Today — sit it out — wave, wind and surge pounding.
Sources & confidence
Compiled by the spearo sea-state engine · How it works →
The verdict comes from seven water factors and hard safety gates — not ten tabs. Go or stay.
Our own model
Our own forecast engine — not a third-party widget. It weighs these water factors into one go-or-stay verdict for this coast; the 0–10 dial is that verdict, read out as a number.
Safety gates
It all folds into a single 0–10 score and one verdict: go or stay.
A forecast, not a guarantee — the sea has the last word.
Where to get in, where to hunt
Wind, wave and the swell windows — when to go and the best hours.
The day is picked above, in the hero. Here are that day's windows, the hour-by-hour map and the trends. Tap a window to break down the conditions.
Leave your email — and the moment a window opens at Portland, we'll send the go / no-go verdict. Email is all we need.
What's missing? Tell us what you'd like to see — new spots, species, data or features. We read everything.
Visibility and what drives it — post-storm clearing, river plume, temperature and the thermocline.
spearo.app folds wind, wave, swell period, visibility, tides, water temperature and risk into a single verdict — go to the spot or not. It computes 7 days ahead from open marine models (Open-Meteo, IPMA), with no sign-up and no accounts. Built for solo spearfishing off the rocks, where any mistake costs dearly.
Now live: 3016 spots across 406 stretches of coast — mainland Portugal, Madeira and the Azores.
See all spotsRelief and bottom type, tides, and the depths of each spot.
The models set the window. Whether you go in is read only at the water: count the sets, watch the surge on the entry. If in doubt, you don't get in.
Scouted entries, coloured by today. The colour is the sea state at the spot, not a guarantee: the wash and a slippery entry you judge on site.
Open the seafloor mapBay where the harbour breakwater meets the island, normally dived from a boat as a gentle drift to about 20 m. It lies inside the port boundary, so keep clear of port traffic and follow harbour rules.
Google MapsGo down the ramp at Chiswell and walk in off the steep pebble beach. Pebbles give way at 6–8 m to sand and boulders with weed, sponges and soft corals, reaching about 15–18 m. Swell causes heavy surge and a strong undertow on the exit, and a current can run along the beach.
Google MapsA steep path of about 180 steps leads down to a sheltered pebble cove used for snorkelling and diving. Water is about 3 m just off the beach and reaches 5 m roughly 100 m out. Currents can be strong further from shore.
Google MapsPark at the south end of the Chesil Beach Centre car park and walk in, following the pebble terraces down to a Second World War landing craft at 12–14 m. A current can run along the shore, and old fishing line is common on the wreck, so carry a cutting tool.
Google MapsEnter from the rocks just north of Pulpit Rock and explore the cracks around it, with depths beyond 30 m. Slack water lasts only about 45 minutes, about 4 hours after high water at Portland. The Portland Race is extremely dangerous, so stay close to the rock and have shore cover.
Google MapsFrom the Chesil Beach Centre, walk over the shingle and fin about 90 m out on a compass bearing to the scattered remains at about 12 m. Dive at slack water, about 2 hours after high water at Portland. Swell makes the steep shingle exit dangerous, with a strong undertow.
Google MapsSOLO is the biggest risk: underwater you can black out from lack of oxygen silently and fatally, with no one around. Solo is never truly «safe». Below are the best weather windows; carry a buoy, tell someone your plan and exit time, and any doubt — don't go.
Cameras, map and reference — to hand as you come up.
Recreational spearfishing in the sea is legal in the UK without a licence — breath-hold only is the norm. Never spear salmon, sea trout or eels (Salmon and Freshwater Fisheries Act 1975). Bass: catch-and-release only 1 Feb–31 Mar (rod and line), then 3 a day, 42 cm min. Check the local IFCA/Marine Scotland/DAERA rules — in Cornwall no spearfishing dusk to dawn or with scuba. No-take zones (Lundy, Lamlash Bay, Flamborough) are closed.
Portland has rock entry points such as Church Ope Cove, Pulpit Rock (Portland Bill) and Chesil Cove. The Isle of Portland — boulder ledges on every side, so there is always a lee. Below you'll find each spot (access, shelter and hazards) and today's forecast.
May–October; south-westerly gales in winter; the water clears after calm spells and easterlies.
9–10 °C in March, 16–18 °C in August — 7 mm in winter, 5 mm in summer.
Limestone ledges, reefs and wrecks; strong tidal streams at Portland Bill, heavy boat traffic off Plymouth and Weymouth. No licence; bass rules and IFCA byelaws apply.
Portland: Recreational spearfishing in the sea is legal in the UK without a licence — breath-hold only is the norm. Never spear salmon, sea trout or eels (Salmon and Freshwater Fisheries Act 1975). Bass: catch-and-release only 1 Feb–31 Mar (rod and line), then 3 a day, 42 cm min. Check the local IFCA/Marine Scotland/DAERA rules — in Cornwall no spearfishing dusk to dawn or with scuba. No-take zones (Lundy, Lamlash Bay, Flamborough) are closed.
