, against a wall.
Measure around the widest part of your chest, under the arms and level with the tape.
Measure around the narrowest part of your waist, keeping the tape level.
Measure your height without shoes, against a wall.
Add boots when the water drops below 13°C, and gloves and a hood below 10°C. They make the difference between a short session and a long one.
