Sea state forecast up to 3 days, by day
Kept by incident.ipma@web-summit.dinis, 11 November 2026, 11:50 UTC
Kept by incident.ipma@web-summit.dinis, 11 November 2026, 11:50 UTC
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IPMA's name for it: Previsão do Estado do Mar até 3 dias, informação agregada por dia. Documented at api.ipma.pt. Drawn at sea.
| Address | https://api.ipma.pt/open-data/forecast/oceanography/daily/hp-daily-sea-forecast-day{idDay}.json |
| Format | JSON |
| Shape | {owner, country, forecastDate, dataUpdate, data: [one object per coastal place]} |
{idDay} | 0 today, 1 tomorrow, 2 the day after: 0, 1, 2 |
| IPMA says it updates | taxa de atualização horária |
| IPMA's file dated (its Last-Modified header) | 2026-11-11 11:31 UTC |
| We last read it | 2026-11-11 11:49 UTC, 3 files, 9824 bytes |
| IPMA's note | "Apenas estão disponíveis dados diários." |
| Field | Type | Unit | Meaning (our English) | IPMA's wording | Where the documentation differs |
|---|---|---|---|---|---|
globalIdLocal | integer | · | the coastal place: an id from sea-locations.json (a node: sea-place) | · | · |
totalSeaMin | number | m | daily minimum of significant wave height | "mínimo diário da altura significativa das ondas, em metros" | · |
totalSeaMax | number | m | daily maximum of significant wave height | · | · |
waveHighMin | string | m | daily minimum of swell height | "mínimo diário da altura da ondulação (swell) em metros" | · |
waveHighMax | string | m | daily maximum of swell height | · | · |
wavePeriodMin | string | s | daily minimum of the swell's peak period | · | · |
wavePeriodMax | string | s | daily maximum of the swell's peak period | · | · |
predWaveDir | string | · | prevailing wave direction (N, NE, E, SE, S, SW, W, NW) | · | · |
sstMin | string | °C | daily minimum of sea surface temperature | · | · |
sstMax | string | °C | daily maximum of sea surface temperature | · | · |
latitude | string (decimal degrees) | ° | latitude of the place | · | · |
longitude | string (decimal degrees) | ° | longitude of the place | · | · |
| File | Answer | Bytes | sha256 | IPMA's file dated (UTC) | We read it (UTC) |
|---|---|---|---|---|---|
| forecast/oceanography/daily/hp-daily-sea-forecast-day0.json | 200 | 3277 | 5ab2e07e8a6324ec… | 2026-11-11 11:31 | 2026-11-11 11:49 |
| forecast/oceanography/daily/hp-daily-sea-forecast-day1.json | 200 | 3274 | 28e7ac461c1d4098… | 2026-11-11 11:31 | 2026-11-11 11:49 |
| forecast/oceanography/daily/hp-daily-sea-forecast-day2.json | 200 | 3273 | 65f3f0cfdde61778… | 2026-11-11 11:31 | 2026-11-11 11:49 |
The links go to IPMA's live files. Full hashes: latest.json. What changed between reads: changes/sea-forecast.json. Our small files made from it: data/sea.json.