What is made here
Wine colours
The only colour the rules allow.
Where it is
Porto in Portugal
- Latitude
- 40.9°–41.6° N
- Vineyard altitude
- 117 m to 619 m
- Production zone
- 269,167 ha
Covers the same area as
Douro
Worked out from the boundaries (smallest container first). They follow whole communes, so a neighbour sharing a commune can show up here too.
Boundary drawn from whole communes, so it is a little larger than the legal zone. Boundary: Eurac Research PDO inventory (CC0). Country outlines: Natural Earth. Dots on the zone map are the vineyard points used for climate.
01 · What the law says
The rules
Limits on grapes, yields, ripeness and ageing that every wine labelled Porto must meet.
Other varieties allowed
Besides the main grapes, the rules allow these varieties in some wines. Grape names link where a profile exists.
108 varieties · 4 wines
Alfrocheiro, Alicante Bouschet, Alvarelhão, Alvarelhão Ceitão, Aramon, Arinto, Avesso, Baga, Barreto, Bastardo, Batoca, Bical, Branco Especial, Branco Gouvães, Branco Guimarães, Caramela, Carignan, Carrega Branco, Carrega Tinto, Casculho, Castelã, Castelão, Cercial, Chasselas, Cidadelhe, Concieira, Cornifesto, Côdega do Larinho, Diagalves, Donzelinho Branco, Donzelinho Tinto, Engomada, Espadeiro, Estreito Macio, Fernão Pires, Folgasão, Folha de Figueira, Gonçalo Pires, Gouveio, Gouveio Estimado, Gouveio Real, Grand Noir, Grangeal, Jaen, Jampal, Lourela, Malandra, Malvasia Fina, Malvasia Parda, Malvasia Preta, Malvasia Rei, Marufo, Melra, Mondet, Moreto, Moscadet, Moscatel Galego Branco, Mourisco, Mourisco Branco, Mourisco de Semente, Mourisco de Trevões, Nevoeira, Patorra, Petit Bouschet, Português Azul, Praça, Preto Martinho, Pé Comprido, Rabigato, Rabigato Moreno, Rabo de Ovelha, Ratinho, Roseira, Rufete, Samarrinho, Santareno, Sarigo, Semillon, Sercial, Sevilhão, Síria, Tamarez, Tempranillo, Tinta Aguiar, Tinta Barocca, Tinta Caiada, Tinta Carvalha, Tinta Fontes, Tinta Francisca, Tinta Martins, Tinta Mesquita, Tinta Penajoia, Tinta Pereira, Tinta Pomar, Tinta Tabuaço, Tinto Cao, Tinto Sem Nome, Touriga Franca, Touriga Fêmea, Touriga Nacional, Trincadeira, Valdosa, Varejoa, Verdelho, Verdial Branco, Vinhão, Viosinho, Vital
In the vineyard and cellar: rules for every wine
4,000
Vines per hectare, minimum
Training
Systems allowed
vara (cane); vara e talão (cane and spur); cordão (cordon)
Cellar
Where the wine must be made
Within the production zone
02 · Climate fingerprint
The climate
The growing season averages 18.4 °C, warm on Gregory Jones's scale, with 1,793 growing degree days (Winkler III).
The average year 1991–2020, vineyards at about 399 m
Monthly mean, °CRain, mmGrowing season
- Growing-season temperature
- 18.4 °C
- Warm · 17–19 °C (Jones)
- Growing degree days
- 1,793
- Region III: 1,667–1,943 degree days
- Growing-season rain
- 345 mm
- Of 740 mm a year
- Harvest rain
- 147 mm
- September–October
Copernicus ERA5-Land monthly averages at 5 vineyard points (Vineyard point 1, 476 m; Vineyard point 2, 543 m; Vineyard point 3, 310 m; Vineyard point 4, 272 m; Vineyard point 5, 392 m), moved to each point's height from the model's terrain. Indices that need daily data are not captured yet. How the climate figures are made.
Lower confidence:Monthly reanalysis in complex terrain (height corrections up to 2.6 °C); absolute values may be several degrees out, year-to-year changes are more reliable.
Closest climates in the database
Picked by the data, not by hand: the profiles nearest on season warmth (counted twice), degree days, rain, ripening-month nights and day–night range. Neighbours within 30 km are left out, as they share the same weather.
1. MurfatlarVery similarCompared with Porto: same season warmth, similar rain.
2. Sierra de SalamancaVery similarCompared with Porto: same season warmth, similar rain.
3. Costers del SegreVery similarCompared with Porto: same season warmth, similar rain.
Growing-season temperature
Growing degree days
Growing-season rain
03 · Year by year
35 vintages
Each column is one growing season: heat above or below the 1991–2020 average, and rain at harvest. Pick a year for the details.
Warmer than averageCooler than averageHarvest rain (Sep–Oct)Average harvest rain, 147 mm
2025
- Growing-season temp.
- Growing degree days
- Harvest rain
- Growing-season rain
- September nights
- Hot days and frosts
Seasons are labelled by harvest year (April–October). Year-to-year changes from ERA5-Land; tested against station records in Alto Adige (r = 0.94 for season temperature at Bolzano). Rain varies more locally, so treat single-season rain with some caution. Vintage ratings, harvest dates and frost or hail events have places in the data model but are not loaded yet.
04 · Where the numbers come from
Sources
- A geospatial inventory of regulatory information for wine protected designations of origin in Europe · Candiago et al., Scientific Data 9, 394 (2022); Eurac Research · CC0
- ERA5-Land monthly averaged data (reanalysis-era5-land-monthly-means) · Copernicus Climate Change Service (C3S), Climate Data Store · CC BY 4.0 (Copernicus licence)
- OpenStreetMap vineyard areas (landuse=vineyard), from Geofabrik country extracts · OpenStreetMap contributors · ODbL 1.0
- Copernicus DEM GLO-90 (AWS open data tiles) · European Space Agency / Copernicus · Copernicus DEM licence
- Product specification: Porto (Porto.pdf) · National authority, as filed in the EU register (eAmbrosia) · Official document
- Appellation nesting worked out from boundaries (pipeline/build_nesting.py) · Vinous, from the Eurac PDO boundaries · CC0 (source data)
- Climate profiles calculated by Vinous: method
Still to check (3)
- Generated from EU reference data: check against the current product specification.
- From the specification: Fortified wine (vinho generoso) of 19-22 % vol actual alcohol (light dry white Port from 16.5 %); the 11 % vol natural minimum is an average for the musts. Fermentation is stopped with wine spirit leaving at least 17.5 g/l sugar; sweetness terms range from Extra-Seco (17.5-40 g/l) to Muito doce/Lágrima (over 130 g/l). Partial concentration of Douro musts is allowed. Ageing minima and the special categories (Reserva, LBV, Vintage, Colheita, aged tawnies) are set in Regulamento 242/2010, not reproduced in the text. Grapes must come from vineyard parcels classified under Portaria 413/2001; ageing and bottling may also take place in the Vila Nova de Gaia entreposto. Density may fall to 3,000 vines/ha on terraces (20 % tolerance); vineyards planted before 11 August 1998 are exempt. The rosé acidity minimum is not stated.
- National tier (DOC/DOCG) not captured yet; rules extracted from the specification text.