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Let 4Shor read the forecast for you.
Every term here is baked into one 0–100 score for your sport and ability, at every location, updated hourly.
GLOSSARY
The forecast,in plain English.
Swell, period, tide state, wave shape — the terms that decide whether it's worth going, and what each one actually means.
- Swell
- Organised wave energy travelling across the sea, generated by wind elsewhere. Long-travelled swell (groundswell) is cleaner and more powerful than locally generated windswell.
- Swell height
- The size of incoming wave energy, usually in metres or feet. On its own it tells you little — height combined with period is what decides how a wave actually breaks.
- Swell period
- The time in seconds between successive waves. Longer period (14s+) carries far more energy, so a "1.5m at 16s" swell breaks much bigger and harder than the height alone suggests. The most under-rated number on a forecast. How to read a surf forecast.
- Swell direction
- The compass direction the swell is travelling from. It determines whether wave energy can reach a given beach or is blocked by a headland or island.
- Groundswell
- Long-period swell that has travelled a long distance from a distant storm. Clean, powerful and well-organised — the surf most riders chase.
- Windswell
- Short-period waves generated by local wind close to shore. Weaker, choppier and closer together than groundswell; fine for learning, underwhelming for experienced surfers.
- Offshore wind
- Wind blowing from the land out to sea. It holds waves up and grooms their faces clean — the classic "glassy" dawn-patrol condition.
- Onshore wind
- Wind blowing from the sea onto the land. It flattens and crumbles waves into mush; a strong onshore can ruin an otherwise good swell.
- Cross-shore wind
- Wind blowing roughly parallel to the beach. Workable for most sports, especially when light.
- Cross-onshore wind
- Wind angled across and slightly onto the beach — the practical sweet spot for kitesurfing and wing foiling, because it lets you ride back to your launch. Reading the wind for kite & wing.
- Gust factor
- The ratio between peak gust strength and average wind speed. A high gust factor means unstable, squally wind that is harder and less safe to ride, even if the average looks ideal.
- Knot
- A unit of wind (and boat) speed equal to one nautical mile per hour — about 1.15 mph or 1.85 km/h. Wind sports are almost always discussed in knots.
- Tide state
- Where the tide is in its cycle — low, mid or high, and whether it is pushing (rising) or dropping (falling). Many spots only work on a particular part of the tide.
- Spring & neap tides
- Springs are the largest tidal range (around new and full moon); neaps are the smallest. Bigger ranges mean stronger tidal flow and faster-changing conditions.
- Fetch
- The distance of open water over which the wind blows to build waves. Longer fetch produces bigger, better-organised swell.
- Bathymetry
- The shape of the seabed. Because the seabed transforms swell as it approaches shore, accurate bathymetry is what lets a forecast predict the wave that actually breaks at a specific spot. How ShorSense™ works.
- Refraction & shoaling
- How waves bend (refraction) and grow (shoaling) as they move into shallower water. These seabed effects are why a 4ft offshore swell can break at 6ft on a sandbar — and why two nearby beaches can be completely different.
- Shore-normal
- The direction pointing straight out to sea, perpendicular to the beach. Wind and swell directions are judged relative to shore-normal to work out whether they are offshore, onshore or cross-shore.
- Significant wave height
- A standard forecast measure: the average height of the highest one-third of waves. It matches what an experienced observer would call "the wave height," which is why forecasts use it.
- Wave condition descriptors
- Categorical labels for wave shape from 4Shor’s nearshore model: peeling (breaks progressively along the face — ideal), hollow (steep, barrelling — expert), crumbly (soft and gentle — beginner-friendly), and flat (no rideable wave).
- ShorSense™
- 4Shor’s proprietary scoring engine. It blends satellite-derived bathymetry, open-ocean wave spectra, nearshore wave modelling, wind and tide into a single 0–100 suitability score for each sport at each ability level, refreshed hourly. How ShorSense™ works.
- Ability tiers
- Beginner, intermediate, advanced and expert. 4Shor scores the same conditions differently for each, because a beginner and an expert want different things from the same day — the same beach can score 78 for a beginner and 34 for an expert.
- Suitability score
- The headline 0–100 number on every 4Shor location. 90–100 Epic!, 80–89 Excellent, 65–79 Good, 45–64 Okay, 25–44 Poor, 0–24 Don’t Bother — for your chosen sport and ability, right now.